Re: [HACKERS] RE: [GENERAL] Long update query ? (also Re: [GENERAL] CNF vs. DNF)

> The problem is that you cannot depend upon factoring to reduce these complex
> statements.   We need to retain a place holder (pointer) for each passed
> parameter.   Otherwise we need to re-(parse and plan) the statement before each
> execution; thus, loosing one of the major benefits of PREPARE.

I think we already have such a problem.  When using optimization
statistics, the optimizer checks the value of the constant to determine
how many rows will be returned by a "x > 10" by looking at the min/max
values for the column.  Prepared queries where this value will change
would make that a problem.



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