ha_isam.h
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:3k
- /* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
- 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; either version 2 of the License, or
- (at your option) any later version.
- 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
- #ifdef USE_PRAGMA_INTERFACE
- #pragma interface /* gcc class implementation */
- #endif
- /* class for the the myisam handler */
- #include <nisam.h>
- class ha_isam: public handler
- {
- N_INFO *file;
- /* We need this as table_flags() may change after open() */
- ulong int_table_flags;
- public:
- ha_isam(TABLE *table)
- :handler(table), file(0),
- int_table_flags(HA_READ_RND_SAME |
- HA_DUPP_POS | HA_NOT_DELETE_WITH_CACHE | HA_FILE_BASED)
- {}
- ~ha_isam() {}
- ulong index_flags(uint idx, uint part, bool all_parts) const
- { return HA_READ_NEXT; } // but no HA_READ_PREV here!!!
- const char *table_type() const { return "ISAM"; }
- const char *index_type(uint key_number) { return "BTREE"; }
- const char **bas_ext() const;
- ulong table_flags() const { return int_table_flags; }
- uint max_supported_record_length() const { return HA_MAX_REC_LENGTH; }
- uint max_supported_keys() const { return N_MAXKEY; }
- uint max_supported_key_parts() const { return N_MAXKEY_SEG; }
- uint max_supported_key_length() const { return N_MAX_KEY_LENGTH; }
- uint min_record_length(uint options) const;
- bool low_byte_first() const { return 0; }
- int open(const char *name, int mode, uint test_if_locked);
- int close(void);
- int write_row(byte * buf);
- int update_row(const byte * old_data, byte * new_data);
- int delete_row(const byte * buf);
- int index_read(byte * buf, const byte * key,
- uint key_len, enum ha_rkey_function find_flag);
- int index_read_idx(byte * buf, uint idx, const byte * key,
- uint key_len, enum ha_rkey_function find_flag);
- int index_read_last(byte * buf, const byte * key, uint key_len);
- int index_next(byte * buf);
- int index_prev(byte * buf);
- int index_first(byte * buf);
- int index_last(byte * buf);
- int rnd_init(bool scan);
- int rnd_next(byte *buf);
- int rnd_pos(byte * buf, byte *pos);
- void position(const byte *record);
- void info(uint);
- int extra(enum ha_extra_function operation);
- int external_lock(THD *thd, int lock_type);
- ha_rows records_in_range(uint inx, key_range *min_key, key_range *max_key);
- int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info);
- THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to,
- enum thr_lock_type lock_type);
- };