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by brian
clean slate |
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/* Copyright (C) 2000-2006 MySQL 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
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#include "myisamdef.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 mi_rnext_same(MI_INFO *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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MI_KEYDEF *keyinfo; |
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if ((int) (inx=info->lastinx) < 0 || info->lastpos == HA_OFFSET_ERROR) |
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51.1.109
by Jay Pipes
Removed/replaced DBUG |
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return(my_errno=HA_ERR_WRONG_INDEX); |
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1
by brian
clean slate |
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keyinfo=info->s->keyinfo+inx; |
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if (fast_mi_readinfo(info)) |
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51.1.109
by Jay Pipes
Removed/replaced DBUG |
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return(my_errno); |
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1
by brian
clean slate |
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if (info->s->concurrent_insert) |
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rw_rdlock(&info->s->key_root_lock[inx]); |
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switch (keyinfo->key_alg) |
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{
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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->lastkey2,info->lastkey,info->last_rkey_length); |
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}
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for (;;) |
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{
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if ((error=_mi_search_next(info,keyinfo,info->lastkey, |
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info->lastkey_length,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->lastkey, info->lastkey2, |
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info->last_rkey_length, SEARCH_FIND, 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->lastpos= HA_OFFSET_ERROR; |
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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->lastpos < info->state->data_file_length && |
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(!info->index_cond_func || mi_check_index_cond(info, inx, buf))) |
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break; |
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}
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}
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if (info->s->concurrent_insert) |
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rw_unlock(&info->s->key_root_lock[inx]); |
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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) |
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{
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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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51.1.109
by Jay Pipes
Removed/replaced DBUG |
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return(info->lastpos==HA_OFFSET_ERROR ? my_errno : 0); |
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1
by brian
clean slate |
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}
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else if (!(*info->read_record)(info,info->lastpos,buf)) |
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{
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info->update|= HA_STATE_AKTIV; /* Record is read */ |
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51.1.109
by Jay Pipes
Removed/replaced DBUG |
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return(0); |
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by brian
clean slate |
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}
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51.1.109
by Jay Pipes
Removed/replaced DBUG |
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return(my_errno); |
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1
by brian
clean slate |
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} /* mi_rnext_same */ |