#ifndef SQL_RECORDS_H
#define SQL_RECORDS_H
/* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
#ifdef USE_PRAGMA_INTERFACE
#pragma interface /* gcc class implementation */
#endif
#include "table.h"
struct st_join_table;
class handler;
class THD;
class SQL_SELECT;
class Copy_field;
class SORT_INFO;
struct READ_RECORD;
void end_read_record(READ_RECORD *info);
void free_cache(READ_RECORD *info);
/**
A context for reading through a single table using a chosen access method:
index read, scan, etc, use of cache, etc.
Use by:
READ_RECORD read_record;
init_read_record(&read_record, ...);
while (read_record.read_record())
{
...
}
end_read_record();
*/
struct READ_RECORD
{
typedef int (*Read_func)(READ_RECORD*);
typedef void (*Unlock_row_func)(st_join_table *);
typedef int (*Setup_func)(struct st_join_table*);
TABLE *table; /* Head-form */
Unlock_row_func unlock_row;
Read_func read_record_func;
Read_func read_record_func_and_unpack_calls;
THD *thd;
SQL_SELECT *select;
uint ref_length, reclength, rec_cache_size, error_offset;
/**
Counting records when reading result from filesort().
Used when filesort leaves the result in the filesort buffer.
*/
ha_rows unpack_counter;
uchar *ref_pos; /* pointer to form->refpos */
uchar *rec_buf; /* to read field values after filesort */
uchar *cache,*cache_pos,*cache_end,*read_positions;
/*
Structure storing information about sorting
*/
SORT_INFO *sort_info;
struct st_io_cache *io_cache;
bool print_error;
int read_record() { return read_record_func(this); }
uchar *record() const { return table->record[0]; }
/*
SJ-Materialization runtime may need to read fields from the materialized
table and unpack them into original table fields:
*/
Copy_field *copy_field;
Copy_field *copy_field_end;
public:
READ_RECORD() : table(NULL), cache(NULL) {}
~READ_RECORD() { end_read_record(this); }
};
bool init_read_record(READ_RECORD *info, THD *thd, TABLE *reg_form,
SQL_SELECT *select, SORT_INFO *sort,
int use_record_cache,
bool print_errors, bool disable_rr_cache);
bool init_read_record_idx(READ_RECORD *info, THD *thd, TABLE *table,
bool print_error, uint idx, bool reverse);
void rr_unlock_row(st_join_table *tab);
#endif /* SQL_RECORDS_H */
|