But in the following expression:
template1=# SELECT CASE WHEN (SELECT 0)=0 THEN 0 ELSE 1/0 END;
ERROR: division by zero
(Just to be sure, a SELECT (SELECT 0)=0; returns true)
It seems that when the CASE WHEN expression is a query, the evaluation
order changes.
According to the
Stefan Drees wrote:
On 2013-06-17 22:17 +02:00, Andrea Lombardoni wrote:
I observed the following behaviour (I tested the following statements in
9.0.4, 9.0.5 and 9.3beta1):
$ psql template1
template1=# SELECT CASE WHEN 0=0 THEN 0 ELSE 1/0 END;
case
--
0
(1 row)
template1=#
On Mon, Jun 17, 2013 at 11:11 PM, Stefan Drees ste...@drees.name wrote:
pg924=# SELECT CASE WHEN 1 != 1 THEN 1/0 ELSE ((SELECT 1)=1)::integer END;
case
--
1
(1 row)
here the 1/0 is happily ignored.
It gets even stranger:
template1=# SELECT CASE WHEN (SELECT 0)=0 THEN 0 ELSE
Andrea Lombardoni wrote:
It gets even stranger:
template1=# SELECT CASE WHEN (SELECT 0)=0 THEN 0 ELSE 1/(select 0) END;
case
--
0
(1 row)
Here it seems that the ELSE does not get evaluated (which is correct).
Yes, of course, because both subselects will not get evaluated at
I observed the following behaviour (I tested the following statements in
9.0.4, 9.0.5 and 9.3beta1):
$ psql template1
template1=# SELECT CASE WHEN 0=0 THEN 0 ELSE 1/0 END;
case
--
0
(1 row)
template1=# SELECT CASE WHEN 1=0 THEN 0 ELSE 1/0 END;
ERROR: division by zero
In this case the
On 2013-06-17 22:17 +02:00, Andrea Lombardoni wrote:
I observed the following behaviour (I tested the following statements in
9.0.4, 9.0.5 and 9.3beta1):
$ psql template1
template1=# SELECT CASE WHEN 0=0 THEN 0 ELSE 1/0 END;
case
--
0
(1 row)
template1=# SELECT CASE WHEN 1=0 THEN 0
