Ben <bench(at)silentmedia(dot)com> writes:
> Unfortunately, it's not at all clear to me from reading
> http://www.postgresql.org/docs/8.1/interactive/xoper-optimization.html#AEN33077
> how like impliments selectivity. Any pointers on where to look?
likesel() and subsidiary functions in src/backend/utils/adt/selfuncs.c
regards, tom lane