"fbsd_user" <[EMAIL PROTECTED]> wrote on 03/13/2006 01:10:17 PM:
> In my mysql 4.4 table definition the default attributes are (ON > UPDATE CURRENT_TIMESTAMP). Reading the manual my understanding is > this is saying that the auto timestamp update feature is active. The > manual does not say what the trigger is to make the timestamp in the > row to be bumped to the current timestamp. I have noticed that the > timestamp field is only bumped when I update a field in the row. I > would like it to be auto bumped every time the row is selected/read. > Is there a way to do this without creating a timestamp from date in > my php code and then updating the row instead of reading the row? > The final goal is to auto bump the timestamp every time the user > logs on. > It sounds like there is a logon process that the user must perform. What's the issue you have about updating your timestamp from within that process? That's where it sounds most logical to me to add the code to bump your timestamp value. >From a design point of view, it would seriously slow down the entire server if it had to check for something to do on EVERY read from ANY table. In order to do what you want the database to do, that facility would need to exist so that the engine could bump the timestamp automatically. It is generally much better to NOT write SELECT statements to a log or to do anything else that would slow them down. Checking every row that ever got selected to see if any column in it is an auto-update-on-select-timestamp column would do that in a major way. It also breaks all kinds of SQL rules to make a SELECT clause into something that modifies data. That would lead to all sorts of data chaos and I want no part of it. I am sorry, but if you want the timestamp changed you are going to have to initiate that change by an UPDATE statement. Shawn Green Database Administrator Unimin Corporation - Spruce Pine
