----- Original Message ----- From: "Chip Wiegand" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, August 17, 2004 12:29 PM Subject: I can delete, add, but not update
> I don't know for sure, but I think I may have something wrong with > permissions in MySQL. I have some web forms from which I can add new data > and delete data. But when I try to do an update of existing data the data > is not actually changed. Is it possible that the permissions are not set > up correctly in MySQL? Sure it's possible. But it's also possible that your update statements are written incorrectly, in such a way that they compile okay but don't actually touch the rows you want to update. For example, if your UPDATE wants to give raises to the people in department D21, this query won't do it: update employees set salary = salary * 2 where dept = 'D22' [Please don't take offence: I'm not suggesting that you would miss anything this obvious. I'm only trying to present a very simple example that illustrates my point.] It is also possible that your updates are written correctly but that no qualifying rows are available to update. For example, if you correct the UPDATE above but don't actually have any employees in department D21 at the moment, the UPDATE will fail to change anything. [Again, you would probably catch an error that obvious. However, the WHERE clause in your UPDATE could be much more complex and it would be easy to mess it up in such a way that it didn't hit the rows that you meant to update. All you'd need to do was misspell a word or spell it with the wrong case, use 'NOT' in front of an operator that was supposed to be positive, or whatever and you would have a problem.] Another possibility, somewhat less likely than the others, is that you are looking at the rows that were supposed to be updated before they were committed. In other words, if you do an update, and look at the result before the COMMIT has taken place, you may be seeing the old version of the data. Make sure that you have done the COMMIT before attempting to look at the changed data. By all means look at the syntax for the GRANT command in the MySQL manual and make sure you have set the UPDATE privileges appropriately for your table. Be sure to check out these other things if the GRANT command doesn't appear to be the problem. Rhino -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
