Re: like/ilike improvements

Tom Lane wrote:
> OK, I studied it a bit more and now see what you're driving at: in this
> form of the patch, we treat % bytewise unless it is followed by _, in
> which case we treat it char-wise. That seems a good tradeoff,
> considering that such a pattern is probably pretty uncommon --- we
> should be willing to handle it a bit slower to simplify other cases.
>
> The patch seems still not right though, because you are advancing by
> bytes when \ follows %, and that isn't correct in a non-UTF8 encoding.
> The invariant we are actually insisting on here is that at the time of
> entry to MatchText(), whether initial or recursive, t and p must be
> correctly char-aligned. I suggest the attached revision of the logic as
> a way to clarify that, and maybe save a cycle or two in the inner loop
> as well.
>

Good, thanks.
> Yes, I concur we needn't bother with IsFirstByte except maybe as an
> Assert. If it is an Assert it should be up at the top of the function.
>
>

Looks like emails crossed. Glad we're on the same page. I'm away for a
few days, so I'll attend to this next week.

cheers

andrew