pgsql: Doc: Remove obsolete CREATE AGGREGATE note.

Doc: Remove obsolete CREATE AGGREGATE note.

The planner is in fact willing to use hash aggregation when work_mem is
not set high enough for everything to fit in memory. This has been the
case since commit 1f39bce0, which added disk-based hash aggregation.

There are a few remaining cases in which hash aggregation is avoided as
a matter of policy when the planner surmises that spilling will be
necessary. For example, callers of choose_hashed_setop() still
conservatively avoid hash aggregation when spilling is anticipated.
That doesn't seem like a good enough reason to mention hash aggregation
in this context.

Backpatch: 13-, where disk-based hash aggregation was introduced.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f36e82072c8866ba2eca08d88d1a5c3e0c3d1eb4

Modified Files
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doc/src/sgml/ref/create_aggregate.sgml | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)