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/***************************************************************************
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Delete multiple tables from join
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***************************************************************************/
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extern "C" int refpos_order_cmp(void* arg, const void *a,const void *b)
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handler *file= (handler*)arg;
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return file->cmp_ref((const unsigned char*)a, (const unsigned char*)b);
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make delete specific preparation and checks after opening tables
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mysql_multi_delete_prepare()
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session thread handler
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int mysql_multi_delete_prepare(Session *session)
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LEX *lex= session->lex;
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TableList *aux_tables= (TableList *)lex->auxiliary_table_list.first;
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TableList *target_tbl;
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setup_tables() need for VIEWs. JOIN::prepare() will not do it second
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lex->query_tables also point on local list of DELETE Select_Lex
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if (setup_tables_and_check_access(session, &session->lex->select_lex.context,
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&session->lex->select_lex.top_join_list,
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&lex->select_lex.leaf_tables, false))
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Multi-delete can't be constructed over-union => we always have
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single SELECT on top and have to check underlying SELECTs of it
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lex->select_lex.exclude_from_table_unique_test= true;
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/* Fix tables-to-be-deleted-from list to point at opened tables */
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for (target_tbl= (TableList*) aux_tables;
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target_tbl= target_tbl->next_local)
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target_tbl->table= target_tbl->correspondent_table->table;
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assert(target_tbl->table);
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Check that table from which we delete is not used somewhere
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inside subqueries/view.
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TableList *duplicate;
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if ((duplicate= unique_table(session, target_tbl->correspondent_table,
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lex->query_tables, 0)))
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my_error(ER_UPDATE_TABLE_USED, MYF(0), target_tbl->correspondent_table->alias);
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multi_delete::multi_delete(TableList *dt, uint32_t num_of_tables_arg)
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: delete_tables(dt), deleted(0), found(0),
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num_of_tables(num_of_tables_arg), error(0),
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do_delete(0), transactional_tables(0), normal_tables(0), error_handled(0)
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tempfiles= (Unique **) sql_calloc(sizeof(Unique *) * num_of_tables);
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multi_delete::prepare(List<Item> &, Select_Lex_Unit *u)
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session->set_proc_info("deleting from main table");
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multi_delete::initialize_tables(JOIN *join)
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Unique **tempfiles_ptr;
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if ((session->options & OPTION_SAFE_UPDATES) && error_if_full_join(join))
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table_map tables_to_delete_from=0;
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for (walk= delete_tables; walk; walk= walk->next_local)
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tables_to_delete_from|= walk->table->map;
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delete_while_scanning= 1;
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for (JoinTable *tab=join->join_tab, *end=join->join_tab+join->tables;
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if (tab->table->map & tables_to_delete_from)
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/* We are going to delete from this table */
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Table *tbl=walk->table=tab->table;
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walk= walk->next_local;
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/* Don't use KEYREAD optimization on this table */
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/* Don't use record cache */
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tbl->covering_keys.reset();
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if (tbl->file->has_transactions())
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transactional_tables= 1;
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tbl->prepare_for_position();
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tbl->mark_columns_needed_for_delete();
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else if ((tab->type != JT_SYSTEM && tab->type != JT_CONST) &&
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walk == delete_tables)
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We are not deleting from the table we are scanning. In this
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case send_data() shouldn't delete any rows a we may touch
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the rows in the deleted table many times
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delete_while_scanning= 0;
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tempfiles_ptr= tempfiles;
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if (delete_while_scanning)
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table_being_deleted= delete_tables;
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walk= walk->next_local;
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for (;walk ;walk= walk->next_local)
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Table *table=walk->table;
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*tempfiles_ptr++= new Unique (refpos_order_cmp,
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(void *) table->file,
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table->file->ref_length,
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current_session->variables.sortbuff_size);
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return(session->is_fatal_error != 0);
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multi_delete::~multi_delete()
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for (table_being_deleted= delete_tables;
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table_being_deleted= table_being_deleted->next_local)
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Table *table= table_being_deleted->table;
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for (uint32_t counter= 0; counter < num_of_tables; counter++)
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if (tempfiles[counter])
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delete tempfiles[counter];
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bool multi_delete::send_data(List<Item> &)
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int secure_counter= delete_while_scanning ? -1 : 0;
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TableList *del_table;
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for (del_table= delete_tables;
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del_table= del_table->next_local, secure_counter++)
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Table *table= del_table->table;
574
/* Check if we are using outer join and we didn't find the row */
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if (table->status & (STATUS_NULL_ROW | STATUS_DELETED))
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table->file->position(table->record[0]);
581
if (secure_counter < 0)
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/* We are scanning the current table */
584
assert(del_table == table_being_deleted);
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table->status|= STATUS_DELETED;
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if (!(error=table->file->ha_delete_row(table->record[0])))
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if (!table->file->has_transactions())
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session->transaction.stmt.modified_non_trans_table= true;
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table->file->print_error(error,MYF(0));
600
error=tempfiles[secure_counter]->unique_add((char*) table->file->ref);
603
error= 1; // Fatal error
612
void multi_delete::send_error(uint32_t errcode,const char *err)
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/* First send error what ever it is ... */
617
my_message(errcode, err, MYF(0));
623
void multi_delete::abort()
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/* the error was handled or nothing deleted and no side effects return */
629
(!session->transaction.stmt.modified_non_trans_table && !deleted))
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If rows from the first table only has been deleted and it is
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transactional, just do rollback.
635
The same if all tables are transactional, regardless of where we are.
636
In all other cases do attempt deletes ...
638
if (do_delete && normal_tables &&
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(table_being_deleted != delete_tables ||
640
!table_being_deleted->table->file->has_transactions()))
643
We have to execute the recorded do_deletes() and write info into the
648
assert(error_handled);
652
if (session->transaction.stmt.modified_non_trans_table)
654
session->transaction.all.modified_non_trans_table= true;
662
Do delete from other tables.
668
int multi_delete::do_deletes()
670
int local_error= 0, counter= 0, tmp_error;
675
do_delete= 0; // Mark called
679
table_being_deleted= (delete_while_scanning ? delete_tables->next_local :
682
for (; table_being_deleted;
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table_being_deleted= table_being_deleted->next_local, counter++)
685
ha_rows last_deleted= deleted;
686
Table *table = table_being_deleted->table;
687
if (tempfiles[counter]->get(table))
694
init_read_record(&info,session,table,NULL,0,1);
696
Ignore any rows not found in reference tables as they may already have
697
been deleted by foreign key handling
699
info.ignore_not_found_rows= 1;
700
will_batch= !table->file->start_bulk_delete();
701
while (!(local_error=info.read_record(&info)) && !session->killed)
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if ((local_error=table->file->ha_delete_row(table->record[0])))
705
table->file->print_error(local_error,MYF(0));
710
if (will_batch && (tmp_error= table->file->end_bulk_delete()))
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local_error= tmp_error;
715
table->file->print_error(local_error,MYF(0));
718
if (last_deleted != deleted && !table->file->has_transactions())
719
session->transaction.stmt.modified_non_trans_table= true;
720
end_read_record(&info);
721
if (session->killed && !local_error)
723
if (local_error == -1) // End of file
731
Send ok to the client
737
bool multi_delete::send_eof()
739
Session::killed_state killed_status= Session::NOT_KILLED;
740
session->set_proc_info("deleting from reference tables");
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/* Does deletes for the last n - 1 tables, returns 0 if ok */
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int local_error= do_deletes(); // returns 0 if success
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/* compute a total error to know if something failed */
746
local_error= local_error || error;
747
killed_status= (local_error == 0)? Session::NOT_KILLED : session->killed;
748
/* reset used flags */
749
session->set_proc_info("end");
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if ((local_error == 0) || session->transaction.stmt.modified_non_trans_table)
753
if (session->transaction.stmt.modified_non_trans_table)
754
session->transaction.all.modified_non_trans_table= true;
756
if (local_error != 0)
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error_handled= true; // to force early leave from ::send_error()
761
session->row_count_func= deleted;
762
session->my_ok((ha_rows) session->row_count_func);
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/***************************************************************************
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384
****************************************************************************/
added
removed
drizzled/sql_delete.cc
