Question

Im running a database log and every day I log on a new row. My Mysql query therefore checks if the day (date (the unique key)) already exists, and if so, it tries to increment all the loggable values of the log-row by one. If the date record doesnt eyist yet, it will create a new row.

My SQL query is:

INSERT INTO `log` (`date`,`hits`,`stale`)
VALUES ('2012-03-06',1,1)   
ON DUPLICATE KEY
UPDATE `hits`=`hits`+1,`stale`=`stale`+1
WHERE `date`='2012-03-06';"

All columns have 0 as default value, so if this query runs directly after midnight only ‘stale’ and ‘hits’ are set to 1. Otherwise ‘stale’ and ‘hits’ are both incremented.

I wish! (it doesn’t work).

What am I missing? Which separator other then a comma should I use between ‘hits’ = ‘hits’ +1 and ‘stale’=’stale’+1?

Answer 1

You shouldn’t have the WHERE clause. ON DUPLICATE KEY UPDATE automatically limits the row it affects to the one that has the existing key.

Remove it and your query should work fine.