Comments on: COUNT(*) for Innodb Tables http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/ Everything about MySQL Performance Sun, 07 Sep 2008 07:48:22 +0000 http://wordpress.org/?v=2.5.1 By: peter http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-331977 peter Sun, 20 Jul 2008 16:04:46 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-331977 Ries, Kishore Indeed 3000 records is very small unless these are 10MB faxes stored directly in the database :) Wrong indexing or query which MySQL can't optimize well is likely reason. If you report the EXPLAIN on our forums we might be able to help. Ries, Kishore

Indeed 3000 records is very small unless these are 10MB faxes stored directly in the database :) Wrong indexing or query which MySQL can’t optimize well is likely reason. If you report the EXPLAIN on our forums we might be able to help.

]]> By: Ries van Twisk http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-330847 Ries van Twisk Fri, 18 Jul 2008 14:33:22 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-330847 to Kishore. I you need to read upon SQL, usage of indexes etc. 3000 records is nothing for any DB and shouldn't be slow in any case. Most likely your DB is not properly normalized and you don't have proper indexes. Ries to Kishore.

I you need to read upon SQL, usage of indexes etc. 3000 records is nothing for any DB and shouldn’t be slow in any case.
Most likely your DB is not properly normalized and you don’t have proper indexes.

Ries

]]> By: Kishore http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-317431 Kishore Wed, 25 Jun 2008 05:54:43 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-317431 Dear Friends, I am getting headache with MySql. I am new to .net and MYSQl. At present lots of Issues occured in MySql ...but the problem is slow.. "Whenever We are executing the Query it is taking lot'z of time to execute. Our tables contains nearly 3000 records..." How can I optimize the Stored procedures.. (or) How can I change this Sp into faster manner... "Thanks In advance" Dear Friends,
I am getting headache with MySql. I am new to .net and MYSQl.
At present lots of Issues occured in MySql …but the problem is slow..
“Whenever We are executing the Query it is taking lot’z of time to execute. Our tables contains nearly 3000 records…”
How can I optimize the Stored procedures..
(or)
How can I change this Sp into faster manner…
“Thanks In advance”

]]> By: John Swapceinski http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-283794 John Swapceinski Sun, 20 Apr 2008 18:20:49 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-283794 If you want a quick and dirty count of the number of rows in a InnoDB table, this seems to work: explain select count(*) from Table; The result is fast and will give you a "rows" count that should be within 10% of the number of rows in the Table. So it seems the row count is being cached SOMEWHERE (I don't know where). BTW, I am using MySQL v5.0.45. If you want a quick and dirty count of the number of rows in a InnoDB table, this seems to work:

explain select count(*) from Table;

The result is fast and will give you a “rows” count that should be within 10% of the number of rows in the Table. So it seems the row count is being cached SOMEWHERE (I don’t know where). BTW, I am using MySQL v5.0.45.

]]> By: Technocation, Inc. http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-166496 Technocation, Inc. Wed, 12 Sep 2007 02:31:46 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-166496 <strong>OurSQL Episode 2: Wild Performance Tips...</strong> ... OurSQL Episode 2: Wild Performance Tips…

…

]]> By: GSIY … Ruby-Rails Portal http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-163866 GSIY … Ruby-Rails Portal Wed, 05 Sep 2007 16:00:41 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-163866 [...] of transactions, foreign keys and other niceties, you might be aware of its limitations, like much slower count(*). Our DBAs are in a constant lookout for slow queries in production and the ways to keep DBs happy [...] [...] of transactions, foreign keys and other niceties, you might be aware of its limitations, like much slower count(*). Our DBAs are in a constant lookout for slow queries in production and the ways to keep DBs happy [...]

]]> By: kiran http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-156096 kiran Wed, 15 Aug 2007 09:24:17 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-156096 How to find the top values of table row? How to find the top values of table row?

]]> By: John http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-136742 John Mon, 18 Jun 2007 05:14:10 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-136742 I am seeing a query take up to 2 seconds (viewing the listing of members in my site) because at the top there's a count. What steps can I take to speed this up? I've thought about doing a quick count total cache stored in a separate field, but that won't work either, because depending on the search criteria, the count number can change at any time. I am seeing a query take up to 2 seconds (viewing the listing of members in my site) because at the top there’s a count. What steps can I take to speed this up? I’ve thought about doing a quick count total cache stored in a separate field, but that won’t work either, because depending on the search criteria, the count number can change at any time.

]]> By: puRe aka Marcel Oelke » MySQL Performance: Use counter tables http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-101630 puRe aka Marcel Oelke » MySQL Performance: Use counter tables Tue, 03 Apr 2007 11:16:59 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-101630 [...] I guess many of you know, that using SELECT count(*) FROM table is problematic and slow when using Innodb tables. This actually only applies to COUNT(*) queries without WHERE a clause as mentioned in the MySQL Performance Blog. [...] [...] I guess many of you know, that using SELECT count(*) FROM table is problematic and slow when using Innodb tables. This actually only applies to COUNT(*) queries without WHERE a clause as mentioned in the MySQL Performance Blog. [...]

]]> By: peter http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-25642 peter Thu, 28 Dec 2006 12:40:50 +0000 http://www.mysqlperformanceblog.com/2006/12/01/count-for-innodb-tables/#comment-25642 Sean, The question in this case is semantics. SELECT COUNT(*) must return accurate value by standards, There is no way it would be made to return wrong data by default as this may break some application. So we're speaking about option which will need to be specified such as inaccurate_count=1 ? Still not everyone will be able to use it because single instance can be shared by multiple applications. Having Some form of SQL FLAG, such as SELECT APPROXIMATE COUNT(*) would be better but will require application changes and at the same time one could use info from SHOW TABLE STATUS. Sean,

The question in this case is semantics. SELECT COUNT(*) must return accurate value by standards, There is no way it would be made to return wrong data by default as this may break some application. So we’re speaking about option which will need to be specified such as inaccurate_count=1 ? Still not everyone will be able to use it because single instance can be shared by multiple applications. Having Some form of SQL FLAG, such as SELECT APPROXIMATE COUNT(*) would be better but will require application changes and at the same time one could use info from SHOW TABLE STATUS.

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