mariadb/sql/ha_blackhole.cc
unknown 6116d0176b bug#10952
"alter table from MyISAM to MERGE lost data without errors and warnings"
  Add new handlerton flag which prevent user from altering table storage
  engine to storage engines which would lose data. Both 'blackhole' and 
  'merge' are marked with the new flag.
  Tests included.


mysql-test/r/blackhole.result:
  test for bug#10952
mysql-test/r/merge.result:
  test for bug#10952
mysql-test/t/blackhole.test:
  test for bug#10952
mysql-test/t/merge.test:
  test for bug#10952
sql/ha_blackhole.cc:
  Bug#10952
    shouldn't be able to alter a table into a blackhole
sql/ha_myisammrg.cc:
  Bug#10952
    shouldn't be able to alter a table into a merge
sql/handler.h:
  Bug#10952
    new handlerton flag
sql/sql_table.cc:
  Bug#10952
    If alter is changing engine, check if new engine allows creating table
    via ALTER statement.
2006-05-09 13:31:46 -07:00

230 lines
5.3 KiB
C++

/* Copyright (C) 2005 MySQL 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_IMPLEMENTATION
#pragma implementation // gcc: Class implementation
#endif
#include "mysql_priv.h"
#ifdef HAVE_BLACKHOLE_DB
#include "ha_blackhole.h"
/* Blackhole storage engine handlerton */
handlerton blackhole_hton= {
"BLACKHOLE",
SHOW_OPTION_YES,
"/dev/null storage engine (anything you write to it disappears)",
DB_TYPE_BLACKHOLE_DB,
NULL,
0, /* slot */
0, /* savepoint size. */
NULL, /* close_connection */
NULL, /* savepoint */
NULL, /* rollback to savepoint */
NULL, /* release savepoint */
NULL, /* commit */
NULL, /* rollback */
NULL, /* prepare */
NULL, /* recover */
NULL, /* commit_by_xid */
NULL, /* rollback_by_xid */
NULL, /* create_cursor_read_view */
NULL, /* set_cursor_read_view */
NULL, /* close_cursor_read_view */
HTON_CAN_RECREATE | HTON_ALTER_CANNOT_CREATE
};
/*****************************************************************************
** BLACKHOLE tables
*****************************************************************************/
ha_blackhole::ha_blackhole(TABLE *table_arg)
:handler(&blackhole_hton, table_arg)
{}
static const char *ha_blackhole_exts[] = {
NullS
};
const char **ha_blackhole::bas_ext() const
{
return ha_blackhole_exts;
}
int ha_blackhole::open(const char *name, int mode, uint test_if_locked)
{
DBUG_ENTER("ha_blackhole::open");
thr_lock_init(&thr_lock);
thr_lock_data_init(&thr_lock,&lock,NULL);
DBUG_RETURN(0);
}
int ha_blackhole::close(void)
{
DBUG_ENTER("ha_blackhole::close");
thr_lock_delete(&thr_lock);
DBUG_RETURN(0);
}
int ha_blackhole::create(const char *name, TABLE *table_arg,
HA_CREATE_INFO *create_info)
{
DBUG_ENTER("ha_blackhole::create");
DBUG_RETURN(0);
}
const char *ha_blackhole::index_type(uint key_number)
{
DBUG_ENTER("ha_blackhole::index_type");
DBUG_RETURN((table->key_info[key_number].flags & HA_FULLTEXT) ?
"FULLTEXT" :
(table->key_info[key_number].flags & HA_SPATIAL) ?
"SPATIAL" :
(table->key_info[key_number].algorithm == HA_KEY_ALG_RTREE) ?
"RTREE" :
"BTREE");
}
int ha_blackhole::write_row(byte * buf)
{
DBUG_ENTER("ha_blackhole::write_row");
DBUG_RETURN(0);
}
int ha_blackhole::rnd_init(bool scan)
{
DBUG_ENTER("ha_blackhole::rnd_init");
DBUG_RETURN(0);
}
int ha_blackhole::rnd_next(byte *buf)
{
DBUG_ENTER("ha_blackhole::rnd_next");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
int ha_blackhole::rnd_pos(byte * buf, byte *pos)
{
DBUG_ENTER("ha_blackhole::rnd_pos");
DBUG_ASSERT(0);
DBUG_RETURN(0);
}
void ha_blackhole::position(const byte *record)
{
DBUG_ENTER("ha_blackhole::position");
DBUG_ASSERT(0);
DBUG_VOID_RETURN;
}
void ha_blackhole::info(uint flag)
{
DBUG_ENTER("ha_blackhole::info");
records= 0;
deleted= 0;
errkey= 0;
mean_rec_length= 0;
data_file_length= 0;
index_file_length= 0;
max_data_file_length= 0;
delete_length= 0;
if (flag & HA_STATUS_AUTO)
auto_increment_value= 1;
DBUG_VOID_RETURN;
}
int ha_blackhole::external_lock(THD *thd, int lock_type)
{
DBUG_ENTER("ha_blackhole::external_lock");
DBUG_RETURN(0);
}
uint ha_blackhole::lock_count(void) const
{
DBUG_ENTER("ha_blackhole::lock_count");
DBUG_RETURN(0);
}
THR_LOCK_DATA **ha_blackhole::store_lock(THD *thd,
THR_LOCK_DATA **to,
enum thr_lock_type lock_type)
{
DBUG_ENTER("ha_blackhole::store_lock");
DBUG_RETURN(to);
}
int ha_blackhole::index_read(byte * buf, const byte * key,
uint key_len, enum ha_rkey_function find_flag)
{
DBUG_ENTER("ha_blackhole::index_read");
DBUG_RETURN(0);
}
int ha_blackhole::index_read_idx(byte * buf, uint idx, const byte * key,
uint key_len, enum ha_rkey_function find_flag)
{
DBUG_ENTER("ha_blackhole::index_read_idx");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
int ha_blackhole::index_read_last(byte * buf, const byte * key, uint key_len)
{
DBUG_ENTER("ha_blackhole::index_read_last");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
int ha_blackhole::index_next(byte * buf)
{
DBUG_ENTER("ha_blackhole::index_next");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
int ha_blackhole::index_prev(byte * buf)
{
DBUG_ENTER("ha_blackhole::index_prev");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
int ha_blackhole::index_first(byte * buf)
{
DBUG_ENTER("ha_blackhole::index_first");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
int ha_blackhole::index_last(byte * buf)
{
DBUG_ENTER("ha_blackhole::index_last");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
#endif /* HAVE_BLACKHOLE_DB */