Re: Needless additional partition check in INSERT?

On 2018-Jun-07, David Rowley wrote:

> On 7 June 2018 at 15:57, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
> > Hm I was thinking this new function would be companion to ExecConstrains
> > (a fact I used in the name I proposed,) so it'd be in the same file
> > (probably right after it.)
> 
> Okay. v5 (attached) does it that way.

Thanks, looks nice (function name is stupidly long, my fault).

I wondered about the refactoring that Amit Khandekar is proposing.
Given the improved API you gave the new function, it appears we can
write it like this (untested):

bool
ExecConstraintsPartConstrNeedsRecheck(ResultRelInfo *resultRelInfo,
        bool tupleRouting)
{
    if (tupleRouting)
    {
        if (resultRelInfo->ri_TrigDesc &&
            resultRelInfo->ri_TrigDesc->trig_insert_before_row)
            return true;
    }
    else if (resultRelInfo->ri_PartitionCheck != NIL)
        return true;

    return false;    /* no need to recheck */
}

I was also wondering about introducing a new function call in this path
where previously was none.  Given the amount of other stuff that's
happening when a tuple is inserted, I suppose it's not worth worrying
about in terms of making this an inline function in the header.

BTW I noticed that ExecConstraints() indicates that the given
resultRelInfo is "the original resultRelInfo, before tuple routing", but
that's demostrably false.  What's up with that?

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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