Re: \if, \elseif, \else, \endif (was Re: PSQL commands: \quit_if, \quit_unless) - Mailing list pgsql-hackers

From Tom Lane
Subject Re: \if, \elseif, \else, \endif (was Re: PSQL commands: \quit_if, \quit_unless)
Date
Msg-id 18081.1490888751@sss.pgh.pa.us
Whole thread Raw
In response to Re: \if, \elseif, \else, \endif (was Re: PSQL commands:\quit_if, \quit_unless)  (Fabien COELHO <coelho@cri.ensmp.fr>)
List pgsql-hackers
Fabien COELHO <coelho@cri.ensmp.fr> writes:
>> [...] Aside from cosmetic changes, I've made it behave reasonably for 
>> cases where \if is used on portions of a query, for instance

> A small issue I see is that I was planning to add such an if syntax to 
> pgbench (well, at least if I succeed in getting boolean expressions and 
> setting variables, which is just a maybe), but this kind of if in the 
> middle of expression does not make much sense for a pgbench script where 
> "if" must be evaluated at execution time, not parse time.

Well, it's not really clear to me why that would be true.  If it actually
is impossible to give pgbench equivalent behavior, we'll just have to live
with the discrepancy, but ISTM it could probably be made to work.
        regards, tom lane



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