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https://github.com/MariaDB/server.git
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8d85715d50
Rowid Filter check is just like Index Condition Pushdown check: before we check the filter, we must check if we have walked out of the range we are scanning. (If we did, we should return, and not continue the scan). Consequences of this: - Rowid filtering doesn't work for keys that have partially-covered blob columns (just like Index Condition Pushdown) - The rowid filter function has three return values: CHECK_POS (passed) CHECK_NEG (filtered out), CHECK_OUT_OF_RANGE. All of the above is implemented in this patch
122 lines
3.8 KiB
C
122 lines
3.8 KiB
C
/* Copyright (C) 2006 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; version 2 of the License.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA */
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#include "maria_def.h"
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#include "ma_rt_index.h"
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/*
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Read next row with the same key as previous read, but abort if
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the key changes.
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One may have done a write, update or delete of the previous row.
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NOTE! Even if one changes the previous row, the next read is done
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based on the position of the last used key!
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*/
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int maria_rnext_same(MARIA_HA *info, uchar *buf)
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{
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int error;
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uint inx,not_used[2];
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MARIA_KEYDEF *keyinfo;
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check_result_t check= CHECK_POS;
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DBUG_ENTER("maria_rnext_same");
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if ((int) (inx= info->lastinx) < 0 ||
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info->cur_row.lastpos == HA_OFFSET_ERROR)
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DBUG_RETURN(my_errno=HA_ERR_WRONG_INDEX);
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if (fast_ma_readinfo(info))
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DBUG_RETURN(my_errno);
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keyinfo= info->s->keyinfo+inx;
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if (info->s->lock_key_trees)
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mysql_rwlock_rdlock(&keyinfo->root_lock);
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switch (keyinfo->key_alg) {
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#ifdef HAVE_RTREE_KEYS
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case HA_KEY_ALG_RTREE:
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if ((error=maria_rtree_find_next(info,inx,
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maria_read_vec[info->last_key_func])))
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{
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error=1;
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my_errno=HA_ERR_END_OF_FILE;
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info->cur_row.lastpos= HA_OFFSET_ERROR;
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break;
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}
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break;
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#endif
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case HA_KEY_ALG_BTREE:
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default:
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if (!(info->update & HA_STATE_RNEXT_SAME))
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{
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/* First rnext_same; Store old key */
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memcpy(info->lastkey_buff2, info->last_key.data,
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info->last_rkey_length);
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}
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for (;;)
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{
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if ((error= _ma_search_next(info, &info->last_key,
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SEARCH_BIGGER,
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info->s->state.key_root[inx])))
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break;
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if (ha_key_cmp(keyinfo->seg, info->last_key.data,
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info->lastkey_buff2,
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info->last_rkey_length, SEARCH_FIND,
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not_used))
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{
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error=1;
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my_errno=HA_ERR_END_OF_FILE;
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info->cur_row.lastpos= HA_OFFSET_ERROR;
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break;
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}
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/*
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If we are at the last key on the key page, allow writers to
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access the index.
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*/
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if (info->int_keypos >= info->int_maxpos &&
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ma_yield_and_check_if_killed(info, inx))
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{
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error= 1;
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break;
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}
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/* Skip rows that are inserted by other threads since we got a lock */
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if ((info->s->row_is_visible)(info) &&
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((check= ma_check_index_cond(info, inx, buf)) != CHECK_NEG))
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break;
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}
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}
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if (info->s->lock_key_trees)
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mysql_rwlock_unlock(&keyinfo->root_lock);
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/* Don't clear if database-changed */
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info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
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info->update|= HA_STATE_NEXT_FOUND | HA_STATE_RNEXT_SAME;
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if (error || check != CHECK_POS)
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{
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fast_ma_writeinfo(info);
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if (my_errno == HA_ERR_KEY_NOT_FOUND)
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my_errno= HA_ERR_END_OF_FILE;
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}
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else if (!buf)
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{
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fast_ma_writeinfo(info);
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DBUG_RETURN(info->cur_row.lastpos == HA_OFFSET_ERROR ? my_errno : 0);
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}
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else if (!(*info->read_record)(info, buf, info->cur_row.lastpos))
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{
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info->update|= HA_STATE_AKTIV; /* Record is read */
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DBUG_RETURN(0);
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}
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DBUG_RETURN(my_errno);
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} /* maria_rnext_same */
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