diff options
Diffstat (limited to 'storage/maria/ma_rkey.c')
| -rw-r--r-- | storage/maria/ma_rkey.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/storage/maria/ma_rkey.c b/storage/maria/ma_rkey.c new file mode 100644 index 00000000000..c9653d30110 --- /dev/null +++ b/storage/maria/ma_rkey.c @@ -0,0 +1,178 @@ +/* Copyright (C) 2006 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; 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + +/* Read record based on a key */ + +#include "maria_def.h" +#include "ma_rt_index.h" + + /* Read a record using key */ + /* Ordinary search_flag is 0 ; Give error if no record with key */ + +int maria_rkey(MARIA_HA *info, uchar *buf, int inx, const uchar *key, + key_part_map keypart_map, enum ha_rkey_function search_flag) +{ + uchar *key_buff; + MARIA_SHARE *share=info->s; + MARIA_KEYDEF *keyinfo; + HA_KEYSEG *last_used_keyseg; + uint pack_key_length, use_key_length, nextflag; + DBUG_ENTER("maria_rkey"); + DBUG_PRINT("enter", ("base: 0x%lx buf: 0x%lx inx: %d search_flag: %d", + (long) info, (long) buf, inx, search_flag)); + + if ((inx = _ma_check_index(info,inx)) < 0) + DBUG_RETURN(my_errno); + + info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED); + info->last_key_func= search_flag; + keyinfo= share->keyinfo + inx; + + if (info->once_flags & USE_PACKED_KEYS) + { + info->once_flags&= ~USE_PACKED_KEYS; /* Reset flag */ + /* + key is already packed!; This happens when we are using a MERGE TABLE + */ + key_buff= info->lastkey+info->s->base.max_key_length; + pack_key_length= keypart_map; + bmove(key_buff, key, pack_key_length); + last_used_keyseg= info->s->keyinfo[inx].seg + info->last_used_keyseg; + } + else + { + DBUG_ASSERT(keypart_map); + /* Save the packed key for later use in the second buffer of lastkey. */ + key_buff=info->lastkey+info->s->base.max_key_length; + pack_key_length= _ma_pack_key(info,(uint) inx, key_buff, key, + keypart_map, &last_used_keyseg); + /* Save packed_key_length for use by the MERGE engine. */ + info->pack_key_length= pack_key_length; + info->last_used_keyseg= (uint16) (last_used_keyseg - + info->s->keyinfo[inx].seg); + DBUG_EXECUTE("key", _ma_print_key(DBUG_FILE, keyinfo->seg, + key_buff, pack_key_length);); + } + + if (fast_ma_readinfo(info)) + goto err; + if (share->concurrent_insert) + rw_rdlock(&share->key_root_lock[inx]); + + nextflag=maria_read_vec[search_flag]; + use_key_length=pack_key_length; + if (!(nextflag & (SEARCH_FIND | SEARCH_NO_FIND | SEARCH_LAST))) + use_key_length=USE_WHOLE_KEY; + + switch (info->s->keyinfo[inx].key_alg) { +#ifdef HAVE_RTREE_KEYS + case HA_KEY_ALG_RTREE: + if (maria_rtree_find_first(info,inx,key_buff,use_key_length,nextflag) < 0) + { + maria_print_error(info->s, HA_ERR_CRASHED); + my_errno= HA_ERR_CRASHED; + info->cur_row.lastpos= HA_OFFSET_ERROR; + } + break; +#endif + case HA_KEY_ALG_BTREE: + default: + if (!_ma_search(info, keyinfo, key_buff, use_key_length, + maria_read_vec[search_flag], + info->s->state.key_root[inx]) && + share->concurrent_insert) + { + /* + If we searching for a partial key (or using >, >=, < or <=) and + the data is outside of the data file, we need to continue searching + for the first key inside the data file + */ + if (info->cur_row.lastpos >= info->state->data_file_length && + (search_flag != HA_READ_KEY_EXACT || + last_used_keyseg != keyinfo->seg + keyinfo->keysegs)) + { + do + { + uint not_used[2]; + /* + Skip rows that are inserted by other threads since we got a lock + Note that this can only happen if we are not searching after an + full length exact key, because the keys are sorted + according to position + */ + if (_ma_search_next(info, keyinfo, info->lastkey, + info->lastkey_length, + maria_readnext_vec[search_flag], + info->s->state.key_root[inx])) + break; + /* + Check that the found key does still match the search. + _ma_search_next() delivers the next key regardless of its + value. + */ + if (search_flag == HA_READ_KEY_EXACT && + ha_key_cmp(keyinfo->seg, (uchar*) key_buff, + (uchar*) info->lastkey, use_key_length, + SEARCH_FIND, not_used)) + { + my_errno= HA_ERR_KEY_NOT_FOUND; + info->cur_row.lastpos= HA_OFFSET_ERROR; + break; + } + } while (info->cur_row.lastpos >= info->state->data_file_length); + } + } + } + if (share->concurrent_insert) + rw_unlock(&share->key_root_lock[inx]); + + if (info->cur_row.lastpos == HA_OFFSET_ERROR) + { + fast_ma_writeinfo(info); + goto err; + } + + /* Calculate length of the found key; Used by maria_rnext_same */ + if ((keyinfo->flag & HA_VAR_LENGTH_KEY) && last_used_keyseg) + info->last_rkey_length= _ma_keylength_part(keyinfo, info->lastkey, + last_used_keyseg); + else + info->last_rkey_length= pack_key_length; + + /* Check if we don't want to have record back, only error message */ + if (!buf) + { + fast_ma_writeinfo(info); + DBUG_RETURN(0); + } + if (!(*info->read_record)(info, buf, info->cur_row.lastpos)) + { + info->update|= HA_STATE_AKTIV; /* Record is read */ + DBUG_RETURN(0); + } + + info->cur_row.lastpos= HA_OFFSET_ERROR; /* Didn't find row */ + +err: + /* Store last used key as a base for read next */ + memcpy(info->lastkey,key_buff,pack_key_length); + info->last_rkey_length= pack_key_length; + bzero((char*) info->lastkey+pack_key_length,info->s->base.rec_reflength); + info->lastkey_length=pack_key_length+info->s->base.rec_reflength; + + if (search_flag == HA_READ_AFTER_KEY) + info->update|=HA_STATE_NEXT_FOUND; /* Previous gives last row */ + DBUG_RETURN(my_errno); +} /* _ma_rkey */ |