Suppose I have the following table named "metrics":
metric_type | val
------------+-----
0 | 1
0 | 1
1 | 0
1 | 3
Now suppose I run the following simple query:
select
metric_type,
case metric_type
when 0 then
sum (1 / val)
when 1 then
sum (val)
end as result
from metrics
group by metric_type
I expect to get the following result set:
metric_type | result
------------+-------
0 | 2
1 | 3
But in reality I get the following error:
ERROR: division by zero
SQL state: 22012
So it appears that Postgres executes all cases and select the result in
the end. Is this expected behavior?
Thanks
- Jimmy
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