On 9/17/14, 9:00 PM, Peter Eisentraut wrote:
> On 9/14/14 2:49 PM, Jan Wieck wrote:
>> I don't think it is even a good idea to implement assertions that can
>> query arbitrary data.
>
> In a normal programming language, an assertion is usually a static fault
> in your program. If the assertion ever fails, you fix your program and
> then it hopefully never happens again.
>
> Assertion that query the state of the database or result row counts are
> pushing that concept quite a bit. Those are not assertions, those are
> just plain old error handling.
*shrug* I don't see them as error handling if they're just checking
conditions which should never happen.
That said, in PL/PgSQL these expressions would likely have to be SQL
expressions, and then you'd have to go out of your way to implement
assertions which *can't* query arbitrary data. And that just seems silly.
.marko