Re: pgsql-server/ oc/src/sgml/runtime.sgml rc/back ...

> Log message:
>     Finish implementation of hashed aggregation.  Add enable_hashagg GUC
>     parameter to allow it to be forced off for comparison purposes.
>     Add ORDER BY clauses to a bunch of regression test queries that will
>     otherwise produce randomly-ordered output in the new regime.

Out of interest (since I was away while this was proposed I assume),
what's the idea with hashed aggergation?  I assume each group is now in a
hash bucket?  How did it work before?

Chris