Simon Riggs <simon@xxxxxxxxxxxxxxx> writes: > On Mon, 2005-05-09 at 12:21 -0500, Kris Kiger wrote: >> Quick question. I lock a table, call it table X, and then issue two >> updates on that table. The two updates are left waiting. I then unlock >> the table. The two updates go through. My question is, is there a >> predictable way to determine which query will be executed first? > The lock queue is served in FIFO sequence. ... usually. We will promote later arrivals in front of older ones if the alternative would be a deadlock (eg, the later one already holds some lock that would block the earlier one). regards, tom lane
