Hi all. I have a problem understanding/using PostgreSQL as a multiuser database. I have a simple table with a number of different IDs (int8) used for different activities. It should be possible for any number of simultaneous users to receive a unique ID for a particular activity and then update these IDs. I thought this would be the way to go: --- set transaction isolation level serializable; begin work; select val from ids where cntr='ct1' for update; update ids set val=val+(some integer value) where cntr='ct1'; commit work; --- However, when I run everything except the commit on one terminal and then run up to and including the select on another terminal, I receive the OLD, non-updated value for val on that second terminal. In other words, the select is not blocked and the id is not unique. Not what I intended at all! What gives? Does anybody know how to do this in PostgreSQL? Al. ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])