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64

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3

This is a broad example of a SELECT query I use frequently on one of my sites. We are having very bad issues with slow load page times with our host, so I am trying to do everything I can to optimize every bit of code the site uses. I am no expert when it comes to MySQL, so I am hoping some of you may be of assistance. Here is the query I am trying to optimize a bit more -

Select ID, Col1, Col2, Col3, Col4, Col5, Col6, Col7, Col8, Col9, Col10, Col11, Col12, Col13, Col14, Col15 From table_1
Where Active = '1' And Col2 LIKE '%Cat%' And Col3 <> 'blah' And Col3 <> 'blah1'  And Col3 <> 'blah2' And Col3 <> 'blah3' And Col3 <> 'blah4' And Col3 <> 'blah5' And Col3 <> 'blah6'
And ID Not In (Select t2ID From table_2 Where table_2.t2ID = table_1.ID And table_2.Col1 = '1' And table_2.Col2 = '1')
And ID Not In (Select t3ID From table_3 Where table_3.t3ID = table_1.ID And table_3.Col1 = '1')
And ID Not In (Select t4ID From table_4 Where table_4.t4ID = table_1.ID And table_4.Col1 = '1')

Basically it checks 1 table (table_1) and pulls all the rows that match that are not found in table_2, table_3, and table_4. I am sure there is a much more efficient way to do this other than multiple sub selects. Any help is greatly appreciated! Thanks in advance :)

UPDATE: Basically all I am curious to find out is, is there something quicker than the multiple sub selects in the query? I am sure that there is some way to get the results from one table that do not exist in multiple other tables that is a lot more efficient than doing sub selects... The only commonality between the tables is that the ID from table_1, is identical to another column in each of the other 3 tables (which is what I am currently checking it against now using the sub selects). Unfortunately, I just cant figure out what the more efficient way to do this query is... Thanks for everyone's input thus far!

TABLE LAYOUT

mysql> show create table campaigns\G  
*************************** 1. row ***************************  
Table: campaigns  
Create Table: CREATE TABLE `campaigns` (  
`ID` int(11) NOT NULL auto_increment,  
`CreatedOn` datetime NOT NULL,  
`AddedBy` varchar(75) default NULL,  
`pCampaignName` varchar(255) default NULL,  
`CampaignName` varchar(255) default NULL,  
`CampaignValue` decimal(65,2) default '0.00',  
`CampaignPayout` decimal(65,2) NOT NULL default '0.00',  
`CampaignT` double NOT NULL default '0',  
`CampaignSD` double NOT NULL default '0',  
`ReportingTime` varchar(255) default NULL,  
`CampaignExpiration` varchar(100) default NULL,  
`DurationType` varchar(100) default NULL,  
`Countries` varchar(100) default NULL,  
`CampaignDescription` longtext,  
`CampaignRequirements` longtext,  
`CampaignType` varchar(50) default NULL,  
`CampaignID` varchar(255) default NULL,  
`BannerImageWidth` int(10) NOT NULL default '0',  
`BannerImageHeight` int(10) NOT NULL default '0',  
`BannerImageURL` varchar(255) default NULL,  
`BannerImageAlternateText` varchar(255) default NULL,  
`DisplayBanner` int(1) NOT NULL default '0',  
`CampaignCode` longtext,  
`CampaignURL` longtext,  
`CampaignActive` int(1) NOT NULL default '0',  
`Status` varchar(255) default NULL,  
`Affiliate` varchar(255) default NULL,  
`NewOfferEmailSent` int(1) unsigned NOT NULL default '0',  
`NumberApproved` double(65,2) NOT NULL default '0.00',  
`NumberLeads` double NOT NULL default '0',  
`ThumbsUp` double NOT NULL default '0',  
`ThumbsDown` double NOT NULL default '0',  
`CampaignPoints` double NOT NULL default '0',  
`UserRatingUp` double NOT NULL default '0',  
`UserRatingDown` double NOT NULL default '0',  
PRIMARY KEY  (`ID`)  
) ENGINE=MyISAM AUTO_INCREMENT=1608 DEFAULT CHARSET=utf8  
1 row in set (0.09 sec)  

mysql> show indexes from campaigns\G  
*************************** 1. row ***************************  
Table: campaigns  
Non_unique: 0  
Key_name: PRIMARY  
Seq_in_index: 1  
Column_name: ID  
Collation: A  
Cardinality: 1596  
Sub_part: NULL  
Packed: NULL  
Null:  
Index_type: BTREE  
Comment:  
1 row in set (0.10 sec)  

mysql>  
mysql> show create table acampaigns\G  
*************************** 1. row ***************************  
Table: acampaigns  
Create Table: CREATE TABLE `acampaigns` (  
`ID` int(11) NOT NULL auto_increment,  
`CreatedOn` datetime NOT NULL,  
`CampaignName` varchar(255) default NULL,  
`CampaignRequirements` longtext,  
`CampaignURL` longtext,  
`CampaignValue` decimal(65,2) NOT NULL,  
`CampaignPayout` decimal(65,2) NOT NULL,  
`CampaignReferralCommissionTier1` decimal(65,2) NOT NULL default '0.20',  
`CampaignReferralCommissionTier2` decimal(65,2) NOT NULL default '0.10',  
`CampaignT` double NOT NULL default '0',  
`CampaignSD` double NOT NULL default '0',  
`CampaignType` varchar(255) default NULL,  
`CampaignID` varchar(100) default NULL,  
`CampaignExpiration` varchar(100) default NULL,  
`CampaignReturnStatus` varchar(100) default NULL,  
`CampaignStatus` varchar(255) default NULL,  
`pCampaignID` int(11) NOT NULL,  
`pCampaignName` varchar(255) default NULL,  
`pUserID` int(11) NOT NULL,  
`pUsername` varchar(75) default NULL,  
`pUserIPAddress` varchar(30) default NULL,  
`ApprovedOn` datetime NOT NULL,  
`MarkedDone` int(1) NOT NULL default '0',  
`Notes` longtext,  
`PaidOn` datetime default NULL,  
`cBonus` decimal(65,2) NOT NULL default '0.00',  
`ReversedReason` varchar(255) default NULL,  
`CampaignPoints` double NOT NULL default '0',  
`Affiliate` varchar(255) default NULL,  
`RC1Paid` int(1) unsigned NOT NULL default '0',  
`RC2Paid` int(1) unsigned NOT NULL default '0',  
PRIMARY KEY  (`ID`)  
) ENGINE=MyISAM AUTO_INCREMENT=10996 DEFAULT CHARSET=utf8  
1 row in set (0.44 sec)  

mysql> show indexes from acampaigns\G  
*************************** 1. row ***************************  
Table: acampaigns  
Non_unique: 0  
Key_name: PRIMARY  
Seq_in_index: 1  
Column_name: ID  
Collation: A  
Cardinality: 8936  
Sub_part: NULL  
Packed: NULL  
Null:  
Index_type: BTREE  
Comment:  
1 row in set (0.09 sec)  

mysql>  
mysql> show create table bcampaigns\G  
*************************** 1. row ***************************  
Table: bcampaigns  
Create Table: CREATE TABLE `bcampaigns` (  
`ID` int(11) NOT NULL auto_increment,  
`CreatedOn` datetime NOT NULL,  
`pCampaignID` int(11) NOT NULL,  
`ReportedByUserID` int(11) NOT NULL,  
`Status` varchar(255) default NULL,  
`Notes` longtext,  
PRIMARY KEY  (`ID`)  
) ENGINE=MyISAM AUTO_INCREMENT=375 DEFAULT CHARSET=utf8  
1 row in set (0.08 sec)  

mysql> show indexes from bcampaigns\G  
*************************** 1. row ***************************  
Table: bcampaigns  
Non_unique: 0  
Key_name: PRIMARY  
Seq_in_index: 1  
Column_name: ID  
Collation: A  
Cardinality: 0  
Sub_part: NULL  
Packed: NULL  
Null:  
Index_type: BTREE  
Comment:  
1 row in set (0.08 sec)  

mysql>  
mysql> show create table icampaigns\G  
*************************** 1. row ***************************  
Table: icampaigns  
Create Table: CREATE TABLE `icampaigns` (  
`ID` int(11) NOT NULL auto_increment,  
`CreatedOn` datetime NOT NULL,  
`pCampaignID` int(11) default NULL,  
`IgnoredByUserID` int(11) default NULL,  
PRIMARY KEY  (`ID`)  
) ENGINE=MyISAM AUTO_INCREMENT=567 DEFAULT CHARSET=utf8  
1 row in set (0.09 sec)  

mysql> show indexes from icampaigns\G  
*************************** 1. row ***************************  
Table: icampaigns  
Non_unique: 0  
Key_name: PRIMARY  
Seq_in_index: 1  
Column_name: ID  
Collation: A  
Cardinality: 532  
Sub_part: NULL  
Packed: NULL  
Null:  
Index_type: BTREE  
Comment:  
1 row in set (0.40 sec)  

mysql>
mysql> explain Select ID, CreatedOn, pCampaignName, 
CampaignName, CampaignRequirements, CampaignURL, Countries, 
CampaignPayout, CampaignPoints, CampaignT, CampaignSD, CampaignType, 
ReportingTime, NumberApproved, NumberLeads
From campaigns
-> Where CampaignActive = '1' And CampaignType LIKE 'Cat%' 
And CampaignType <> 'DS' And CampaignType <> 'CC'  And CampaignType <> 'PC' 
And CampaignType <> 'PC2' And CampaignType <> 'GCC' And CampaignType <> 'G' 
And CampaignType <> 'R'
-> And ID Not In (Select pCampaignID From acampaigns  
Where campaigns.ID = acampaigns.pCampaignID And MarkedDone = '1' And campaigns.pUserID = '1')
-> And ID Not In (Select pCampaignID From bcampaigns  
Where bcampaigns.pCampaignID = campaigns.ID And  bcampaigns.ReportedByUserID = '1')
-> And ID Not In (Select pCampaignID From icampaigns  
Where icampaigns.pCampaignID = campaigns.ID And icampaigns.IgnoredByUserID = '1')
A: 

Have you tried to EXPLAIN your query. If you aren't familiar with EXPLAIN, it will produce a report showing how the query is performed and especially which indexes are used, and may show up where an index is desirable but not present.

I have also found in the past that NOT IN can sometimes be horrendously slow. Perhaps rewriting NOT IN as NOT EXISTS may speed things up.

NOT EXISTS (SELECT *
                FROM table_3
                WHERE table_3.t3ID = table_1.ID AND
                      table_3.Col1 = '1')
Brian Hooper
Changing NOT IN to NOT EXISTS seems to be about the same speed (no significant difference). Also, I EXPLAINED the query and it returned mainly NULLs. table_1 is reading just under 1,500 rows, table_2 is reading just over 7,000 rows, the other 2 tables are less than 500 rows. Everything else except the table names and select type are NULL. I tried to construct a JOIN query that will pull the same data just to see if it would be quicker, but cannot seem to get one that does not throw errors, and grabs the same data. Thanks for the help thus far!
Jay
A: 

IDFMA

please post the results of the following script so we can analyse your query in detail. if you could also pastebin the results in say http://pastie.org/ that would be great too.

thanks

show create table table_1\G
show indexes from table_1\G

show create table table_2\G
show indexes from table_2\G

show create table table_3\G
show indexes from table_3\G

show create table table_4\G
show indexes from table_4\G

explain
Select 
 ID, Col1, Col2, Col3, Col4, Col5, Col6, Col7, 
 Col8, Col9, Col10, Col11, Col12, Col13, Col14, Col15 
From 
 table_1
Where 
 Active = '1' And 
 Col2 LIKE '%Cat%' And Col3 <> 'blah' And Col3 <> 'blah1'  And Col3 <> 'blah2' And Col3 <> 'blah3' And 
 Col3 <> 'blah4' And Col3 <> 'blah5' And Col3 <> 'blah6' And 
 ID Not In (Select t2ID From table_2 Where table_2.t2ID = table_1.ID And table_2.Col1 = '1' And table_2.Col2 = '1') And 
 ID Not In (Select t3ID From table_3 Where table_3.t3ID = table_1.ID And table_3.Col1 = '1') And 
 ID Not In (Select t4ID From table_4 Where table_4.t4ID = table_1.ID And table_4.Col1 = '1');
f00
This code gave errors pointing to "show create table table_1\G" and "show indexes from table_1\G".
Jay
this might help http://pento.net/2009/02/27/the-g-modifier-in-the-mysql-command-line-client/
f00
The main post has been edited with the results you requested.
Jay
A: 

You can split this single query into multiple separate steps and put them in a single stored procedure using temporary tables. This will make it more readable and probably run faster...

Anil
This query will be ran thousands of times a day, by thousands of members which is why the optimization is needed in the first place. I may be wrong, but wouldn't splitting this query up use up even more resources on the database server?
Jay