"David Parker" <dparker@xxxxxxxxxxxxxxxx> writes: > I know from the documentation that the FOR implicitly opens a cursor, > but I'm wondering if there would be any performance advantages to > explicitly declaring a cursor and moving through it with FETCH commands? AFAICS it'd be exactly the same. Might as well stick with the simpler notation. > I have to use the ORDER BY, so I imagine I'm taking the hit of > processing all the records in the table anyway, regardless of how many I > ultimately fetch. Not if the ORDER BY can be implemented using an index. Perhaps what you need is to make sure that an indexscan gets used. > The nature of the data is that chunksize doesn't necessarily match up > one-for-one with rows, so I can't use it as a LIMIT value. Can you set an upper bound on how many rows you need? If you can put a LIMIT into the select, it'll encourage the planner to use an indexscan, even if you break out of the loop before the limit is reached. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
