1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
/* 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 */
/* Remove all rows from a MyISAM table */
/* This clears the status information and truncates files */
#include "myisamdef.h"
int mi_delete_all_rows(MI_INFO *info)
{
uint i;
MYISAM_SHARE *share=info->s;
MI_STATE_INFO *state=&share->state;
DBUG_ENTER("mi_delete_all_rows");
if (share->options & HA_OPTION_READ_ONLY_DATA)
{
DBUG_RETURN(my_errno=EACCES);
}
if (_mi_readinfo(info,F_WRLCK,1))
DBUG_RETURN(my_errno);
if (_mi_mark_file_changed(info))
goto err;
info->state->records=info->state->del=state->split=0;
state->dellink = HA_OFFSET_ERROR;
state->sortkey= (ushort) ~0;
info->state->key_file_length=share->base.keystart;
info->state->data_file_length=0;
info->state->empty=info->state->key_empty=0;
state->checksum=0;
for (i=share->base.max_key_block_length/MI_MIN_KEY_BLOCK_LENGTH ; i-- ; )
state->key_del[i]= HA_OFFSET_ERROR;
for (i=0 ; i < share->base.keys ; i++)
state->key_root[i]= HA_OFFSET_ERROR;
myisam_log_command(MI_LOG_DELETE_ALL,info,(byte*) 0,0,0);
/*
If we are using delayed keys or if the user has done changes to the tables
since it was locked then there may be key blocks in the key cache
*/
flush_key_blocks(share->kfile, FLUSH_IGNORE_CHANGED);
if (my_chsize(info->dfile, 0, 0, MYF(MY_WME)) ||
my_chsize(share->kfile, share->base.keystart, 0, MYF(MY_WME)) )
goto err;
VOID(_mi_writeinfo(info,WRITEINFO_UPDATE_KEYFILE));
allow_break(); /* Allow SIGHUP & SIGINT */
DBUG_RETURN(0);
err:
{
int save_errno=my_errno;
VOID(_mi_writeinfo(info,WRITEINFO_UPDATE_KEYFILE));
info->update|=HA_STATE_WRITTEN; /* Buffer changed */
allow_break(); /* Allow SIGHUP & SIGINT */
DBUG_RETURN(my_errno=save_errno);
}
} /* mi_delete */
|
