Bad error message

On Wed, Oct 1, 2008 at 3:07 AM, Decibel! <decibel@decibel.org> wrote:

From -HEAD:

ERROR: aggregates not allowed in WHERE clause
STATEMENT: SELECT *
FROM loans l
WHERE id IN ( SELECT max(l.id)
FROM loans
JOIN customers c ON c.id =
l.customer_id
JOIN people p ON p.id = c.person_id
WHERE p.first_name = 'Test person'
GROUP BY l.loan_type_cd
)
;

The real issue is this:

ERROR: missing FROM-clause entry for table "l" at character 132
STATEMENT: SELECT max(l.id)
FROM loans
JOIN customers c ON c.id =
l.customer_id
JOIN people p ON p.id =
c.person_id
WHERE p.first_name = 'Test
person'
GROUP BY l.loan_type_cd;

And if I change the FROM loans to be FROM loans l, the original select does
work fine.

Let me know if I need to create a full test case for this...

No, the real issue is that you are referencing the outer table's column's
max() in the inner query (correlated sub-query). The table in the outer
query is aliased 'l' and the sub-query is trying to aggregate that, which is
in the outer query's WHERE clause; and that is not allowed.

Renaming the outer query's alias to something other than 'l' would show you
the real error (which again would be 'missing FROM-clause entry).

Best regards,
--
gurjeet[.singh]@EnterpriseDB.com
singh.gurjeet@{ gmail | hotmail | indiatimes | yahoo }.com

EnterpriseDB http://www.enterprisedb.com

Mail sent from my BlackLaptop device

"Gurjeet Singh" <singh.gurjeet@gmail.com> writes:

On Wed, Oct 1, 2008 at 3:07 AM, Decibel! <decibel@decibel.org> wrote:

ERROR: aggregates not allowed in WHERE clause

No, the real issue is that you are referencing the outer table's column's
max() in the inner query (correlated sub-query).

Yeah. It's not easy to see how the software could guess your real
intentions here. We could maybe offer a vaguely-worded HINT but I'm
not able to think of wording that would be very helpful.

regards, tom lane

On Wed, Oct 1, 2008 at 9:39 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

"Gurjeet Singh" <singh.gurjeet@gmail.com> writes:

On Wed, Oct 1, 2008 at 3:07 AM, Decibel! <decibel@decibel.org> wrote:

ERROR: aggregates not allowed in WHERE clause

No, the real issue is that you are referencing the outer table's column's
max() in the inner query (correlated sub-query).

Yeah. It's not easy to see how the software could guess your real
intentions here. We could maybe offer a vaguely-worded HINT but I'm
not able to think of wording that would be very helpful.

Can we do something like this in the code:

if( "level of the referenced column's relation" != "level of the
(sub)query being processed" )
errhint( "The subquery may be unintentionally referencing an outer
query's column!" );

Best regards,
--
gurjeet[.singh]@EnterpriseDB.com
singh.gurjeet@{ gmail | hotmail | indiatimes | yahoo }.com

EnterpriseDB http://www.enterprisedb.com

Mail sent from my BlackLaptop device

On Oct 1, 2008, at 12:12 AM, Gurjeet Singh wrote:

On Wed, Oct 1, 2008 at 9:39 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
"Gurjeet Singh" <singh.gurjeet@gmail.com> writes:

On Wed, Oct 1, 2008 at 3:07 AM, Decibel! <decibel@decibel.org>

wrote:

ERROR: aggregates not allowed in WHERE clause

No, the real issue is that you are referencing the outer table's

column's

max() in the inner query (correlated sub-query).

Yeah. It's not easy to see how the software could guess your real
intentions here. We could maybe offer a vaguely-worded HINT but I'm
not able to think of wording that would be very helpful.

Can we do something like this in the code:

if( "level of the referenced column's relation" != "level of
the (sub)query being processed" )
errhint( "The subquery may be unintentionally referencing
an outer query's column!" );

Yeah, something like that would be very helpful.

Mail sent from my BlackLaptop device

Haha. +1
--
Decibel!, aka Jim C. Nasby, Database Architect decibel@decibel.org
Give your computer some brain candy! www.distributed.net Team #1828