Re: Possible bug in CASE evaluation

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.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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