Re: Possible bug in CASE evaluation

On 2013-06-21 16:45:28 +0200, Andres Freund wrote:
> On 2013-06-21 09:51:05 -0400, Noah Misch wrote:
> > That being said, if we discover a simple-enough fix that performs well, we may
> > as well incorporate it.
>
> What about passing another parameter down eval_const_expressions_mutator
> (which is static, so changing the API isn't a problem) that basically
> tells us whether we actually should evaluate expressions or just perform
> the transformation?
> There's seems to be basically a couple of places where we call dangerous
> things:
> * simplify_function (via ->evaluate_function->evaluate_expr) which is
>   called in a bunch of places
> * evaluate_expr which is directly called in T_ArrayExpr
>   T_ArrayCoerceExpr
>
> All places I've inspected so far need to deal with simplify_function
> returning NULL anyway, so that seems like a viable fix.

*Prototype* patch - that seems simple enough - attached. Opinions?

Greetings,

Andres Freund

--
 Andres Freund                       http://www.2ndQuadrant.com/
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