Re: [COMMITTERS] 'pgsql/src/backend/parser gram.y'

> Bruce Momjian <maillist@candle.pha.pa.us> writes:
> >> Repair recently-introduced error in makeIndexable for LIKE:
> >> a non-leading % would be put into the >=/<= patterns.  Also, repair
> >> longstanding confusion about whether %% means a literal %%.  The SQL92
> >> doesn't say any such thing, and textlike() knows that, but gram.y didn't.
> 
> > Houston, we have a problem.  DoMatch has:
> 
> >             case '%':
> >                 /* %% is the same as % according to the SQL standard */
> >                 /* Advance past all %'s */
> >                 while (*p == '%')
> 
> > Don't we want %% to be %?
> 
> I looked at the spec, and this piece of code is right: there is nothing
> in the spec that says that %% means anything other than two string
> pattern matches (which of course has the same effect as one).  So I made
> gram.y agree.
> 
> It could be that people like Microsoft don't follow the spec... can
> anyone check this?

DoMatch, which implements LIKE clearly thinks %% is %, and I think our
users think so too.  I would not change it.

--  Bruce Momjian                        |  http://www.op.net/~candle maillist@candle.pha.pa.us            |  (610)
853-3000+  If your life is a hard drive,     |  830 Blythe Avenue +  Christ can be your backup.        |  Drexel Hill,
Pennsylvania19026