Dear Dan,
Thanks for your reply.
I've already done OPTIMIZE for all tables.
I suppose that's the same as rebuilding the indices.
Tim
At 01:26 AM 7-2-2001 -0800, you wrote:
>i've heard it said that every so often (eg every month) you need to rebuild
>indexes on tables, as over time they lose their performance enhancement.
>could that be true?
>
>dan
>
>
>-----Original Message-----
>From: Tim Samshuijzen [mailto:[EMAIL PROTECTED]]
>Sent: Tuesday, 6 February 2001 04:50
>To: [EMAIL PROTECTED]
>Subject: Re: amazingly slow
>
>
>
>
>Dear Dave,
>
>Thanks for your reply.
>
>(The table actually works with word numbers, as the words
>are present in a hash table. I explained it the way I did
>because functionally it is the same. So the actual search
>is for WordNumber values instead of Word values.)
>
>I did the EXPLAIN as you suggested.
>
>Here is the output:
>
>mysql> EXPLAIN SELECT B.* FROM maintable AS B ,
> -> wordindex AS YL1 ,
> -> wordindex AS YL2 ,
> -> wordindex AS YL3 WHERE
> -> YL1.WordNumber = 123 AND
> -> YL1.RecordNumber = B.RecordNumber AND
> -> YL2.WordNumber = 345 AND
> -> YL2.RecordNumber = B.RecordNumber AND
> -> YL3.WordNumber = 678 AND
> -> YL3.RecordNumber = B.RecordNumber AND
> -> B.Price >= 1000
> -> LIMIT 0,51;
>+-----+------+-----------------------+------------+-------+----------------+
>----+----------+
>|table|type |possible_keys |key |key_len|ref
>|rows|Extra |
>+-----+------+-----------------------+------------+-------+----------------+
>----+----------+
>|YL3 |ref |WordNumber,RecordNumber|WordNumber | 4 |???
>| 1 | |
>|B |eq_ref|PRIMARY |PRIMARY | 4
>|YL3.RecordNumber| 1 |where used|
>|YL2 |ref |WordNumber,RecordNumber|RecordNumber| 4 |B.RecordNumber
>| 23 |where used|
>|YL1 |ref |WordNumber,RecordNumber|RecordNumber| 4 |B.RecordNumber
>| 23 |where used|
>+-----+------+-----------------------+------------+-------+----------------+
>----+----------+
>4 rows in set (0.01 sec)
>
>
>This still does not tell me why the query is amazingly slow.
>
>Tim
>
>
>At 10:52 AM 6-2-2001 +0000, you wrote:
>>Tim Samshuijzen <[EMAIL PROTECTED]> writes:
>>
>>> Anyone out there who wants to save me and our company?
>>
>>You missed the important first step: EXPLAIN the query.
>>
>>--
>>Dave Hodgkinson, http://www.hodgkinson.org
>>Editor-in-chief, The Highway Star http://www.deep-purple.com
>> Apache, mod_perl, MySQL, Sybase hired gun for, well, hire
>> -----------------------------------------------------------------
>>
>>---------------------------------------------------------------------
>>Before posting, please check:
>> http://www.mysql.com/manual.php (the manual)
>> http://lists.mysql.com/ (the list archive)
>>
>>To request this thread, e-mail <[EMAIL PROTECTED]>
>>To unsubscribe, e-mail
><[EMAIL PROTECTED]>
>>Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
>>
>>
>>
>
>
>---------------------------------------------------------------------
>Before posting, please check:
> http://www.mysql.com/manual.php (the manual)
> http://lists.mysql.com/ (the list archive)
>
>To request this thread, e-mail <[EMAIL PROTECTED]>
>To unsubscribe, e-mail
><[EMAIL PROTECTED]>
>Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
>
>
>
>---------------------------------------------------------------------
>Before posting, please check:
> http://www.mysql.com/manual.php (the manual)
> http://lists.mysql.com/ (the list archive)
>
>To request this thread, e-mail <[EMAIL PROTECTED]>
>To unsubscribe, e-mail
<[EMAIL PROTECTED]>
>Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
>
>
>
---------------------------------------------------------------------
Before posting, please check:
http://www.mysql.com/manual.php (the manual)
http://lists.mysql.com/ (the list archive)
To request this thread, e-mail <[EMAIL PROTECTED]>
To unsubscribe, e-mail <[EMAIL PROTECTED]>
Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
