Version for 4.0.
It fixes two problems:
1. The cause of the bug was that we did not check the table version for
the HANDLER ... READ commands. We did not notice when a table was
replaced by a new one. This can happen during ALTER TABLE, REPAIR
TABLE, and OPTIMIZE TABLE (there might be more cases). I call the fix
for this problem "the primary bug fix".
2. mysql_ha_flush() was not always called with a locked LOCK_open.
Though the function comment clearly said it must.
I changed the code so that the locking is done when required. I call
the fix for this problem "the secondary fix".
1.) Added a new option to mysql_lock_tables() for ignoring FLUSH TABLES.
Used the new option in create_table_from_items().
It is necessary to prevent the SELECT table from being reopend.
It would get new storage assigned for its fields, while the
SELECT part of the command would still use the old (freed) storage.
2.) Protected the CREATE TABLE and CREATE TABLE ... SELECT commands
against a global read lock. This prevents a deadlock in
CREATE TABLE ... SELECT in conjunction with FLUSH TABLES WITH READ LOCK
and avoids the creation of new tables during a global read lock.
3.) Replaced set_protect_against_global_read_lock() and
unset_protect_against_global_read_lock() by
wait_if_global_read_lock() and start_waiting_global_read_lock()
in the INSERT DELAYED handling.
BUG#4335 - one name can be handler open'ed many times.
Reworked the HANDLER functions and interface.
Using a HASH to store information on open tables that
survives FLUSH TABLE.
HANDLER tables alias names must now be unique, though it
is allowed in 4.0 to qualify them with the database name
of the base table.
(All commit emails since 4.0.1 checked)
This had to be done now, before the 4.1 tree changes to much, to make it easy to propagate bug fixes to the 4.1 tree.
Test of unsigned BIGINT values
Fixes for queries-per-hour
Cleanup of replication code (comments and portability fixes)
Make most of the binary log code 4G clean
Changed syntax for GRANT ... QUERIES PER HOUR
New faster list iterators
Change list code to be simpler and faster
Optimize count(distinct)
New error messages for UNION
Make create_tmp_table more general to be usable by UNION