Re: [HACKERS] Bug in LIKE ?

Thomas Lockhart <lockhart@alumni.caltech.edu> writes:
>> Anyway, it's fixed now.  I also cleaned up some confusion about whether
>> "%%" in a LIKE pattern means a literal % (the SQL spec says not, and
>> some parts of the code knew it, but other parts didn't...)

> Yeah, but until we have support for the ESCAPE clause on the LIKE
> expression then there isn't a way to get a literal "%" into the query
> :( 

Sure there is: \%.  Of course, defaulting to ESCAPE \ rather than no
escape is not standards-compliant either, but it's a lot closer than
inventing a meaning for %% ...

More to the point, %% has not worked like gram.y thought it did for
a long time, if ever, and no one's complained ...

> imho we will eventually need to move all of this out of gram.y and put
> it deeper into the parser code, since it is munging the query so early
> it is difficult to know what was done for later stages.

Agreed.  At the very least it should be postponed until we know that the
operator in question *is* textlike(), and not something else that
happens to be named ~~ ... but that's a job for another day.
        regards, tom lane