On Wednesday 25 June 2003 20:06, Reuben D. Budiardja wrote: > Hi, > I am developing application with PHP as the front end, PGSQL as the > backend. I am trying to figure out what's the best way to do this. > I want to check if an entry already exists in the table. If it does, then I > will do > UPDATE tablename .... > > otherwise, I will do > INSER INTO tablename... (...)
> I vaguely remember in Oracle, there is something like this: > > INSERT INTO mytable > SELECT 'value1', 'value2' > FROM dummy_table > WHERE NOT EXISTS > (SELECT NULL FROM mytable > WHERE mycondition) > > This query will do INSERT, if there is not an entry already in the TABLE > mytable that match the condition mycondition. Otherwise, the INSERT just > fails and return 0 (without returning error), so I can check on that and do > update instead. This kind of query should work; just leave out the "FROM dummy_table" bit. (in Oracle it would be "FROM dual"). Ian Barwick [EMAIL PROTECTED] ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
