Re: cursors outside transactions

Tom Lane wrote:
> Dave Cramer <Dave(at)micro-automation(dot)net> writes:
> > On Tue, 2003-03-18 at 19:00, Hiroshi Inoue wrote:
> >> ODBC(maybe JDBC also) has cross-transaction result sets
> >> (rather than cursors) since long by simply holding all
> >> results for a query at client side.
>
> > JDBC is running into problems with this. Large queries cause out of
> > memory exceptions.
>
> Cursors implemented as Neil suggests would cause out-of-disk exceptions.
> The limit is presumably further away than out-of-memory, but not any the
> less real. I'm concerned about this because, in my mind, one of the
> principal uses of cursors is to deal with too-huge-to-materialize result
> sets.

I don't see how you can class out of memory in the same likelyhood as
out of disk --- sure they are both real possible failures, but clearly
the latter is more rare and giving folks backing store for large result
sets is a big win in my book.

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