Re: Aggregate Push Down - Performing aggregation on foreign server

On Mon, Sep 12, 2016 at 12:20 PM, Prabhat Sahu <prabhat.sahu@enterprisedb.com> wrote:

Hi,

While testing "Aggregate pushdown", i found the below error:
-- GROUP BY alias showing different behavior after adding patch.

-- Create table "t1", insert few records.
create table t1(c1 int);
insert into t1 values(10), (20);

-- Create foreign table:
create foreign table f_t1 (c1 int) server db1_server options (table_name 't1');

-- with local table:
postgres=# select 2 a, avg(c1) from t1 group by a;
 a |         avg        
---+---------------------
 2 | 15.0000000000000000
(1 row)

-- with foreign table:
postgres=# select 2 a, avg(c1) from f_t1 group by a;
ERROR:  aggregate functions are not allowed in GROUP BY
CONTEXT:  Remote SQL command: EXPLAIN SELECT 2, avg(c1) FROM public.t1 GROUP BY 2

Thanks for reporting this bug in *v1.patch Prabhat.

I will have a look over this issue and will post a fix in next version.