Hi all. I need to keep a numer of counters in my application; my counters are currently stored in a table: name | next_value | year The counters must be progressive numbers with no holes in between them, and they must restart from 1 every year. What I've done so far is to access them while in SERIALIZABLE ISOLATION LEVEL, with the following: SELECT next_value FROM counters WHERE name = 'name' for update; UPDATE counters SET next_value = next_value + 1 WHERE name = 'name'; of course, if I do not find the counter, I create it (which automatically happens at the begin of a new year). This seems to work to me, but I've two questions: 1) is there any scenario which I'm missing here and which could lead me to troubles? Deadlocks excluded. 2) while this works, it has the unfortunate behaviour to cause conflict between concurrent transactions; so, one of them has to be restarted and redone from scratch. Is there a way to avoid this behaviour? maybe with lock to tables? Thanks you all for your attention Regards Marco -- Marco Bizzarri http://iliveinpisa.blogspot.com/
