Hi!
>>>>> "MARK" == MARK CALLAGHAN <mdcallag@stripped> writes:
MARK> I would like to know within ha_myisam::open() that the table to be
MARK> opened is a temp table. Code in ha_myisam:open expects the flag
MARK> HA_OPEN_TMP_TABLE to be set in some cases, but it is not set for my
MARK> case. This is true for MySQL 5.0.37 and appears to be true for 5.0.75.
MARK> Why is HA_OPEN_TMP_TABLE not set?
MARK> int ha_myisam::open(const char *name, int mode, uint test_if_locked)
<cut>
MARK> The caller has code to set HA_OPEN_TMP_TABLE:
MARK> if ((ha_err= (outparam->file->
MARK> ha_open(index_file,
MARK> (db_stat & HA_READ_ONLY ? O_RDONLY : O_RDWR),
MARK> (db_stat & HA_OPEN_TEMPORARY ? HA_OPEN_TMP_TABLE :
MARK> ((db_stat & HA_WAIT_IF_LOCKED) ||
MARK> (specialflag & SPECIAL_WAIT_IF_LOCKED)) ?
MARK> HA_OPEN_WAIT_IF_LOCKED :
MARK> (db_stat & (HA_ABORT_IF_LOCKED | HA_GET_INFO)) ?
MARK> HA_OPEN_ABORT_IF_LOCKED :
MARK> HA_OPEN_IGNORE_IF_LOCKED) | ha_open_flags))))
MARK> The call stack for this is listed. test_if_locked == 2 so the only
MARK> flag set is HA_OPEN_IGNORE_IF_LOCKED.
MARK> When openfrm is called, db_stat == 7, so HA_OPEN_KEYFILE,
MARK> HA_OPEN_RNDFILE and HA_GET_INDEX are set but HA_OPEN_TEMPORARY is not.
MARK> openfrm is called by open_temporary_table and open_temporary_table
MARK> _never_ passes HA_OPEN_TEMPORARY
The reason is that originally HA_OPEN_TEMPORARY was only meant to be
used for internal temporary tables, not explicitely created ones.
In MySQL 5.1 I split the flag to HA_OPEN_TMP_TABLE and
HA_OPEN_INTERNAL_TABLE and now we should change to set
HA_OPEN_TEMPORARY and thus HA_OPEN_TMP_TABLE also for explicit
temporary tables.
I checked the MyISAM code and don't see any obvious reason why we
couldn't do this change in MySQL 5.0 too.
Regards,
Monty
