Functionality added or changed:
SHOW PROCESSLIST
command
WEEK() so that one can get
week number according to the ISO 8601 specification.
(Old code should still work).
INSERT DELAYED threads doesn't hang on Waiting for
INSERT when one sends a SIGHUP to mysqld.
AND works according to SQL-99 when it comes to
NULL handling. In practice, this only affects queries where you
do something like WHERE ... NOT (NULL AND 0).
mysqld will now resolve basedir to its full path (with
realpath()). This enables one to use relative symlinks to the
MySQL installation directory. This will however cause show
variables to report different directories on systems where there is
a symbolic link in the path.
IGNORE INDEX or USE INDEX.
to be ignored.
--use-frm option to mysqlcheck. When used with
REPAIR, it gets the table structure from the .frm file, so the
table can be repaired even if the .MYI header is corrupted.
MAX() optimisation when used with JOIN and
ON expressions.
BETWEEN behaviour changed (see section 6.3.1.2 Comparison Operators).
Now datetime_col BETWEEN timestamp AND timestamp should work
as expected.
TEMPORARY MERGE tables now.
DELETE FROM myisam_table now shrinks not only the `.MYD' file but
also the `.MYI' file.
--open-files-limit=# option to mysqld_safe
it's now passed on to mysqld.
EXPLAIN from 'where used' to
'Using where' to make it more in line with other output.
safe_show_database as it was no longer used.
automake 1.5 and
libtool 1.4.
--ignore-space) back to the
original --ignore-spaces in mysqlclient. (Both syntaxes will
work).
UPDATE privilege when using REPLACE.
DROP TEMPORARY TABLE ..., to be used to make
replication safer.
BEGIN/COMMIT are now stored in the binary log on
COMMIT and not stored if one does ROLLBACK. This fixes
some problems with non-transactional temporary tables used inside
transactions.
SELECT * FROM (t2 LEFT JOIN t3 USING (a)), t1 worked, but
not SELECT * FROM t1, (t2 LEFT JOIN t3 USING (a)). Note that
braces are simply removed, they do not change the way the join is
executed.
InnoDB now supports also isolation levels
READ UNCOMMITTED and READ COMMITTED.
For a detailed InnoDB changelog, see section 7.5.15 InnoDB Change History
in this manual.
Bugs fixed:
MAX() optimisation when used with JOIN and
ON expressions.
INSERT DELAY threads don't hang on Waiting for
INSERT when one sends a SIGHUP to mysqld.
IGNORE INDEX or USE INDEX.
root user in mysqld_safe.
CHECK
or REPAIR.
GROUP BY queries that
didn't return any result.
mysqlshow to work properly with wildcarded database names and
with database names that contain underscores.
MyISAM crash when using dynamic-row tables with huge numbers of
packed fields.
BDB transactions.
MATCH
relevance calculations.
IN BOOLEAN MODE that made MATCH
to return incorrect relevance value in some complex joins.
MyISAM key length to a value
slightly less that 500. It is exactly 500 now.
GROUP BY on columns that may have a NULL value
doesn't always use disk based temporary tables.
--des-key-file argument to mysqld
is interpreted relative to the data directory if given as a relative pathname.
NULL has to be MyISAM. This was okay for 3.23, but not
needed in 4.*. This resulted in slowdown in many queries since 4.0.2.
ORDER BY ... LIMIT row_count
to not return all rows.
REPAIR TABLE and myisamchk
to corrupt FULLTEXT indexes.
mysql grant table database. Now queries
in this database are not cached in the query cache.
mysqld_safe for some shells.
MyISAM MERGE table has more than 2 ^ 32 rows and
MySQL was not compiled with -DBIG_TABLES.
ORDER BY ... DESC problems with InnoDB tables.