Hello all,
I have a query that presents a sum() where in some records it's NULL
because all members of the group are NULL.
I decided I wanted to see a pretty 0 instead of NULL since it fits the
logic of the app.
This didn't work as expected (the NULL's persisted):
...CASE sum(foo) WHEN NULL THEN 0 ELSE sum(foo) END...
Whereas changing it to:
...CASE WHEN sum(foo) IS NULL THEN 0 ELSE sum(foo) END...
it works as expected, substituting the sum()'s that are NULL to zeros.
Is that expected behavior? Do i misunderstand how CASE/WHEN works?
Running: PostgreSQL 9.1.3 on i686-pc-linux-gnu, compiled by gcc (GCC)
3.4.6, 32-bit
TIA,
Thalis K.