Alterações na distribuição 3.23.2 (09 Aug 1999)
Fixed range optimiser bug: SELECT * FROM table_name WHERE key_part1 >= const AND (key_part2 = const OR key_part2 = const)
. The bug was that some rows could be duplicated in the result.
- Running
myisamchk
without-a
updated the index distribution incorrectly. SET SQL_LOW_PRIORITY_UPDATES=1
was causing a parse error.- You can now update index columns that are used in the
WHERE
clause.UPDATE tbl_name SET KEY=KEY+1 WHERE KEY > 100
- Date handling should now be a bit faster.
- Added handling of fuzzy dates (dates where day or month is 0), such as
'1999-01-00'
. - Fixed optimization of
SELECT ... WHERE key_part1=const1 AND key_part_2=const2 AND key_part1=const4 AND key_part2=const4
; indextype should berange
instead ofref
. - Fixed
egcs
1.1.2 optimiser bug (when usingBLOB
values) on Linux Alpha. - Fixed problem with
LOCK TABLES
combined withDELETE FROM table
. MyISAM
tables now allow keys onNULL
andBLOB/TEXT
columns.- The following join is now much faster:
SELECT ... FROM t1 LEFT JOIN t2 ON ... WHERE t2.not_null_column IS NULL
. ORDER BY
andGROUP BY
can be done on functions.- Changed handling of 'const_item' to allow handling of
ORDER BY RAND()
. - Indexes are now used for
WHERE key_column = function
. - Indexes are now used for
WHERE key_column = col_name
even if the columns are not identically packed. - Indexes are now used for
WHERE col_name IS NULL
. - Changed heap tables to be stored in low_byte_first order (to make it easy to convert to
MyISAM
tables) - Automatic change of
HEAP
temporary tables toMyISAM
tables in case oftable is full
errors. - Added
--init-file=file_name
option tomysqld
. - Added
COUNT(DISTINCT value, [value, ...])
. CREATE TEMPORARY TABLE
now creates a temporary table, in its own namespace, that is automatically deleted if connection is dropped.- New reserved words (required for
CASE
):CASE, THEN, WHEN, ELSE and END
. - New functions
EXPORT_SET()
andMD5()
. - Support for the GB2312 Chinese character set.