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#ifndef DRIZZLED_SJ_TMP_TABLE_H
#define DRIZZLED_SJ_TMP_TABLE_H
#include <drizzled/server_includes.h>
#include "table.h"
/*
Describes use of one temporary table to weed out join duplicates.
The temporar
Used to
- create a temp table
- when we reach the weed-out tab, walk through rowid-ed tabs and
and copy rowids.
For each table we need
- rowid offset
- null bit address.
*/
class SJ_TMP_TABLE : public Sql_alloc
{
public:
/* Array of pointers to tables that should be "used" */
class TAB
{
public:
struct st_join_table *join_tab;
uint rowid_offset;
ushort null_byte;
uchar null_bit;
};
TAB *tabs;
TAB *tabs_end;
uint null_bits;
uint null_bytes;
uint rowid_len;
Table *tmp_table;
MI_COLUMNDEF *start_recinfo;
MI_COLUMNDEF *recinfo;
/* Pointer to next table (next->start_idx > this->end_idx) */
SJ_TMP_TABLE *next;
};
Table *create_duplicate_weedout_tmp_table(THD *thd,
uint uniq_tuple_length_arg,
SJ_TMP_TABLE *sjtbl);
#endif /* DRIZZLED_SJ_TMP_TABLE_H */
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