Mysql: Insert or Update in One SQL Statement

I must say, I really wish I knew about this technique years ago – before I started using frameworks to do a lot of my development.  The effort that was wasted in building separate code and separate logic to deal with inserts vs updates, when all of this time, there is a nice and simple feature built-in to Mysql that does this for us…

 The process is quite straight forward, when I run a standard INSERT statement with Mysql, I can provide additional properties for dealing with DUPLICATE KEY, e.g. the record already exists.

Here is an example:

[code]
INSERT INTO `table` (`name`, `created`, `modified`)
VALUES (‘Jamie’, NOW(), NOW())
ON DUPLICATE KEY
UPDATE `name` = ‘Jamie’, `modified` = NOW()
[/code]

Notice how in the UPDATE statement I’m only updating the name and modified date.

Another nice example can be used for keeping track of the number of times a tag is used.  Imagine you have a table with a list of tags and their associated count.  You can leverage the above functionality to increase the count each time the tag is used again:

[code]
INSERT INTO `tags` (`tag`, `count`, `created`, `modified`)
VALUES (‘mysql’, 1, NOW(), NOW())
ON DUPLICATE KEY
UPDATE `count` = `count` + 1, `modified` = NOW()
[/code]

That’s it!  No more need to right functionality like:

[code]
if ($id == 0) {
// do insert
} else {
// do update
}
[/code]

For my information, visit Mysql Documentation.