BUG #4780: Aggregate functions are unaware of LIMIT clauses in SELECTs

The following bug has been logged online:

Bug reference:      4780
Logged by:          Ted Holzman
Email address:      tholzman@fhcrc.org
PostgreSQL version: 8.3.7
Operating system:   SuSE Linux 10.3
Description:        Aggregate functions are unaware of LIMIT clauses in
SELECTs
Details:

Hi,

I don't know if this is a bug or an arcane feature, but AGGREGATE functions
don't appear to respond to LIMIT clauses.  For example:

The untouched results of a query.

experiments=# select generate_series from generate_series(1,10);
 generate_series
-----------------
               1
               2
               3
               4
               5
               6
               7
               8
               9
              10
(10 rows)


The LIMITed results of a query.

experiments=# select generate_series from generate_series(1,10) limit 3;
 generate_series
-----------------
               1
               2
               3
(3 rows)


The SUM (aggregated) results of a limited query:


experiments=# select sum(genera
te_series) from generate_series(1,10) limit 3;
 sum
-----
  55
(1 row)

I was expecting the sum to be 6.

              ==Ted