Question

I am trying to run a replace into DB call, but I only want it to execute if the supplied printerid# is greater then the database stored printerid#.

Here is my example code which hopefully makes sense of this

unitid = 2382;
printerid = 9826;

REPLACE INTO devices (unitid, printerid)
VALUES ('"+ unitid +"', '"+ printerid +"')
WHILE '"+printerid+"' > devices.printerid

So for example, if the devices database already has an entry for unitid 2382 that has a printer ID of 9999, then the SQL call should do nothing, but if it had a printer ID of 8888 it would replace it with my new printer ID of 9826.

The above listed SQL code doesn’t work though obviously. 🙁

Thanks!

Answer 1

You could also use INSERT INTO ... ON DUPLICATE KEY assuming you have a primary/unique key on unitid:

INSERT INTO devices (unitid, printerid)
VALUES ('"+ unitid +"', '"+ printerid +"')
ON DUPLICATE KEY UPDATE devices
SET unitid = '"+ unitid +"', printerid = '"+ printerid +"'
WHERE unitid = '"+ unitid +"' AND printerid < '"+ printerid +"'