Oh,
If any char fields add to index key ,then the =' ' gets wrong .
ordno, qty ,mem
1
3
5
aaa18
b 20
1. CREATE TABLE `t1` (
`mid` int(11) NOT NULL,
`qty` decimal(12,2) NOT NULL DEFAULT '0.00',
`ordno` char(8) NOT NULL
I am using MySQL 5.1.30 (MyISAM) and the query optimizer is quite bad at
choosing the proper index.
I often have to force it to use the correct index for Select statements,
otherwise takes 50x to 100x slower than it should be.
Has the query optiimizer improved any for later MySQL versions?
Mike,
Has the query optiimizer improved any for later MySQL versions?
Have a look at http://dev.mysql.com/tech-resources/articles/mysql-54.html.
Peter Brawley
http://www.artfulsoftware.com
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mos wrote:
I am using MySQL 5.1.30 (MyISAM) and the query optimizer is quite bad
at choosing
Wang,
select * from t1 where ordno=' '
gets wrong result 2 rows
I doubt you'll get many helpful responses till you post the INSERTs.
PB
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wang shuming wrote:
Oh,
If any char fields add to index key ,then the =' ' gets wrong .
ordno, qty ,mem
1
3
hello erveryone, I have a question about mysqldump.I have some blob data,
someone tell me mysqldump the data must use hex-blob options, why?
