Re: Parameterized prepared statements

Hey Craig,

Things like pre-parsed prepared statements that're re-planned on every
> execution are often proposed as solutions to this. This has me wondering:
> rather than expensively re-planning from scratch, would it be possiblet to
> adjust the planning process so that *multiple* alternative plans would be
> cached for a query, using placeholders for unknown rowcounts and costs? At
> execution, the unknown costs would be filled in and the plans compared then
> the best plan picked for this execution. Is this crazy talk, or could it
> significantly reduce the cost of re-planning parameterized prepared
> statements to the point where it'd be worth doing by default?
>
Its a good suggestion of some kind of optimization at the server side.
This idea can be extended to an "auto-prepare" mode (like an auto-commit
mode that we have today in Postgres).
But its not so hard to let the application (or library) to decide what to
use in
different cases: prepared statement or regular statement. Thus, I think it
is
not worth it...

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> Craig Ringer
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// Dmitriy.