Question

I have a table that its structure is as like as follow:

`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`ttype` int(1) DEFAULT '19',
`title` mediumtext,
`tcode` char(2) DEFAULT NULL,
`tdate` int(11) DEFAULT NULL,
`visit` int(11) DEFAULT '0',
PRIMARY KEY (`id`),
KEY `tcode` (`tcode`),
KEY `ttype` (`ttype`),
KEY `tdate` (`tdate`)


ENGINE=MyISAM 

I have two query on x.php same as:

SELECT * FROM table_name WHERE id='10' LIMIT 1
UPDATE  table_name SET visit=visit+1 WHERE id='10' LIMIT 1

My first problem is that whether updating ‘visit’ in table cause reindexing and decreasing performance or not? Note to this point that ‘visit’ is not key.

Second method may be creating new table that contain ‘visit’ like as follow:

'newid' int(10)  unsigned NOT NULL ,
`visit` int(11) DEFAULT '0',
 PRIMARY KEY (`newid`),

     ENGINE=MyISAM 

So selecting by

SELECT w.*,q.visit FROM table_name w  LEFT JOIN table_name2 q 
ON (w.id=q.newid) WHERE w.id='10' LIMIT 1 

    UPDATE  table_name2 SET visit=visit+1 WHERE newid='10' LIMIT 1

Is second method prefered rescpect to first method? Which one would have better performance and would be quick?

Note: all sql queries would be run by PHP (mysql_query command). Also I need first table indexes for other queries on other pages.

Answer 1

I’d say your first method is the best, and simplest. Updating visit will be very fast and no updating of indexes needs to be performed.

I’d prefer the first, and have used that for similar things in the past with no problems. You can remove the limit clause since id is your primary key you will never have more than 1 result, although the query optimizer probably does this for you.