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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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#ifndef DRIZZLED_SESSION_H
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#define DRIZZLED_SESSION_H
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#include <boost/make_shared.hpp>
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#include <boost/thread/condition_variable.hpp>
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#include <boost/thread/mutex.hpp>
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#include <boost/thread/shared_mutex.hpp>
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#include <boost/thread/thread.hpp>
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#include <sys/resource.h>
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#include <drizzled/catalog/instance.h>
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#include <drizzled/catalog/local.h>
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#include <drizzled/copy_info.h>
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#include <drizzled/cursor.h>
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#include <drizzled/diagnostics_area.h>
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#include <drizzled/file_exchange.h>
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#include <drizzled/ha_data.h>
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#include <drizzled/identifier.h>
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#include <drizzled/lex_column.h>
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#include <drizzled/my_hash.h>
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#include <drizzled/named_savepoint.h>
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#include <drizzled/open_tables_state.h>
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#include <drizzled/plugin.h>
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#include <drizzled/plugin/authorization.h>
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#include <drizzled/pthread_globals.h>
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#include <drizzled/query_id.h>
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#include <drizzled/resource_context.h>
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#include <drizzled/session/property_map.h>
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#include <drizzled/session/state.h>
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#include <drizzled/session/table_messages.h>
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#include <drizzled/session/transactions.h>
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#include <drizzled/sql_error.h>
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#include <drizzled/sql_lex.h>
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#include <drizzled/sql_locale.h>
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#include <drizzled/statistics_variables.h>
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#include <drizzled/system_variables.h>
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#include <drizzled/system_variables.h>
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#include <drizzled/table_ident.h>
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#include <drizzled/transaction_context.h>
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#include <drizzled/util/storable.h>
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#include <drizzled/var.h>
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#include <drizzled/visibility.h>
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#define MIN_HANDSHAKE_SIZE 6
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class EventObserverList;
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namespace internal { struct st_my_thread_var; }
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namespace table { class Placeholder; }
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class Internal_error_handler;
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/* Classes in mysql */
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#include <drizzled/global.h>
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#include "rpl_tblmap.h"
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class Query_log_event;
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class Slave_log_event;
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class Lex_input_stream;
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class TableShareInstance;
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enum enum_enable_or_disable { LEAVE_AS_IS, ENABLE, DISABLE };
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enum enum_ha_read_modes { RFIRST, RNEXT, RPREV, RLAST, RKEY, RNEXT_SAME };
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enum enum_duplicates { DUP_ERROR, DUP_REPLACE, DUP_UPDATE };
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enum enum_delay_key_write { DELAY_KEY_WRITE_NONE, DELAY_KEY_WRITE_ON,
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DELAY_KEY_WRITE_ALL };
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enum enum_slave_exec_mode { SLAVE_EXEC_MODE_STRICT,
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SLAVE_EXEC_MODE_IDEMPOTENT,
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SLAVE_EXEC_MODE_LAST_BIT};
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enum enum_mark_columns
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{ MARK_COLUMNS_NONE, MARK_COLUMNS_READ, MARK_COLUMNS_WRITE};
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enum enum_filetype { FILETYPE_CSV, FILETYPE_XML };
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extern char internal_table_name[2];
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extern char empty_c_string[1];
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extern const char **errmesg;
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#define TC_LOG_PAGE_SIZE 8192
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#define TC_LOG_MIN_SIZE (3*TC_LOG_PAGE_SIZE)
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#define TC_HEURISTIC_RECOVER_COMMIT 1
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#define TC_HEURISTIC_RECOVER_ROLLBACK 2
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extern uint32_t tc_heuristic_recover;
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#define Session_SENTRY_MAGIC 0xfeedd1ff
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#define Session_SENTRY_GONE 0xdeadbeef
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extern DRIZZLED_API struct drizzle_system_variables global_system_variables;
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typedef struct st_user_var_events
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user_var_entry *user_var_event;
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uint32_t charset_number;
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} BINLOG_USER_VAR_EVENT;
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#define RP_LOCK_LOG_IS_ALREADY_LOCKED 1
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#define RP_FORCE_ROTATE 2
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The COPY_INFO structure is used by INSERT/REPLACE code.
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The schema of the row counting by the INSERT/INSERT ... ON DUPLICATE KEY
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If a row is inserted then the copied variable is incremented.
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If a row is updated by the INSERT ... ON DUPLICATE KEY UPDATE and the
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new data differs from the old one then the copied and the updated
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variables are incremented.
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The touched variable is incremented if a row was touched by the update part
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of the INSERT ... ON DUPLICATE KEY UPDATE no matter whether the row
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was actually changed or not.
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typedef struct st_copy_info {
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ha_rows records; /**< Number of processed records */
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ha_rows deleted; /**< Number of deleted records */
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ha_rows updated; /**< Number of updated records */
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ha_rows copied; /**< Number of copied records */
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ha_rows touched; /* Number of touched records */
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enum enum_duplicates handle_duplicates;
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int escape_char, last_errno;
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/* for INSERT ... UPDATE */
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List<Item> *update_fields;
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List<Item> *update_values;
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/* for VIEW ... WITH CHECK OPTION */
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class Key_part_spec :public Sql_alloc {
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LEX_STRING field_name;
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Key_part_spec(const LEX_STRING &name, uint32_t len)
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: field_name(name), length(len)
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Key_part_spec(const char *name, const size_t name_len, uint32_t len)
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{ field_name.str= (char *)name; field_name.length= name_len; }
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bool operator==(const Key_part_spec& other) const;
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Construct a copy of this Key_part_spec. field_name is copied
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by-pointer as it is known to never change. At the same time
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'length' may be reset in mysql_prepare_create_table, and this
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is why we supply it with a copy.
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@return If out of memory, 0 is returned and an error is set in
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Key_part_spec *clone(MEM_ROOT *mem_root) const
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{ return new (mem_root) Key_part_spec(*this); }
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class Alter_drop :public Sql_alloc {
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enum drop_type {KEY, COLUMN };
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Alter_drop(enum drop_type par_type,const char *par_name)
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:name(par_name), type(par_type) {}
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Used to make a clone of this object for ALTER/CREATE TABLE
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@sa comment for Key_part_spec::clone
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Alter_drop *clone(MEM_ROOT *mem_root) const
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{ return new (mem_root) Alter_drop(*this); }
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class Alter_column :public Sql_alloc {
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Alter_column(const char *par_name,Item *literal)
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:name(par_name), def(literal) {}
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Used to make a clone of this object for ALTER/CREATE TABLE
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@sa comment for Key_part_spec::clone
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Alter_column *clone(MEM_ROOT *mem_root) const
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{ return new (mem_root) Alter_column(*this); }
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class Key :public Sql_alloc {
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enum Keytype { PRIMARY, UNIQUE, MULTIPLE, FOREIGN_KEY};
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KEY_CREATE_INFO key_create_info;
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List<Key_part_spec> columns;
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Key(enum Keytype type_par, const LEX_STRING &name_arg,
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KEY_CREATE_INFO *key_info_arg,
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bool generated_arg, List<Key_part_spec> &cols)
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:type(type_par), key_create_info(*key_info_arg), columns(cols),
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name(name_arg), generated(generated_arg)
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Key(enum Keytype type_par, const char *name_arg, size_t name_len_arg,
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KEY_CREATE_INFO *key_info_arg, bool generated_arg,
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List<Key_part_spec> &cols)
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:type(type_par), key_create_info(*key_info_arg), columns(cols),
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generated(generated_arg)
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name.str= (char *)name_arg;
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name.length= name_len_arg;
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Key(const Key &rhs, MEM_ROOT *mem_root);
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/* Equality comparison of keys (ignoring name) */
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friend bool foreign_key_prefix(Key *a, Key *b);
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Used to make a clone of this object for ALTER/CREATE TABLE
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@sa comment for Key_part_spec::clone
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virtual Key *clone(MEM_ROOT *mem_root) const
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{ return new (mem_root) Key(*this, mem_root); }
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class Foreign_key: public Key {
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enum fk_match_opt { FK_MATCH_UNDEF, FK_MATCH_FULL,
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FK_MATCH_PARTIAL, FK_MATCH_SIMPLE};
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enum fk_option { FK_OPTION_UNDEF, FK_OPTION_RESTRICT, FK_OPTION_CASCADE,
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FK_OPTION_SET_NULL, FK_OPTION_NO_ACTION, FK_OPTION_DEFAULT};
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Table_ident *ref_table;
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List<Key_part_spec> ref_columns;
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uint32_t delete_opt, update_opt, match_opt;
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Foreign_key(const LEX_STRING &name_arg, List<Key_part_spec> &cols,
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Table_ident *table, List<Key_part_spec> &ref_cols,
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uint32_t delete_opt_arg, uint32_t update_opt_arg, uint32_t match_opt_arg)
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:Key(FOREIGN_KEY, name_arg, &default_key_create_info, 0, cols),
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ref_table(table), ref_columns(ref_cols),
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delete_opt(delete_opt_arg), update_opt(update_opt_arg),
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match_opt(match_opt_arg)
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Foreign_key(const Foreign_key &rhs, MEM_ROOT *mem_root);
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Used to make a clone of this object for ALTER/CREATE TABLE
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@sa comment for Key_part_spec::clone
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virtual Key *clone(MEM_ROOT *mem_root) const
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{ return new (mem_root) Foreign_key(*this, mem_root); }
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typedef struct st_mysql_lock
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uint32_t table_count,lock_count;
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THR_LOCK_DATA **locks;
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class LEX_COLUMN : public Sql_alloc
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LEX_COLUMN (const String& x,const uint& y ): column (x),rights (y) {}
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#define THD_SENTRY_MAGIC 0xfeedd1ff
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#define THD_SENTRY_GONE 0xdeadbeef
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#define THD_CHECK_SENTRY(thd) assert(thd->dbug_sentry == THD_SENTRY_MAGIC)
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struct system_variables
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How dynamically allocated system variables are handled:
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The global_system_variables and max_system_variables are "authoritative"
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They both should have the same 'version' and 'size'.
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When attempting to access a dynamic variable, if the session version
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is out of date, then the session version is updated and realloced if
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neccessary and bytes copied from global to make up for missing data.
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ulong dynamic_variables_version;
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char* dynamic_variables_ptr;
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uint32_t dynamic_variables_head; /* largest valid variable offset */
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uint32_t dynamic_variables_size; /* how many bytes are in use */
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uint64_t myisam_max_extra_sort_file_size;
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uint64_t myisam_max_sort_file_size;
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uint64_t max_heap_table_size;
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uint64_t tmp_table_size;
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uint64_t long_query_time;
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ha_rows select_limit;
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ha_rows max_join_size;
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ulong auto_increment_increment, auto_increment_offset;
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ulong bulk_insert_buff_size;
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ulong join_buff_size;
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ulong max_allowed_packet;
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ulong max_error_count;
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ulong max_length_for_sort_data;
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ulong max_sort_length;
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ulong max_tmp_tables;
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ulong min_examined_row_limit;
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ulong myisam_repair_threads;
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ulong myisam_sort_buff_size;
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ulong myisam_stats_method;
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ulong net_buffer_length;
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ulong net_interactive_timeout;
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ulong net_read_timeout;
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ulong net_retry_count;
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ulong net_wait_timeout;
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ulong net_write_timeout;
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ulong optimizer_prune_level;
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ulong optimizer_search_depth;
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Controls use of Engine-MRR:
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0 - auto, based on cost
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1 - force MRR when the storage engine is capable of doing it
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ulong optimizer_use_mrr;
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/* A bitmap for switching optimizations on/off */
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ulong optimizer_switch;
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ulong preload_buff_size;
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ulong profiling_history_size;
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ulong query_cache_type;
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ulong read_buff_size;
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ulong read_rnd_buff_size;
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ulong div_precincrement;
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ulong thread_handling;
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ulong completion_type;
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/* Determines which non-standard SQL behaviour should be enabled */
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ulong default_week_format;
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ulong max_seeks_for_key;
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ulong range_alloc_block_size;
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ulong query_alloc_block_size;
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ulong query_prealloc_size;
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ulong trans_alloc_block_size;
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ulong trans_prealloc_size;
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ulong group_concat_max_len;
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ulong binlog_format; // binlog format for this thd (see enum_binlog_format)
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In slave thread we need to know in behalf of which
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thread the query is being run to replicate temp tables properly
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my_thread_id pseudo_thread_id;
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bool low_priority_updates;
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compatibility option:
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- index usage hints (USE INDEX without a FOR clause) behave as in 5.0
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bool engine_condition_pushdown;
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bool keep_files_on_create;
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bool old_alter_table;
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plugin_ref table_plugin;
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/* Only charset part of these variables is sensible */
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const CHARSET_INFO *character_set_filesystem;
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const CHARSET_INFO *character_set_client;
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const CHARSET_INFO *character_set_results;
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/* Both charset and collation parts of these variables are important */
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const CHARSET_INFO *collation_server;
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const CHARSET_INFO *collation_database;
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const CHARSET_INFO *collation_connection;
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MY_LOCALE *lc_time_names;
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Time_zone *time_zone;
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/* DATE, DATETIME and DRIZZLE_TIME formats */
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DATE_TIME_FORMAT *date_format;
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DATE_TIME_FORMAT *datetime_format;
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DATE_TIME_FORMAT *time_format;
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#include "sql_lex.h" /* only for SQLCOM_END */
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/* per thread status variables */
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typedef struct system_status_var
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uint64_t bytes_received;
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ulong com_stat[(uint) SQLCOM_END];
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ulong created_tmp_disk_tables;
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ulong created_tmp_tables;
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ulong ha_commit_count;
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ulong ha_delete_count;
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ulong ha_read_first_count;
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ulong ha_read_last_count;
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ulong ha_read_key_count;
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ulong ha_read_next_count;
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ulong ha_read_prev_count;
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ulong ha_read_rnd_count;
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ulong ha_read_rnd_next_count;
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ulong ha_rollback_count;
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ulong ha_update_count;
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ulong ha_write_count;
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ulong ha_prepare_count;
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ulong ha_discover_count;
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ulong ha_savepoint_count;
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ulong ha_savepoint_rollback_count;
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/* KEY_CACHE parts. These are copies of the original */
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ulong key_blocks_changed;
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ulong key_blocks_used;
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ulong key_cache_r_requests;
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ulong key_cache_read;
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ulong key_cache_w_requests;
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ulong key_cache_write;
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/* END OF KEY_CACHE parts */
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ulong net_big_packet_count;
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ulong select_full_join_count;
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ulong select_full_range_join_count;
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ulong select_range_count;
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ulong select_range_check_count;
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ulong select_scan_count;
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ulong long_query_count;
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ulong filesort_merge_passes;
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ulong filesort_range_count;
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ulong filesort_scan_count;
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/* Prepared statements and binary protocol */
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ulong com_stmt_prepare;
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ulong com_stmt_execute;
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ulong com_stmt_send_long_data;
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ulong com_stmt_fetch;
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ulong com_stmt_reset;
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ulong com_stmt_close;
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Number of statements sent from the client
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SEE last_system_status_var DEFINITION BELOW.
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Below 'last_system_status_var' are all variables which doesn't make any
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sense to add to the /global/ status variable counter.
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double last_query_cost;
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This is used for 'SHOW STATUS'. It must be updated to the last ulong
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variable in system_status_var which is makes sens to add to the global
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#define last_system_status_var questions
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void mark_transaction_to_rollback(THD *thd, bool all);
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#ifdef DRIZZLE_SERVER
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List of items created in the parser for this query. Every item puts
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itself to the list on creation (see Item::Item() for details))
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MEM_ROOT *mem_root; // Pointer to current memroot
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Query_arena(MEM_ROOT *mem_root_arg) :
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free_list(0), mem_root(mem_root_arg)
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This constructor is used only when Query_arena is created as
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backup storage for another instance of Query_arena.
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virtual ~Query_arena() {};
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inline void* alloc(size_t size) { return alloc_root(mem_root,size); }
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inline void* calloc(size_t size)
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if ((ptr=alloc_root(mem_root,size)))
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memset(ptr, 0, size);
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inline char *strdup(const char *str)
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{ return strdup_root(mem_root,str); }
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inline char *strmake(const char *str, size_t size)
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{ return strmake_root(mem_root,str,size); }
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inline void *memdup(const void *str, size_t size)
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{ return memdup_root(mem_root,str,size); }
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inline void *memdup_w_gap(const void *str, size_t size, uint32_t gap)
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if ((ptr= alloc_root(mem_root,size+gap)))
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memcpy(ptr,str,size);
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* Represents a client connection to the database server.
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* Contains the client/server protocol object, the current statement
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* being executed, local-to-session variables and status counters, and
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* a host of other information.
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* The Session class should have a vector of Statement object pointers which
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* comprise the statements executed on the Session. Until this architectural
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* change is done, we can forget about parallel operations inside a session.
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* Make member variables private and have inlined accessors and setters. Hide
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* all member variables that are not critical to non-internal operations of the
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class DRIZZLED_API Session : public Open_tables_state
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@brief State of a single command executed against this connection.
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One connection can contain a lot of simultaneously running statements,
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some of which could be:
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- prepared, that is, contain placeholders,
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To perform some action with statement we reset THD part to the state of
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that statement, do the action, and then save back modified state from THD
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to the statement. It will be changed in near future, and Statement will
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class Statement: public ilink, public Query_arena
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Statement(const Statement &rhs); /* not implemented: */
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Statement &operator=(const Statement &rhs); /* non-copyable */
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// Plugin storage in Session.
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typedef boost::shared_ptr<Session> shared_ptr;
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typedef Session& reference;
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typedef const Session& const_reference;
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typedef const Session* const_pointer;
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typedef Session* pointer;
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static shared_ptr make_shared(plugin::Client *client, catalog::Instance::shared_ptr instance_arg)
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assert(instance_arg);
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return boost::make_shared<Session>(client, instance_arg);
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Uniquely identifies each statement object in thread scope; change during
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statement lifetime. FIXME: must be const
151
519
MARK_COLUMNS_NONE: Means mark_used_colums is not set and no indicator to
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520
handler of fields used is set
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MARK_COLUMNS_READ: Means a bit in read set is set to inform handler
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that the field is to be read. If field list contains
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duplicates, then session->dup_field is set to point
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duplicates, then thd->dup_field is set to point
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to the last found duplicate.
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MARK_COLUMNS_WRITE: Means a bit is set in write set to inform handler
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526
that it needs to update this field in write_row
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enum enum_mark_columns mark_used_columns;
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inline void* calloc(size_t size)
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if ((ptr= mem_root->alloc_root(size)))
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memset(ptr, 0, size);
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inline char *strmake(const char *str, size_t size)
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return mem_root->strmake_root(str,size);
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inline void *memdup_w_gap(const void *str, size_t size, uint32_t gap)
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if ((ptr= mem_root->alloc_root(size + gap)))
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memcpy(ptr,str,size);
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/** Frees all items attached to this Statement */
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* List of items created in the parser for this query. Every item puts
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* itself to the list on creation (see Item::Item() for details))
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memory::Root *mem_root; /**< Pointer to current memroot */
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memory::Root *getMemRoot()
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void setXaId(uint64_t in_xa_id)
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* Uniquely identifies each statement object in thread scope; change during
211
* statement lifetime.
213
* @todo should be const
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LEX *lex; /**< parse tree descriptor */
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enum_sql_command getSqlCommand() const
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return lex->sql_command;
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/** query associated with this statement */
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typedef boost::shared_ptr<const std::string> QueryString;
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boost::shared_ptr<std::string> query;
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// Never allow for a modification of this outside of the class. c_str()
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// requires under some setup non const, you must copy the QueryString in
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QueryString getQueryString() const
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void resetQueryString()
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LEX *lex; // parse tree descriptor
252
We need to copy the lock on the string in order to make sure we have a stable string.
253
Once this is done we can use it to build a const char* which can be handed off for
254
a method to use (Innodb is currently the only engine using this).
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Points to the query associated with this statement. It's const, but
534
we need to declare it char * because all table handlers are written
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in C and need to point to it.
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Note that (A) if we set query = NULL, we must at the same time set
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query_length = 0, and protect the whole operation with the
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LOCK_thread_count mutex. And (B) we are ONLY allowed to set query to a
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non-NULL value if its previous value is NULL. We do not need to protect
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operation (B) with any mutex. To avoid crashes in races, if we do not
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know that thd->query cannot change at the moment, one should print
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thd->query like this:
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(1) reserve the LOCK_thread_count mutex;
545
(2) check if thd->query is NULL;
546
(3) if not NULL, then print at most thd->query_length characters from
547
it. We will see the query_length field as either 0, or the right value
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Assuming that the write and read of an n-bit memory field in an n-bit
550
computer is atomic, we can avoid races in the above way.
551
This printing is needed at least in SHOW PROCESSLIST and SHOW INNODB
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const char *getQueryStringCopy(size_t &length)
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QueryString tmp_string(getQueryString());
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length= tmp_string->length();
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char *to_return= strmake(tmp_string->c_str(), tmp_string->length());
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session::State::shared_ptr _state;
276
session::State::const_shared_ptr state()
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uint32_t query_length; // current query length
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558
Name of the current (default) database.
287
563
valid database name.
289
565
@note this attribute is set and alloced by the slave SQL thread (for
290
the Session of that thread); that thread is (and must remain, for now) the
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the THD of that thread); that thread is (and must remain, for now) the
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only responsible for freeing this member.
575
/* This constructor is called for backup statements */
578
Statement(LEX *lex_arg, MEM_ROOT *mem_root_arg, ulong id_arg);
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struct st_savepoint {
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struct st_savepoint *prev;
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Ha_trx_info *ha_list;
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enum xa_states {XA_NOTR=0, XA_ACTIVE, XA_IDLE, XA_PREPARED};
590
extern const char *xa_state_names[];
592
typedef struct st_xid_state {
593
/* For now, this is only used to catch duplicated external xids */
594
XID xid; // transaction identifier
595
enum xa_states xa_state; // used by external XA only
599
extern pthread_mutex_t LOCK_xid_cache;
600
extern HASH xid_cache;
601
bool xid_cache_init(void);
602
void xid_cache_free(void);
603
XID_STATE *xid_cache_search(XID *xid);
604
bool xid_cache_insert(XID *xid, enum xa_states xa_state);
605
bool xid_cache_insert(XID_STATE *xid_state);
606
void xid_cache_delete(XID_STATE *xid_state);
609
@class Security_context
610
@brief A set of THD members describing the current authenticated user.
613
class Security_context {
615
Security_context() {} /* Remove gcc warning */
617
host - host of the client
618
user - user of the client, set to NULL until the user has been read from
620
priv_user - The user privilege we are using. May be "" for anonymous user.
629
inline char *priv_host_name()
631
return (ip ? ip : (char *)"%");
637
A registry for item tree transformations performed during
638
query optimization. We register only those changes which require
639
a rollback to re-execute a prepared statement or stored procedure
643
struct Item_change_record;
644
typedef I_List<Item_change_record> Item_change_list;
648
Class that holds information about tables which were opened and locked
649
by the thread. It is also used to save/restore this information in
650
push_open_tables_state()/pop_open_tables_state().
653
class Open_tables_state
657
List of regular tables in use by this thread. Contains temporary and
658
base tables that were opened with @see open_tables().
662
List of temporary tables used by this thread. Contains user-level
663
temporary tables, created with CREATE TEMPORARY TABLE, and
664
internal temporary tables, created, e.g., to resolve a SELECT,
665
or for an intermediate table used in ALTER.
666
XXX Why are internal temporary tables added to this list?
668
Table *temporary_tables;
670
List of tables that were opened with HANDLER OPEN and are
671
still in use by this thread.
673
Table *handler_tables;
674
Table *derived_tables;
676
During a MySQL session, one can lock tables in two modes: automatic
677
or manual. In automatic mode all necessary tables are locked just before
678
statement execution, and all acquired locks are stored in 'lock'
679
member. Unlocking takes place automatically as well, when the
681
Manual mode comes into play when a user issues a 'LOCK TABLES'
682
statement. In this mode the user can only use the locked tables.
683
Trying to use any other tables will give an error. The locked tables are
684
stored in 'locked_tables' member. Manual locking is described in
685
the 'LOCK_TABLES' chapter of the MySQL manual.
686
See also lock_tables() for details.
690
Tables that were locked with explicit or implicit LOCK TABLES.
691
(Implicit LOCK TABLES happens when we are prelocking tables for
692
execution of statement which uses stored routines. See description
693
THD::prelocked_mode for more info.)
695
DRIZZLE_LOCK *locked_tables;
698
CREATE-SELECT keeps an extra lock for the table being
699
created. This field is used to keep the extra lock available for
700
lower level routines, which would otherwise miss that lock.
702
DRIZZLE_LOCK *extra_lock;
705
uint32_t current_tablenr;
708
BACKUPS_AVAIL = (1U << 0) /* There are backups available */
712
Flags with information about the open tables state.
714
uint32_t state_flags;
717
This constructor serves for creation of Open_tables_state instances
718
which are used as backup storage.
720
Open_tables_state() : state_flags(0U) { }
722
Open_tables_state(ulong version_arg);
724
void set_open_tables_state(Open_tables_state *state)
729
void reset_open_tables_state()
731
open_tables= temporary_tables= handler_tables= derived_tables= 0;
732
extra_lock= lock= locked_tables= 0;
738
/* Flags for the THD::system_thread variable */
739
enum enum_thread_type
742
SYSTEM_THREAD_SLAVE_IO,
743
SYSTEM_THREAD_SLAVE_SQL
748
This class represents the interface for internal error handlers.
749
Internal error handlers are exception handlers used by the server
752
class Internal_error_handler
755
Internal_error_handler() {}
756
virtual ~Internal_error_handler() {}
760
Handle an error condition.
761
This method can be implemented by a subclass to achieve any of the
763
- mask an error internally, prevent exposing it to the user,
764
- mask an error and throw another one instead.
765
When this method returns true, the error condition is considered
766
'handled', and will not be propagated to upper layers.
767
It is the responsability of the code installing an internal handler
768
to then check for trapped conditions, and implement logic to recover
769
from the anticipated conditions trapped during runtime.
771
This mechanism is similar to C++ try/throw/catch:
772
- 'try' correspond to <code>THD::push_internal_handler()</code>,
773
- 'throw' correspond to <code>my_error()</code>,
774
which invokes <code>my_message_sql()</code>,
775
- 'catch' correspond to checking how/if an internal handler was invoked,
776
before removing it from the exception stack with
777
<code>THD::pop_internal_handler()</code>.
779
@param sql_errno the error number
780
@param level the error level
781
@param thd the calling thread
782
@return true if the error is handled
784
virtual bool handle_error(uint32_t sql_errno,
786
DRIZZLE_ERROR::enum_warning_level level,
792
Stores status of the currently executed statement.
793
Cleared at the beginning of the statement, and then
794
can hold either OK, ERROR, or EOF status.
795
Can not be assigned twice per statement.
798
class Diagnostics_area
801
enum enum_diagnostics_status
803
/** The area is cleared at start of a statement. */
805
/** Set whenever one calls my_ok(). */
807
/** Set whenever one calls my_eof(). */
809
/** Set whenever one calls my_error() or my_message(). */
811
/** Set in case of a custom response, such as one from COM_STMT_PREPARE. */
814
/** True if status information is sent to the client. */
816
/** Set to make set_error_status after set_{ok,eof}_status possible. */
817
bool can_overwrite_status;
819
void set_ok_status(THD *thd, ha_rows affected_rows_arg,
820
uint64_t last_insert_id_arg,
821
const char *message);
822
void set_eof_status(THD *thd);
823
void set_error_status(THD *thd, uint32_t sql_errno_arg, const char *message_arg);
825
void disable_status();
827
void reset_diagnostics_area();
829
bool is_set() const { return m_status != DA_EMPTY; }
830
bool is_error() const { return m_status == DA_ERROR; }
831
bool is_eof() const { return m_status == DA_EOF; }
832
bool is_ok() const { return m_status == DA_OK; }
833
bool is_disabled() const { return m_status == DA_DISABLED; }
834
enum_diagnostics_status status() const { return m_status; }
836
const char *message() const
837
{ assert(m_status == DA_ERROR || m_status == DA_OK); return m_message; }
839
uint32_t sql_errno() const
840
{ assert(m_status == DA_ERROR); return m_sql_errno; }
842
uint32_t server_status() const
844
assert(m_status == DA_OK || m_status == DA_EOF);
845
return m_server_status;
848
ha_rows affected_rows() const
849
{ assert(m_status == DA_OK); return m_affected_rows; }
851
uint64_t last_insert_id() const
852
{ assert(m_status == DA_OK); return m_last_insert_id; }
854
uint32_t total_warn_count() const
856
assert(m_status == DA_OK || m_status == DA_EOF);
857
return m_total_warn_count;
860
Diagnostics_area() { reset_diagnostics_area(); }
294
util::string::shared_ptr _schema;
863
/** Message buffer. Can be used by OK or ERROR status. */
864
char m_message[DRIZZLE_ERRMSG_SIZE];
866
SQL error number. One of ER_ codes from share/errmsg.txt.
867
Set by set_error_status.
869
uint32_t m_sql_errno;
872
Copied from thd->server_status when the diagnostics area is assigned.
873
We need this member as some places in the code use the following pattern:
874
thd->server_status|= ...
876
thd->server_status&= ~...
877
Assigned by OK, EOF or ERROR.
879
uint32_t m_server_status;
881
The number of rows affected by the last statement. This is
882
semantically close to thd->row_count_func, but has a different
883
life cycle. thd->row_count_func stores the value returned by
884
function ROW_COUNT() and is cleared only by statements that
885
update its value, such as INSERT, UPDATE, DELETE and few others.
886
This member is cleared at the beginning of the next statement.
888
We could possibly merge the two, but life cycle of thd->row_count_func
891
ha_rows m_affected_rows;
893
Similarly to the previous member, this is a replacement of
894
thd->first_successful_insert_id_in_prev_stmt, which is used
895
to implement LAST_INSERT_ID().
897
uint64_t m_last_insert_id;
898
/** The total number of warnings. */
899
uint m_total_warn_count;
900
enum_diagnostics_status m_status;
902
@todo: the following THD members belong here:
903
- warn_list, warn_count,
909
Storage engine specific thread local data.
915
Storage engine specific thread local data.
916
Lifetime: one user connection.
920
0: Life time: one statement within a transaction. If @@autocommit is
921
on, also represents the entire transaction.
922
@sa trans_register_ha()
924
1: Life time: one transaction within a connection.
925
If the storage engine does not participate in a transaction,
926
this should not be used.
927
@sa trans_register_ha()
929
Ha_trx_info ha_info[2];
931
Ha_data() :ha_ptr(NULL) {}
937
For each client connection we create a separate thread with THD serving as
938
a thread/connection descriptor
941
class THD :public Statement,
942
public Open_tables_state
298
util::string::const_shared_ptr schema() const
303
return util::string::const_shared_ptr(new std::string(""));
306
/* current cache key */
307
std::string query_cache_key;
309
Constant for Session::where initialization in the beginning of every query.
311
It's needed because we do not save/restore Session::where normally during
945
/* Used to execute base64 coded binlog events in MySQL server */
946
Relay_log_info* rli_fake;
949
Constant for THD::where initialization in the beginning of every query.
951
It's needed because we do not save/restore THD::where normally during
312
952
primary (non subselect) query execution.
314
954
static const char * const DEFAULT_WHERE;
316
memory::Root warn_root; /**< Allocation area for warnings and errors */
318
plugin::Client *client; /**< Pointer to client object */
322
void setClient(plugin::Client *client_arg);
324
plugin::Client *getClient()
329
plugin::Client *getClient() const
334
plugin::Scheduler *scheduler; /**< Pointer to scheduler object */
335
void *scheduler_arg; /**< Pointer to the optional scheduler argument */
337
typedef boost::unordered_map< std::string, user_var_entry *, util::insensitive_hash, util::insensitive_equal_to> UserVars;
340
typedef std::pair< UserVars::iterator, UserVars::iterator > UserVarsRange;
341
UserVars user_vars; /**< Hash of user variables defined during the session's lifetime */
344
const UserVars &getUserVariables() const
349
drizzle_system_variables variables; /**< Mutable local variables local to the session */
351
enum_tx_isolation getTxIsolation()
353
return (enum_tx_isolation)variables.tx_isolation;
356
struct system_status_var status_var; /**< Session-local status counters */
357
THR_LOCK_INFO lock_info; /**< Locking information for this session */
358
THR_LOCK_OWNER main_lock_id; /**< To use for conventional queries */
359
THR_LOCK_OWNER *lock_id; /**< If not main_lock_id, points to the lock_id of a cursor. */
362
* A pointer to the stack frame of the scheduler thread
363
* which is called first in the thread for handling a client
368
identifier::User::shared_ptr security_ctx;
370
int32_t scoreboard_index;
372
inline void checkSentry() const
374
assert(this->dbug_sentry == Session_SENTRY_MAGIC);
378
identifier::User::const_shared_ptr user() const
383
return identifier::User::const_shared_ptr();
386
void setUser(identifier::User::shared_ptr arg)
391
int32_t getScoreboardIndex()
393
return scoreboard_index;
396
void setScoreboardIndex(int32_t in_scoreboard_index)
398
scoreboard_index= in_scoreboard_index;
402
* Is this session viewable by the current user?
404
bool isViewable(identifier::User::const_reference) const;
956
NET net; // client connection descriptor
957
MEM_ROOT warn_root; // For warnings and errors
958
Protocol *protocol; // Current protocol
959
Protocol_text protocol_text; // Normal protocol
960
HASH user_vars; // hash for user variables
961
String packet; // dynamic buffer for network I/O
962
String convert_buffer; // buffer for charset conversions
963
struct rand_struct rand; // used for authentication
964
struct system_variables variables; // Changeable local variables
965
struct system_status_var status_var; // Per thread statistic vars
966
struct system_status_var *initial_status_var; /* used by show status */
967
THR_LOCK_INFO lock_info; // Locking info of this thread
968
THR_LOCK_OWNER main_lock_id; // To use for conventional queries
969
THR_LOCK_OWNER *lock_id; // If not main_lock_id, points to
970
// the lock_id of a cursor.
971
pthread_mutex_t LOCK_delete; // Locked before thd is deleted
973
A pointer to the stack frame of handle_one_connection(),
974
which is called first in the thread for handling a client
979
Currently selected catalog.
985
Some members of THD (currently 'Statement::db',
986
'catalog' and 'query') are set and alloced by the slave SQL thread
987
(for the THD of that thread); that thread is (and must remain, for now)
988
the only responsible for freeing these 3 members. If you add members
989
here, and you add code to set them in replication, don't forget to
990
free_them_and_set_them_to_0 in replication properly. For details see
991
the 'err:' label of the handle_slave_sql() in sql/slave.cc.
993
@see handle_slave_sql
996
Security_context main_security_ctx;
997
Security_context *security_ctx;
1000
Points to info-string that we show in SHOW PROCESSLIST
1001
You are supposed to call THD_SET_PROC_INFO only if you have coded
1002
a time-consuming piece that MySQL can get stuck in for a long time.
1004
Set it using the thd_proc_info(THD *thread, const char *message)
1007
void set_proc_info(const char *info) { proc_info= info; }
1008
const char* get_proc_info() const { return proc_info; }
408
1011
Used in error messages to tell user in what part of MySQL we found an
409
1012
error. E. g. when where= "having clause", if fix_fields() fails, user
410
1013
will know that the error was in having clause.
420
void setWhere(const char *arg)
1017
double tmp_double_value; /* Used in set_var.cc */
1018
ulong client_capabilities; /* What the client supports */
1019
ulong max_client_packet_length;
1021
HASH handler_tables_hash;
426
1023
One thread can hold up to one named user-level lock. This variable
427
1024
points to a lock object if the lock is present. See item_func.cc and
428
chapter 'Miscellaneous functions', for functions GET_LOCK, RELEASE_LOCK.
430
uint32_t dbug_sentry; /**< watch for memory corruption */
433
boost::thread::id boost_thread_id;
434
boost_thread_shared_ptr _thread;
435
boost::this_thread::disable_interruption *interrupt;
437
internal::st_my_thread_var *mysys_var;
440
boost_thread_shared_ptr &getThread()
445
void pushInterrupt(boost::this_thread::disable_interruption *interrupt_arg)
447
interrupt= interrupt_arg;
450
boost::this_thread::disable_interruption &getThreadInterupt()
456
internal::st_my_thread_var *getThreadVar()
462
* Type of current query: COM_STMT_PREPARE, COM_QUERY, etc. Set from
463
* first byte of the packet in executeStatement()
1025
chapter 'Miscellaneous functions', for functions GET_LOCK, RELEASE_LOCK.
1027
uint32_t dbug_sentry; // watch out for memory corruption
1028
struct st_my_thread_var *mysys_var;
1030
Type of current query: COM_STMT_PREPARE, COM_QUERY, etc. Set from
1031
first byte of the packet in do_command()
465
1033
enum enum_server_command command;
466
uint32_t file_id; /**< File ID for LOAD DATA INFILE */
467
/* @note the following three members should likely move to Client */
468
uint32_t max_client_packet_length; /**< Maximum number of bytes a client can send in a single packet */
471
boost::posix_time::ptime _epoch;
472
boost::posix_time::ptime _connect_time;
473
boost::posix_time::ptime _start_timer;
474
boost::posix_time::ptime _end_timer;
476
boost::posix_time::ptime _user_time;
478
uint64_t utime_after_lock; // This used by Innodb.
482
_user_time= boost::posix_time::not_a_date_time;
485
const boost::posix_time::ptime &start_timer() const
490
void getTimeDifference(boost::posix_time::time_duration &result_arg, const boost::posix_time::ptime &arg) const
492
result_arg= arg - _start_timer;
1035
uint32_t file_id; // for LOAD DATA INFILE
1036
/* remote (peer) port */
1038
time_t start_time, user_time;
1039
uint64_t connect_utime, thr_create_utime; // track down slow pthread_create
1040
uint64_t start_utime, utime_after_lock;
495
1042
thr_lock_type update_lock_default;
498
Both of the following container points in session will be converted to an API.
1044
/* <> 0 if we are inside of trigger or stored function. */
1045
uint32_t in_sub_stmt;
502
1047
/* container for handler's private per-connection data */
503
std::vector<Ha_data> ha_data;
505
Id of current query. Statement can be reused to execute several queries
506
query_id is global in context of the whole MySQL server.
507
ID is automatically generated from an atomic counter.
508
It's used in Cursor code for various purposes: to check which columns
509
from table are necessary for this select, to check if it's necessary to
510
update auto-updatable fields (like auto_increment and timestamp).
513
query_id_t warn_query_id;
516
void **getEngineData(const plugin::MonitoredInTransaction *monitored);
517
ResourceContext *getResourceContext(const plugin::MonitoredInTransaction *monitored,
520
session::Transactions transaction;
1048
Ha_data ha_data[MAX_HA];
1050
/* Place to store various things */
1052
int binlog_setup_trx_data();
1055
Public interface to write RBR events to the binlog
1057
void binlog_start_trans_and_stmt();
1058
void binlog_set_stmt_begin();
1059
int binlog_write_table_map(Table *table, bool is_transactional);
1060
int binlog_write_row(Table* table, bool is_transactional,
1061
const unsigned char *new_data);
1062
int binlog_delete_row(Table* table, bool is_transactional,
1063
const unsigned char *old_data);
1064
int binlog_update_row(Table* table, bool is_transactional,
1065
const unsigned char *old_data, const unsigned char *new_data);
1067
void set_server_id(uint32_t sid) { server_id = sid; }
1070
Member functions to handle pending event for row-level logging.
1072
template <class RowsEventT> Rows_log_event*
1073
binlog_prepare_pending_rows_event(Table* table, uint32_t serv_id,
1075
bool is_transactional,
1077
Rows_log_event* binlog_get_pending_rows_event() const;
1078
void binlog_set_pending_rows_event(Rows_log_event* ev);
1079
int binlog_flush_pending_rows_event(bool stmt_end);
1082
uint32_t binlog_table_maps; // Number of table maps currently in the binlog
1084
enum enum_binlog_flag {
1085
BINLOG_FLAG_UNSAFE_STMT_PRINTED,
1090
Flags with per-thread information regarding the status of the
1093
uint32_t binlog_flags;
1095
uint32_t get_binlog_table_maps() const {
1096
return binlog_table_maps;
1098
void clear_binlog_table_maps() {
1099
binlog_table_maps= 0;
1104
struct st_transactions {
1105
SAVEPOINT *savepoints;
1106
THD_TRANS all; // Trans since BEGIN WORK
1107
THD_TRANS stmt; // Trans for current statement
1108
bool on; // see ha_enable_transaction()
1109
XID_STATE xid_state;
1110
Rows_log_event *m_pending_rows_event;
1113
Tables changed in transaction (that must be invalidated in query cache).
1114
List contain only transactional tables, that not invalidated in query
1115
cache (instead of full list of changed in transaction tables).
1117
CHANGED_TableList* changed_tables;
1118
MEM_ROOT mem_root; // Transaction-life memory allocation pool
1123
free_root(&mem_root,MYF(MY_KEEP_PREALLOC));
1127
memset(this, 0, sizeof(*this));
1128
xid_state.xid.null();
1129
init_sql_alloc(&mem_root, ALLOC_ROOT_MIN_BLOCK_SIZE, 0);
523
1133
sigset_t signals;
525
// As of right now we do not allow a concurrent execute to launch itself
527
bool concurrent_execute_allowed;
531
void setConcurrentExecute(bool arg)
533
concurrent_execute_allowed= arg;
536
bool isConcurrentExecuteAllowed() const
538
return concurrent_execute_allowed;
1135
This is to track items changed during execution of a prepared
1136
statement/stored procedure. It's created by
1137
register_item_tree_change() in memory root of THD, and freed in
1138
rollback_item_tree_changes(). For conventional execution it's always
1141
Item_change_list change_list;
541
1143
/* Tells if LAST_INSERT_ID(#) was called for the current statement */
542
1144
bool arg_of_last_insert_id_function;
545
1146
ALL OVER THIS FILE, "insert_id" means "*automatically generated* value for
546
1147
insertion into an auto_increment column".
549
1150
This is the first autogenerated insert id which was *successfully*
550
1151
inserted by the previous statement (exactly, if the previous statement
551
1152
didn't successfully insert an autogenerated insert id, then it's the one
588
1209
in the binlog is still needed; the list's minimum will contain 3.
590
1211
Discrete_intervals_list auto_inc_intervals_in_cur_stmt_for_binlog;
591
/** Used by replication and SET INSERT_ID */
1212
/* Used by replication and SET INSERT_ID */
592
1213
Discrete_intervals_list auto_inc_intervals_forced;
594
uint64_t limit_found_rows;
595
uint64_t options; /**< Bitmap of options */
596
int64_t row_count_func; /**< For the ROW_COUNT() function */
598
int64_t rowCount() const
600
return row_count_func;
603
ha_rows cuted_fields; /**< Count of "cut" or truncated fields. @todo Kill this friggin thing. */
606
* Number of rows we actually sent to the client, including "synthetic"
607
* rows in ROLLUP etc.
609
ha_rows sent_row_count;
612
* Number of rows we read, sent or not, including in create_sort_index()
614
ha_rows examined_row_count;
617
* The set of those tables whose fields are referenced in all subqueries
622
* Possibly this it is incorrect to have used tables in Session because
623
* with more than one subquery, it is not clear what does the field mean.
625
table_map used_tables;
630
This, and some other variables like 'count_cuted_fields'
631
maybe should be statement/cursor local, that is, moved to Statement
632
class. With current implementation warnings produced in each prepared
633
statement/cursor settle here.
635
List<DRIZZLE_ERROR> warn_list;
636
uint32_t warn_count[(uint32_t) DRIZZLE_ERROR::WARN_LEVEL_END];
637
uint32_t total_warn_count;
638
Diagnostics_area main_da;
642
/* Statement id is thread-wide. This counter is used to generate ids */
643
uint32_t statement_id_counter;
644
uint32_t rand_saved_seed1;
645
uint32_t rand_saved_seed2;
647
Row counter, mainly for errors and warnings. Not increased in
648
create_sort_index(); may differ from examined_row_count.
652
uint32_t getRowCount() const
657
session_id_t thread_id;
659
enum global_read_lock_t
662
GOT_GLOBAL_READ_LOCK= 1,
663
MADE_GLOBAL_READ_LOCK_BLOCK_COMMIT= 2
666
global_read_lock_t _global_read_lock;
670
global_read_lock_t isGlobalReadLock() const
672
return _global_read_lock;
675
void setGlobalReadLock(global_read_lock_t arg)
677
_global_read_lock= arg;
680
DrizzleLock *lockTables(Table **tables, uint32_t count, uint32_t flags);
681
bool lockGlobalReadLock();
682
bool lock_table_names(TableList *table_list);
683
bool lock_table_names_exclusively(TableList *table_list);
684
bool makeGlobalReadLockBlockCommit();
685
bool abortLockForThread(Table *table);
686
bool wait_if_global_read_lock(bool abort_on_refresh, bool is_not_commit);
687
int lock_table_name(TableList *table_list);
688
void abortLock(Table *table);
689
void removeLock(Table *table);
690
void unlockReadTables(DrizzleLock *sql_lock);
691
void unlockSomeTables(Table **table, uint32_t count);
692
void unlockTables(DrizzleLock *sql_lock);
693
void startWaitingGlobalReadLock();
694
void unlockGlobalReadLock();
697
int unlock_external(Table **table, uint32_t count);
698
int lock_external(Table **tables, uint32_t count);
699
bool wait_for_locked_table_names(TableList *table_list);
700
DrizzleLock *get_lock_data(Table **table_ptr, uint32_t count,
701
bool should_lock, Table **write_lock_used);
704
uint32_t server_status;
705
uint32_t open_options;
706
uint32_t select_number; /**< number of select (used for EXPLAIN) */
707
/* variables.transaction_isolation is reset to this after each commit */
708
enum_tx_isolation session_tx_isolation;
709
enum_check_fields count_cuted_fields;
717
KILLED_NO_VALUE /* means none of the above states apply */
720
killed_state_t volatile _killed;
724
void setKilled(killed_state_t arg)
729
killed_state_t getKilled()
734
volatile killed_state_t *getKilledPtr() // Do not use this method, it is here for historical convience.
739
bool is_admin_connection;
740
bool some_tables_deleted;
744
Set to true if execution of the current compound statement
745
can not continue. In particular, disables activation of
746
CONTINUE or EXIT handlers of stored routines.
747
Reset in the end of processing of the current user request, in
748
@see reset_session_for_next_command().
752
Set by a storage engine to request the entire
753
transaction (that possibly spans multiple engines) to
754
rollback. Reset in ha_rollback.
756
bool transaction_rollback_request;
758
true if we are in a sub-statement and the current error can
759
not be safely recovered until we left the sub-statement mode.
760
In particular, disables activation of CONTINUE and EXIT
761
handlers inside sub-statements. E.g. if it is a deadlock
762
error and requires a transaction-wide rollback, this flag is
763
raised (traditionally, MySQL first has to close all the reads
764
via @see handler::ha_index_or_rnd_end() and only then perform
766
Reset to false when we leave the sub-statement mode.
768
bool is_fatal_sub_stmt_error;
769
/** for IS NULL => = last_insert_id() fix in remove_eq_conds() */
770
bool substitute_null_with_insert_id;
774
bool abort_on_warning;
775
bool tablespace_op; /**< This is true in DISCARD/IMPORT TABLESPACE */
778
bool got_warning; /**< Set on call to push_warning() */
779
bool no_warnings_for_error; /**< no warnings on call to my_error() */
780
/** set during loop of derived table processing */
781
bool derived_tables_processing;
783
bool doing_tablespace_operation(void)
785
return tablespace_op;
788
void setDoingTablespaceOperation(bool doing)
790
tablespace_op= doing;
794
/** Used by the sys_var class to store temporary values */
798
uint32_t uint32_t_value;
799
int32_t int32_t_value;
800
uint64_t uint64_t_value;
804
Character input stream consumed by the lexical analyser,
806
Note that since the parser is not re-entrant, we keep only one input
807
stream here. This member is valid only when executing code during parsing,
808
and may point to invalid memory after that.
810
Lex_input_stream *m_lip;
812
/** Place to store various things */
813
void *session_marker;
815
/** Keeps a copy of the previous table around in case we are just slamming on particular table */
819
Points to info-string that we show in SHOW PROCESSLIST
820
You are supposed to call Session_SET_PROC_INFO only if you have coded
821
a time-consuming piece that MySQL can get stuck in for a long time.
823
Set it using the session_proc_info(Session *thread, const char *message)
826
inline void set_proc_info(const char *info)
830
inline const char* get_proc_info() const
835
/** Sets this Session's current query ID */
836
inline void setQueryId(query_id_t in_query_id)
838
query_id= in_query_id;
841
/** Returns the current query ID */
842
query_id_t getQueryId() const
848
/** Sets this Session's warning query ID */
849
inline void setWarningQueryId(query_id_t in_query_id)
851
warn_query_id= in_query_id;
854
/** Returns the Session's warning query ID */
855
inline query_id_t getWarningQueryId() const
857
return warn_query_id;
860
/** Accessor method returning the session's ID. */
861
inline session_id_t getSessionId() const
866
/** Accessor method returning the server's ID. */
867
inline uint32_t getServerId() const
869
/* We return the global server ID. */
873
/** Returns the current transaction ID for the session's current statement */
874
inline my_xid getTransactionId()
876
return transaction.xid_state.xid.quick_get_my_xid();
879
1215
There is BUG#19630 where statement-based replication of stored
880
1216
functions/triggers with two auto_increment columns breaks.
881
1217
We however ensure that it works when there is 0 or 1 auto_increment
931
1274
auto_inc_intervals_forced.append(next_id, UINT64_MAX, 0);
934
Session(plugin::Client *client_arg, catalog::Instance::shared_ptr catalog);
1277
uint64_t limit_found_rows;
1278
uint64_t options; /* Bitmap of states */
1279
int64_t row_count_func; /* For the ROW_COUNT() function */
1280
ha_rows cuted_fields;
1283
number of rows we actually sent to the client, including "synthetic"
1286
ha_rows sent_row_count;
1289
number of rows we read, sent or not, including in create_sort_index()
1291
ha_rows examined_row_count;
1294
The set of those tables whose fields are referenced in all subqueries
1296
TODO: possibly this it is incorrect to have used tables in THD because
1297
with more than one subquery, it is not clear what does the field mean.
1299
table_map used_tables;
1300
USER_CONN *user_connect;
1301
const CHARSET_INFO *db_charset;
1303
FIXME: this, and some other variables like 'count_cuted_fields'
1304
maybe should be statement/cursor local, that is, moved to Statement
1305
class. With current implementation warnings produced in each prepared
1306
statement/cursor settle here.
1308
List <DRIZZLE_ERROR> warn_list;
1309
uint warn_count[(uint) DRIZZLE_ERROR::WARN_LEVEL_END];
1310
uint total_warn_count;
1311
Diagnostics_area main_da;
1314
Id of current query. Statement can be reused to execute several queries
1315
query_id is global in context of the whole MySQL server.
1316
ID is automatically generated from mutex-protected counter.
1317
It's used in handler code for various purposes: to check which columns
1318
from table are necessary for this select, to check if it's necessary to
1319
update auto-updatable fields (like auto_increment and timestamp).
1321
query_id_t query_id, warn_id;
1324
#ifdef ERROR_INJECT_SUPPORT
1325
ulong error_inject_value;
1327
/* Statement id is thread-wide. This counter is used to generate ids */
1328
ulong statement_id_counter;
1329
ulong rand_saved_seed1, rand_saved_seed2;
1331
Row counter, mainly for errors and warnings. Not increased in
1332
create_sort_index(); may differ from examined_row_count.
1335
pthread_t real_id; /* For debugging */
1336
my_thread_id thread_id;
1337
uint tmp_table, global_read_lock;
1338
uint server_status,open_options;
1339
enum enum_thread_type system_thread;
1340
uint32_t select_number; //number of select (used for EXPLAIN)
1341
/* variables.transaction_isolation is reset to this after each commit */
1342
enum_tx_isolation session_tx_isolation;
1343
enum_check_fields count_cuted_fields;
1345
DYNAMIC_ARRAY user_var_events; /* For user variables replication */
1346
MEM_ROOT *user_var_events_alloc; /* Allocate above array elements here */
1352
KILL_CONNECTION=ER_SERVER_SHUTDOWN,
1353
KILL_QUERY=ER_QUERY_INTERRUPTED,
1354
KILLED_NO_VALUE /* means neither of the states */
1356
killed_state volatile killed;
1358
/* scramble - random string sent to client on handshake */
1359
char scramble[SCRAMBLE_LENGTH+1];
1361
bool slave_thread, one_shot_set;
1362
/* tells if current statement should binlog row-based(1) or stmt-based(0) */
1363
bool current_stmt_binlog_row_based;
1364
bool some_tables_deleted;
1365
bool last_cuted_field;
1366
bool no_errors, password;
1368
Set to true if execution of the current compound statement
1369
can not continue. In particular, disables activation of
1370
CONTINUE or EXIT handlers of stored routines.
1371
Reset in the end of processing of the current user request, in
1372
@see mysql_reset_thd_for_next_command().
1374
bool is_fatal_error;
1376
Set by a storage engine to request the entire
1377
transaction (that possibly spans multiple engines) to
1378
rollback. Reset in ha_rollback.
1380
bool transaction_rollback_request;
1382
true if we are in a sub-statement and the current error can
1383
not be safely recovered until we left the sub-statement mode.
1384
In particular, disables activation of CONTINUE and EXIT
1385
handlers inside sub-statements. E.g. if it is a deadlock
1386
error and requires a transaction-wide rollback, this flag is
1387
raised (traditionally, MySQL first has to close all the reads
1388
via @see handler::ha_index_or_rnd_end() and only then perform
1390
Reset to false when we leave the sub-statement mode.
1392
bool is_fatal_sub_stmt_error;
1393
bool query_start_used, rand_used, time_zone_used;
1394
/* for IS NULL => = last_insert_id() fix in remove_eq_conds() */
1395
bool substitute_null_with_insert_id;
1396
bool in_lock_tables;
1398
True if a slave error. Causes the slave to stop. Not the same
1399
as the statement execution error (is_error()), since
1400
a statement may be expected to return an error, e.g. because
1401
it returned an error on master, and this is OK on the slave.
1403
bool is_slave_error;
1404
bool bootstrap, cleanup_done;
1406
/** is set if some thread specific value(s) used in a statement. */
1407
bool thread_specific_used;
1408
bool charset_is_system_charset, charset_is_collation_connection;
1409
bool charset_is_character_set_filesystem;
1410
bool enable_slow_log; /* enable slow log for current statement */
1411
bool abort_on_warning;
1412
bool got_warning; /* Set on call to push_warning() */
1413
bool no_warnings_for_error; /* no warnings on call to my_error() */
1414
/* set during loop of derived table processing */
1415
bool derived_tables_processing;
1416
bool tablespace_op; /* This is true in DISCARD/IMPORT TABLESPACE */
1419
If we do a purge of binary logs, log index info of the threads
1420
that are currently reading it needs to be adjusted. To do that
1421
each thread that is using LOG_INFO needs to adjust the pointer to it
1423
LOG_INFO* current_linfo;
1424
NET* slave_net; // network connection from slave -> m.
1425
/* Used by the sys_var class to store temporary values */
1431
uint64_t uint64_t_value;
1436
If true, mysql_bin_log::write(Log_event) call will not write events to
1437
binlog, and maintain 2 below variables instead (use
1438
mysql_bin_log.start_union_events to turn this on)
1442
If true, at least one mysql_bin_log::write(Log_event) call has been
1443
made after last mysql_bin_log.start_union_events() call.
1445
bool unioned_events;
1447
If true, at least one mysql_bin_log::write(Log_event e), where
1448
e.cache_stmt == true call has been made after last
1449
mysql_bin_log.start_union_events() call.
1451
bool unioned_events_trans;
1454
'queries' (actually SP statements) that run under inside this binlog
1455
union have thd->query_id >= first_query_id.
1457
query_id_t first_query_id;
1461
Character input stream consumed by the lexical analyser,
1462
used during parsing.
1463
Note that since the parser is not re-entrant, we keep only one input
1464
stream here. This member is valid only when executing code during parsing,
1465
and may point to invalid memory after that.
1467
Lex_input_stream *m_lip;
1474
Initialize memory roots necessary for query processing and (!)
1475
pre-allocate memory for it. We can't do that in THD constructor because
1476
there are use cases (acl_init, watcher threads,
1477
killing mysqld) where it's vital to not allocate excessive and not used
1478
memory. Note, that we still don't return error from init_for_queries():
1479
if preallocation fails, we should notice that at the first call to
1482
void init_for_queries();
1483
void change_user(void);
937
1484
void cleanup(void);
939
* Cleans up after query.
943
* This function is used to reset thread data to its default state.
945
* This function is not suitable for setting thread data to some
946
* non-default values, as there is only one replication thread, so
947
* different master threads may overwrite data of each other on
950
1485
void cleanup_after_query();
952
void awake(Session::killed_state_t state_to_set);
954
* Pulls thread-specific variables into Session state.
956
* Returns true most times, or false if there was a problem
957
* allocating resources for thread-specific storage.
959
* @TODO Kill this. It's not necessary once my_thr_init() is bye bye.
965
Initialize memory roots necessary for query processing and (!)
966
pre-allocate memory for it. We can't do that in Session constructor because
967
there are use cases where it's vital to not allocate excessive and not used
970
void prepareForQueries();
973
* Executes a single statement received from the
976
* Returns true if the statement was successful, or false
981
* For profiling to work, it must never be called recursively.
983
* In MySQL, this used to be the do_command() C function whic
984
* accepted a single parameter of the THD pointer.
986
bool executeStatement();
989
* Reads a query from packet and stores it.
991
* Returns true if query is read and allocated successfully,
992
* false otherwise. On a return of false, Session::fatal_error
995
* @note Used in COM_QUERY and COM_STMT_PREPARE.
997
* Sets the following Session variables:
1001
* @param The packet pointer to read from
1002
* @param The length of the query to read
1004
bool readAndStoreQuery(const char *in_packet, uint32_t in_packet_length);
1007
* Ends the current transaction and (maybe) begins the next.
1009
* Returns true if the transaction completed successfully,
1012
* @param Completion type
1014
bool endTransaction(enum enum_mysql_completiontype completion);
1015
bool endActiveTransaction();
1016
bool startTransaction(start_transaction_option_t opt= START_TRANS_NO_OPTIONS);
1017
void markTransactionForRollback(bool all);
1020
* Authenticates users, with error reporting.
1022
* Returns true on success, or false on failure.
1024
bool authenticate();
1029
* This will initialize the session and begin the command loop.
1034
* Schedule a session to be run on the default scheduler.
1036
static bool schedule(Session::shared_ptr&);
1038
static void unlink(session_id_t &session_id);
1039
static void unlink(Session::shared_ptr&);
1486
bool store_globals();
1487
void awake(THD::killed_state state_to_set);
1489
enum enum_binlog_query_type {
1491
The query can be logged row-based or statement-based
1496
The query has to be logged statement-based
1501
The query represents a change to a table in the "mysql"
1502
database and is currently mapped to ROW_QUERY_TYPE.
1508
int binlog_query(enum_binlog_query_type qtype,
1509
char const *query, ulong query_len,
1510
bool is_trans, bool suppress_use,
1511
THD::killed_state killed_err_arg= THD::KILLED_NO_VALUE);
1042
1514
For enter_cond() / exit_cond() to work the mutex must be got before
1043
1515
enter_cond(); this mutex is then released by exit_cond().
1044
1516
Usage must be: lock mutex; enter_cond(); your code; exit_cond().
1046
const char* enter_cond(boost::condition_variable_any &cond, boost::mutex &mutex, const char* msg);
1047
void exit_cond(const char* old_msg);
1049
type::Time::epoch_t query_start()
1051
return getCurrentTimestampEpoch();
1056
_end_timer= _start_timer= boost::posix_time::microsec_clock::universal_time();
1057
utime_after_lock= (_start_timer - _epoch).total_microseconds();
1060
void set_time(time_t t) // This is done by a sys_var, as long as user_time is set, we will use that for all references to time
1062
_user_time= boost::posix_time::from_time_t(t);
1065
void set_time_after_lock()
1067
boost::posix_time::ptime mytime(boost::posix_time::microsec_clock::universal_time());
1068
utime_after_lock= (mytime - _epoch).total_microseconds();
1071
void set_end_timer()
1073
_end_timer= boost::posix_time::microsec_clock::universal_time();
1074
status_var.execution_time_nsec+=(_end_timer - _start_timer).total_microseconds();
1077
uint64_t getElapsedTime() const
1079
return (_end_timer - _start_timer).total_microseconds();
1083
* Returns the current micro-timestamp
1085
type::Time::epoch_t getCurrentTimestamp(bool actual= true) const
1087
type::Time::epoch_t t_mark;
1518
inline const char* enter_cond(pthread_cond_t *cond, pthread_mutex_t* mutex,
1521
const char* old_msg = get_proc_info();
1522
safe_mutex_assert_owner(mutex);
1523
mysys_var->current_mutex = mutex;
1524
mysys_var->current_cond = cond;
1525
thd_proc_info(this, msg);
1528
inline void exit_cond(const char* old_msg)
1531
Putting the mutex unlock in exit_cond() ensures that
1532
mysys_var->current_mutex is always unlocked _before_ mysys_var->mutex is
1533
locked (if that would not be the case, you'll get a deadlock if someone
1534
does a THD::awake() on you).
1536
pthread_mutex_unlock(mysys_var->current_mutex);
1537
pthread_mutex_lock(&mysys_var->mutex);
1538
mysys_var->current_mutex = 0;
1539
mysys_var->current_cond = 0;
1540
thd_proc_info(this, old_msg);
1541
pthread_mutex_unlock(&mysys_var->mutex);
1543
inline time_t query_start() { query_start_used=1; return start_time; }
1544
inline void set_time()
1091
boost::posix_time::ptime mytime(boost::posix_time::microsec_clock::universal_time());
1092
t_mark= (mytime - _epoch).total_microseconds();
1548
start_time= user_time;
1549
start_utime= utime_after_lock= my_micro_time();
1096
t_mark= (_end_timer - _epoch).total_microseconds();
1102
// We may need to set user on this
1103
type::Time::epoch_t getCurrentTimestampEpoch() const
1105
if (not _user_time.is_not_a_date_time())
1106
return (_user_time - _epoch).total_seconds();
1108
return (_start_timer - _epoch).total_seconds();
1111
type::Time::epoch_t getCurrentTimestampEpoch(type::Time::usec_t &fraction_arg) const
1113
if (not _user_time.is_not_a_date_time())
1116
return (_user_time - _epoch).total_seconds();
1119
fraction_arg= _start_timer.time_of_day().fractional_seconds() % 1000000;
1120
return (_start_timer - _epoch).total_seconds();
1123
uint64_t found_rows(void) const
1552
start_utime= utime_after_lock= my_micro_time_and_time(&start_time);
1554
inline void set_current_time() { start_time= my_time(MY_WME); }
1555
inline void set_time(time_t t)
1557
start_time= user_time= t;
1558
start_utime= utime_after_lock= my_micro_time();
1560
void set_time_after_lock() { utime_after_lock= my_micro_time(); }
1561
uint64_t current_utime() { return my_micro_time(); }
1562
inline uint64_t found_rows(void)
1125
1564
return limit_found_rows;
1128
/** Returns whether the session is currently inside a transaction */
1129
bool inTransaction() const
1566
inline bool active_transaction()
1131
1568
return server_status & SERVER_STATUS_IN_TRANS;
1570
inline bool fill_derived_tables()
1572
return !lex->only_view_structure();
1574
inline void* trans_alloc(unsigned int size)
1576
return alloc_root(&transaction.mem_root,size);
1134
1579
LEX_STRING *make_lex_string(LEX_STRING *lex_str,
1135
1580
const char* str, uint32_t length,
1136
1581
bool allocate_lex_string);
1138
LEX_STRING *make_lex_string(LEX_STRING *lex_str,
1139
const std::string &str,
1140
bool allocate_lex_string);
1583
bool convert_string(LEX_STRING *to, const CHARSET_INFO * const to_cs,
1584
const char *from, uint32_t from_length,
1585
const CHARSET_INFO * const from_cs);
1587
bool convert_string(String *s, const CHARSET_INFO * const from_cs, const CHARSET_INFO * const to_cs);
1589
void add_changed_table(Table *table);
1590
void add_changed_table(const char *key, long key_length);
1591
CHANGED_TableList * changed_table_dup(const char *key, long key_length);
1142
1592
int send_explain_fields(select_result *result);
1145
1594
Clear the current error, if any.
1146
1595
We do not clear is_fatal_error or is_fatal_sub_stmt_error since we
1461
1814
- for prepared queries, only to allocate runtime data. The parsed
1462
1815
tree itself is reused between executions and thus is stored elsewhere.
1464
memory::Root main_mem_root;
1467
* Marks all tables in the list which were used by current substatement
1468
* as free for reuse.
1470
* @param Head of the list of tables
1474
* The reason we reset query_id is that it's not enough to just test
1475
* if table->query_id != session->query_id to know if a table is in use.
1479
* SELECT f1_that_uses_t1() FROM t1;
1481
* In f1_that_uses_t1() we will see one instance of t1 where query_id is
1482
* set to query_id of original query.
1484
void mark_used_tables_as_free_for_reuse(Table *table);
1488
/** A short cut for session->main_da.set_ok_status(). */
1489
inline void my_ok(ha_rows affected_rows= 0, ha_rows found_rows_arg= 0,
1490
uint64_t passed_id= 0, const char *message= NULL)
1492
main_da.set_ok_status(this, affected_rows, found_rows_arg, passed_id, message);
1496
/** A short cut for session->main_da.set_eof_status(). */
1498
inline void my_eof()
1500
main_da.set_eof_status(this);
1503
/* Some inline functions for more speed */
1505
inline bool add_item_to_list(Item *item)
1507
return lex->current_select->add_item_to_list(this, item);
1510
inline bool add_value_to_list(Item *value)
1512
return lex->value_list.push_back(value);
1515
inline bool add_order_to_list(Item *item, bool asc)
1517
return lex->current_select->add_order_to_list(this, item, asc);
1520
inline bool add_group_to_list(Item *item, bool asc)
1522
return lex->current_select->add_group_to_list(this, item, asc);
1524
void refresh_status();
1525
user_var_entry *getVariable(LEX_STRING &name, bool create_if_not_exists);
1526
user_var_entry *getVariable(const std::string &name, bool create_if_not_exists);
1527
void setVariable(const std::string &name, const std::string &value);
1530
* Closes all tables used by the current substatement, or all tables
1531
* used by this thread if we are on the upper level.
1533
void close_thread_tables();
1534
void close_old_data_files(bool morph_locks= false,
1535
bool send_refresh= false);
1536
void close_open_tables();
1537
void close_data_files_and_morph_locks(const identifier::Table &identifier);
1540
bool free_cached_table(boost::mutex::scoped_lock &scopedLock);
1545
* Prepares statement for reopening of tables and recalculation of set of
1548
* @param Pointer to a pointer to a list of tables which we were trying to open and lock
1550
void close_tables_for_reopen(TableList **tables);
1554
* Open all tables in list, locks them (all, including derived)
1556
* @param Pointer to a list of tables for open & locking
1565
* The lock will automaticaly be freed by close_thread_tables()
1567
bool openTablesLock(TableList *tables);
1569
int open_tables_from_list(TableList **start, uint32_t *counter, uint32_t flags= 0);
1571
Table *openTableLock(TableList *table_list, thr_lock_type lock_type);
1572
Table *openTable(TableList *table_list, bool *refresh, uint32_t flags= 0);
1574
void unlink_open_table(Table *find);
1575
void drop_open_table(Table *table, const identifier::Table &identifier);
1576
void close_cached_table(Table *table);
1578
/* Create a lock in the cache */
1579
table::Placeholder *table_cache_insert_placeholder(const identifier::Table &identifier);
1580
bool lock_table_name_if_not_cached(const identifier::Table &identifier, Table **table);
1583
session::TableMessages _table_message_cache;
1586
session::TableMessages &getMessageCache()
1588
return _table_message_cache;
1591
/* Reopen operations */
1592
bool reopen_tables();
1593
bool close_cached_tables(TableList *tables, bool wait_for_refresh, bool wait_for_placeholders);
1595
void wait_for_condition(boost::mutex &mutex, boost::condition_variable_any &cond);
1596
int setup_conds(TableList *leaves, COND **conds);
1597
int lock_tables(TableList *tables, uint32_t count, bool *need_reopen);
1599
drizzled::util::Storable *getProperty(const std::string &arg)
1601
return life_properties.getProperty(arg);
1605
bool setProperty(const std::string &arg, T *value)
1607
life_properties.setProperty(arg, value);
1613
Return the default storage engine
1615
@param getDefaultStorageEngine()
1618
pointer to plugin::StorageEngine
1620
plugin::StorageEngine *getDefaultStorageEngine()
1622
if (variables.storage_engine)
1623
return variables.storage_engine;
1624
return global_system_variables.storage_engine;
1627
void get_xid(DrizzleXid *xid); // Innodb only
1629
table::Singular *getInstanceTable();
1630
table::Singular *getInstanceTable(List<CreateField> &field_list);
1635
if (getrusage(RUSAGE_THREAD, &usage))
1645
void setUsage(bool arg)
1650
const struct rusage &getUsage()
1655
catalog::Instance::const_reference catalog() const
1657
return *(_catalog.get());
1660
catalog::Instance::reference catalog()
1662
return *(_catalog.get());
1666
catalog::Instance::shared_ptr _catalog;
1668
// This lives throughout the life of Session
1670
session::PropertyMap life_properties;
1671
std::vector<table::Singular *> temporary_shares;
1672
struct rusage usage;
1817
MEM_ROOT main_mem_root;
1821
/** A short cut for thd->main_da.set_ok_status(). */
1824
my_ok(THD *thd, ha_rows affected_rows= 0, uint64_t id= 0,
1825
const char *message= NULL)
1827
thd->main_da.set_ok_status(thd, affected_rows, id, message);
1831
/** A short cut for thd->main_da.set_eof_status(). */
1836
thd->main_da.set_eof_status(thd);
1839
#define tmp_disable_binlog(A) \
1840
{uint64_t tmp_disable_binlog__save_options= (A)->options; \
1841
(A)->options&= ~OPTION_BIN_LOG
1843
#define reenable_binlog(A) (A)->options= tmp_disable_binlog__save_options;}
1847
Used to hold information about file and file structure in exchange
1848
via non-DB file (...INTO OUTFILE..., ...LOAD DATA...)
1849
XXX: We never call destructor for objects of this class.
1852
class sql_exchange :public Sql_alloc
1855
enum enum_filetype filetype; /* load XML, Added by Arnold & Erik */
1857
String *field_term,*enclosed,*line_term,*line_start,*escaped;
1861
const CHARSET_INFO *cs;
1862
sql_exchange(char *name, bool dumpfile_flag,
1863
enum_filetype filetype_arg= FILETYPE_CSV);
1866
#include "log_event.h"
1869
This is used to get result from a select
1874
class select_result :public Sql_alloc {
1877
SELECT_LEX_UNIT *unit;
1880
virtual ~select_result() {};
1881
virtual int prepare(List<Item> &list __attribute__((unused)),
1887
virtual int prepare2(void) { return 0; }
1889
Because of peculiarities of prepared statements protocol
1890
we need to know number of columns in the result set (if
1891
there is a result set) apart from sending columns metadata.
1893
virtual uint32_t field_count(List<Item> &fields) const
1894
{ return fields.elements; }
1895
virtual bool send_fields(List<Item> &list, uint32_t flags)=0;
1896
virtual bool send_data(List<Item> &items)=0;
1897
virtual bool initialize_tables (JOIN __attribute__((unused)) *join=0)
1899
virtual void send_error(uint32_t errcode,const char *err);
1900
virtual bool send_eof()=0;
1902
Check if this query returns a result set and therefore is allowed in
1903
cursors and set an error message if it is not the case.
1905
@retval false success
1906
@retval true error, an error message is set
1908
virtual bool check_simple_select() const;
1909
virtual void abort() {}
1911
Cleanup instance of this class for next execution of a prepared
1912
statement/stored procedure.
1914
virtual void cleanup();
1915
void set_thd(THD *thd_arg) { thd= thd_arg; }
1916
void begin_dataset() {}
1921
Base class for select_result descendands which intercept and
1922
transform result set rows. As the rows are not sent to the client,
1923
sending of result set metadata should be suppressed as well.
1926
class select_result_interceptor: public select_result
1929
select_result_interceptor() {} /* Remove gcc warning */
1930
uint32_t field_count(List<Item> &fields __attribute__((unused))) const
1932
bool send_fields(List<Item> &fields __attribute__((unused)),
1933
uint32_t flag __attribute__((unused))) { return false; }
1937
class select_send :public select_result {
1939
True if we have sent result set metadata to the client.
1940
In this case the client always expects us to end the result
1941
set with an eof or error packet
1943
bool is_result_set_started;
1945
select_send() :is_result_set_started(false) {}
1946
bool send_fields(List<Item> &list, uint32_t flags);
1947
bool send_data(List<Item> &items);
1949
virtual bool check_simple_select() const { return false; }
1951
virtual void cleanup();
1955
class select_to_file :public select_result_interceptor {
1957
sql_exchange *exchange;
1961
char path[FN_REFLEN];
1964
select_to_file(sql_exchange *ex) :exchange(ex), file(-1),row_count(0L)
1967
void send_error(uint32_t errcode,const char *err);
1675
1973
#define ESCAPE_CHARS "ntrb0ZN" // keep synchronous with READ_INFO::unescape
1977
List of all possible characters of a numeric value text representation.
1979
#define NUMERIC_CHARS ".0123456789e+-"
1982
class select_export :public select_to_file {
1983
uint32_t field_term_length;
1984
int field_sep_char,escape_char,line_sep_char;
1985
int field_term_char; // first char of FIELDS TERMINATED BY or MAX_INT
1987
The is_ambiguous_field_sep field is true if a value of the field_sep_char
1988
field is one of the 'n', 't', 'r' etc characters
1989
(see the READ_INFO::unescape method and the ESCAPE_CHARS constant value).
1991
bool is_ambiguous_field_sep;
1993
The is_ambiguous_field_term is true if field_sep_char contains the first
1994
char of the FIELDS TERMINATED BY (ENCLOSED BY is empty), and items can
1995
contain this character.
1997
bool is_ambiguous_field_term;
1999
The is_unsafe_field_sep field is true if a value of the field_sep_char
2000
field is one of the '0'..'9', '+', '-', '.' and 'e' characters
2001
(see the NUMERIC_CHARS constant value).
2003
bool is_unsafe_field_sep;
2004
bool fixed_row_size;
2006
select_export(sql_exchange *ex) :select_to_file(ex) {}
2008
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2009
bool send_data(List<Item> &items);
2013
class select_dump :public select_to_file {
2015
select_dump(sql_exchange *ex) :select_to_file(ex) {}
2016
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2017
bool send_data(List<Item> &items);
2021
class select_insert :public select_result_interceptor {
2023
TableList *table_list;
2026
uint64_t autoinc_value_of_last_inserted_row; // autogenerated or not
2028
bool insert_into_view;
2029
select_insert(TableList *table_list_par,
2030
Table *table_par, List<Item> *fields_par,
2031
List<Item> *update_fields, List<Item> *update_values,
2032
enum_duplicates duplic, bool ignore);
2034
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2035
virtual int prepare2(void);
2036
bool send_data(List<Item> &items);
2037
virtual void store_values(List<Item> &values);
2038
virtual bool can_rollback_data() { return 0; }
2039
void send_error(uint32_t errcode,const char *err);
2042
/* not implemented: select_insert is never re-used in prepared statements */
2047
class select_create: public select_insert {
2049
TableList *create_table;
2050
HA_CREATE_INFO *create_info;
2051
TableList *select_tables;
2052
Alter_info *alter_info;
2054
/* lock data for tmp table */
2055
DRIZZLE_LOCK *m_lock;
2056
/* m_lock or thd->extra_lock */
2057
DRIZZLE_LOCK **m_plock;
2059
select_create (TableList *table_arg,
2060
HA_CREATE_INFO *create_info_par,
2061
Alter_info *alter_info_arg,
2062
List<Item> &select_fields,enum_duplicates duplic, bool ignore,
2063
TableList *select_tables_arg)
2064
:select_insert (NULL, NULL, &select_fields, 0, 0, duplic, ignore),
2065
create_table(table_arg),
2066
create_info(create_info_par),
2067
select_tables(select_tables_arg),
2068
alter_info(alter_info_arg),
2071
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2073
void binlog_show_create_table(Table **tables, uint32_t count);
2074
void store_values(List<Item> &values);
2075
void send_error(uint32_t errcode,const char *err);
2078
virtual bool can_rollback_data() { return 1; }
2080
// Needed for access from local class MY_HOOKS in prepare(), since thd is proteted.
2081
const THD *get_thd(void) { return thd; }
2082
const HA_CREATE_INFO *get_create_info() { return create_info; };
2083
int prepare2(void) { return 0; }
2086
#include <storage/myisam/myisam.h>
2089
Param to create temporary tables when doing SELECT:s
2091
This structure is copied using memcpy as a part of JOIN.
2094
class TMP_TABLE_PARAM :public Sql_alloc
2097
/* Prevent use of these (not safe because of lists and copy_field) */
2098
TMP_TABLE_PARAM(const TMP_TABLE_PARAM &);
2099
void operator=(TMP_TABLE_PARAM &);
2102
List<Item> copy_funcs;
2103
List<Item> save_copy_funcs;
2104
Copy_field *copy_field, *copy_field_end;
2105
Copy_field *save_copy_field, *save_copy_field_end;
2106
unsigned char *group_buff;
2107
Item **items_to_copy; /* Fields in tmp table */
2108
MI_COLUMNDEF *recinfo,*start_recinfo;
2110
ha_rows end_write_records;
2111
uint field_count,sum_func_count,func_count;
2112
uint32_t hidden_field_count;
2113
uint group_parts,group_length,group_null_parts;
2115
bool using_indirect_summary_function;
2116
/* If >0 convert all blob fields to varchar(convert_blob_length) */
2117
uint32_t convert_blob_length;
2118
const CHARSET_INFO *table_charset;
2121
True if GROUP BY and its aggregate functions are already computed
2122
by a table access method (e.g. by loose index scan). In this case
2123
query execution should not perform aggregation and should treat
2124
aggregate functions as normal functions.
2126
bool precomputed_group_by;
2127
bool force_copy_fields;
2129
If true, create_tmp_field called from create_tmp_table will convert
2130
all BIT fields to 64-bit longs. This is a workaround the limitation
2131
that MEMORY tables cannot index BIT columns.
2133
bool bit_fields_as_long;
2136
:copy_field(0), group_parts(0),
2137
group_length(0), group_null_parts(0), convert_blob_length(0),
2138
schema_table(0), precomputed_group_by(0), force_copy_fields(0),
2139
bit_fields_as_long(0)
2146
inline void cleanup(void)
2148
if (copy_field) /* Fix for Intel compiler */
2150
delete [] copy_field;
2151
save_copy_field= copy_field= 0;
2156
class select_union :public select_result_interceptor
2158
TMP_TABLE_PARAM tmp_table_param;
2162
select_union() :table(0) {}
2163
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2164
bool send_data(List<Item> &items);
2168
bool create_result_table(THD *thd, List<Item> *column_types,
2169
bool is_distinct, uint64_t options,
2170
const char *alias, bool bit_fields_as_long);
2173
/* Base subselect interface class */
2174
class select_subselect :public select_result_interceptor
2177
Item_subselect *item;
2179
select_subselect(Item_subselect *item);
2180
bool send_data(List<Item> &items)=0;
2181
bool send_eof() { return 0; };
2184
/* Single value subselect interface class */
2185
class select_singlerow_subselect :public select_subselect
2188
select_singlerow_subselect(Item_subselect *item_arg)
2189
:select_subselect(item_arg)
2191
bool send_data(List<Item> &items);
2194
/* used in independent ALL/ANY optimisation */
2195
class select_max_min_finder_subselect :public select_subselect
2198
bool (select_max_min_finder_subselect::*op)();
2201
select_max_min_finder_subselect(Item_subselect *item_arg, bool mx)
2202
:select_subselect(item_arg), cache(0), fmax(mx)
2205
bool send_data(List<Item> &items);
2212
/* EXISTS subselect interface class */
2213
class select_exists_subselect :public select_subselect
2216
select_exists_subselect(Item_subselect *item_arg)
2217
:select_subselect(item_arg){}
2218
bool send_data(List<Item> &items);
2221
/* Structs used when sorting */
2223
typedef struct st_sort_field {
2224
Field *field; /* Field to sort */
2225
Item *item; /* Item if not sorting fields */
2226
uint length; /* Length of sort field */
2227
uint32_t suffix_length; /* Length suffix (0-4) */
2228
Item_result result_type; /* Type of item */
2229
bool reverse; /* if descending sort */
2230
bool need_strxnfrm; /* If we have to use strxnfrm() */
2234
typedef struct st_sort_buffer {
2235
uint32_t index; /* 0 or 1 */
2236
uint32_t sort_orders;
2237
uint32_t change_pos; /* If sort-fields changed */
2239
SORT_FIELD *sortorder;
2242
/* Structure for db & table in sql_yacc */
2244
class Table_ident :public Sql_alloc
2249
SELECT_LEX_UNIT *sel;
2250
inline Table_ident(THD *thd, LEX_STRING db_arg, LEX_STRING table_arg,
2252
:table(table_arg), sel((SELECT_LEX_UNIT *)0)
2254
if (!force && (thd->client_capabilities & CLIENT_NO_SCHEMA))
2259
inline Table_ident(LEX_STRING table_arg)
2260
:table(table_arg), sel((SELECT_LEX_UNIT *)0)
2265
This constructor is used only for the case when we create a derived
2266
table. A derived table has no name and doesn't belong to any database.
2267
Later, if there was an alias specified for the table, it will be set
2268
by add_table_to_list.
2270
inline Table_ident(SELECT_LEX_UNIT *s) : sel(s)
2272
/* We must have a table name here as this is used with add_table_to_list */
2273
db.str= empty_c_string; /* a subject to casedn_str */
2275
table.str= internal_table_name;
2278
bool is_derived_table() const { return test(sel); }
2279
inline void change_db(char *db_name)
2281
db.str= db_name; db.length= (uint) strlen(db_name);
2285
// this is needed for user_vars hash
2286
class user_var_entry
2289
user_var_entry() {} /* Remove gcc warning */
2293
query_id_t update_query_id, used_query_id;
2297
double val_real(bool *null_value);
2298
int64_t val_int(bool *null_value) const;
2299
String *val_str(bool *null_value, String *str, uint32_t decimals);
2300
my_decimal *val_decimal(bool *null_value, my_decimal *result);
2301
DTCollation collation;
2305
Unique -- class for unique (removing of duplicates).
2306
Puts all values to the TREE. If the tree becomes too big,
2307
it's dumped to the file. User can request sorted values, or
2308
just iterate through them. In the last case tree merging is performed in
2309
memory simultaneously with iteration, so it should be ~2-3x faster.
2312
class Unique :public Sql_alloc
2314
DYNAMIC_ARRAY file_ptrs;
2316
uint64_t max_in_memory_size;
2319
unsigned char *record_pointers;
2325
Unique(qsort_cmp2 comp_func, void *comp_func_fixed_arg,
2326
uint32_t size_arg, uint64_t max_in_memory_size_arg);
2328
ulong elements_in_tree() { return tree.elements_in_tree; }
2329
inline bool unique_add(void *ptr)
2331
if (tree.elements_in_tree > max_elements && flush())
2333
return(!tree_insert(&tree, ptr, 0, tree.custom_arg));
2336
bool get(Table *table);
2337
static double get_use_cost(uint32_t *buffer, uint32_t nkeys, uint32_t key_size,
2338
uint64_t max_in_memory_size);
2339
inline static int get_cost_calc_buff_size(ulong nkeys, uint32_t key_size,
2340
uint64_t max_in_memory_size)
2342
register uint64_t max_elems_in_tree=
2343
(1 + max_in_memory_size / ALIGN_SIZE(sizeof(TREE_ELEMENT)+key_size));
2344
return (int) (sizeof(uint)*(1 + nkeys/max_elems_in_tree));
2348
bool walk(tree_walk_action action, void *walk_action_arg);
2350
friend int unique_write_to_file(unsigned char* key, element_count count, Unique *unique);
2351
friend int unique_write_to_ptrs(unsigned char* key, element_count count, Unique *unique);
2355
class multi_delete :public select_result_interceptor
2357
TableList *delete_tables, *table_being_deleted;
2359
ha_rows deleted, found;
2360
uint32_t num_of_tables;
2363
/* True if at least one table we delete from is transactional */
2364
bool transactional_tables;
2365
/* True if at least one table we delete from is not transactional */
2367
bool delete_while_scanning;
2369
error handling (rollback and binlogging) can happen in send_eof()
2370
so that afterward send_error() needs to find out that.
2375
multi_delete(TableList *dt, uint32_t num_of_tables);
2377
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2378
bool send_data(List<Item> &items);
2379
bool initialize_tables (JOIN *join);
2380
void send_error(uint32_t errcode,const char *err);
2383
virtual void abort();
2387
class multi_update :public select_result_interceptor
2389
TableList *all_tables; /* query/update command tables */
2390
TableList *leaves; /* list of leves of join table tree */
2391
TableList *update_tables, *table_being_updated;
2392
Table **tmp_tables, *main_table, *table_to_update;
2393
TMP_TABLE_PARAM *tmp_table_param;
2394
ha_rows updated, found;
2395
List <Item> *fields, *values;
2396
List <Item> **fields_for_table, **values_for_table;
2397
uint32_t table_count;
2399
List of tables referenced in the CHECK OPTION condition of
2400
the updated view excluding the updated table.
2402
List <Table> unupdated_check_opt_tables;
2403
Copy_field *copy_field;
2404
enum enum_duplicates handle_duplicates;
2405
bool do_update, trans_safe;
2406
/* True if the update operation has made a change in a transactional table */
2407
bool transactional_tables;
2410
error handling (rollback and binlogging) can happen in send_eof()
2411
so that afterward send_error() needs to find out that.
2416
multi_update(TableList *ut, TableList *leaves_list,
2417
List<Item> *fields, List<Item> *values,
2418
enum_duplicates handle_duplicates, bool ignore);
2420
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2421
bool send_data(List<Item> &items);
2422
bool initialize_tables (JOIN *join);
2423
void send_error(uint32_t errcode,const char *err);
2426
virtual void abort();
2429
class my_var : public Sql_alloc {
2434
enum_field_types type;
2435
my_var (LEX_STRING& j, bool i, uint32_t o, enum_field_types t)
2436
:s(j), local(i), offset(o), type(t)
2441
class select_dumpvar :public select_result_interceptor {
2444
List<my_var> var_list;
2445
select_dumpvar() { var_list.empty(); row_count= 0;}
2446
~select_dumpvar() {}
2447
int prepare(List<Item> &list, SELECT_LEX_UNIT *u);
2448
bool send_data(List<Item> &items);
2450
virtual bool check_simple_select() const;
1677
2454
/* Bits in sql_command_flags */
1679
enum sql_command_flag_bits
1681
CF_BIT_CHANGES_DATA,
1682
CF_BIT_HAS_ROW_COUNT,
1683
CF_BIT_STATUS_COMMAND,
1684
CF_BIT_SHOW_TABLE_COMMAND,
1685
CF_BIT_WRITE_LOGS_COMMAND,
1689
static const std::bitset<CF_BIT_SIZE> CF_CHANGES_DATA(1 << CF_BIT_CHANGES_DATA);
1690
static const std::bitset<CF_BIT_SIZE> CF_HAS_ROW_COUNT(1 << CF_BIT_HAS_ROW_COUNT);
1691
static const std::bitset<CF_BIT_SIZE> CF_STATUS_COMMAND(1 << CF_BIT_STATUS_COMMAND);
1692
static const std::bitset<CF_BIT_SIZE> CF_SHOW_TABLE_COMMAND(1 << CF_BIT_SHOW_TABLE_COMMAND);
1693
static const std::bitset<CF_BIT_SIZE> CF_WRITE_LOGS_COMMAND(1 << CF_BIT_WRITE_LOGS_COMMAND);
1696
const std::string &type(drizzled::Session::global_read_lock_t type);
1697
size_t max_string_length(drizzled::Session::global_read_lock_t type);
1699
} /* namespace display */
1701
} /* namespace drizzled */
1703
#endif /* DRIZZLED_SESSION_H */
2456
#define CF_CHANGES_DATA 1
2457
#define CF_HAS_ROW_COUNT 2
2458
#define CF_STATUS_COMMAND 4
2459
#define CF_SHOW_TABLE_COMMAND 8
2460
#define CF_WRITE_LOGS_COMMAND 16
2462
/* Functions in sql_class.cc */
2464
void add_to_status(STATUS_VAR *to_var, STATUS_VAR *from_var);
2466
void add_diff_to_status(STATUS_VAR *to_var, STATUS_VAR *from_var,
2467
STATUS_VAR *dec_var);
2469
#endif /* DRIZZLE_SERVER */