Re-added to open items:
Fix SIMILAR TO to be ANSI compliant or remove it (Peter, Tom) --------------------------------------------------------------------------- Tom Lane wrote: > "Marc G. Fournier" <[EMAIL PROTECTED]> writes: > > I'm in agreement with Thomas here ... unless a problem has been defined a > > bit more specifically then 'it isn't posix compliant', it shouldn't be > > considered an open item ... please remove? > > A quick review of SQL99 says that their notion of SIMILAR TO patterns > is an unholy witches' brew: it does *both* common-or-garden regexp > expressions and LIKE patterns. Specifically, I see these > metacharacters: > > | OR (regexp-ish) > > * repeat 0 or more times (regexp-ish) > > + repeat 1 or more times (regexp-ish) > > % match any character sequence (like LIKE) > > _ match any one character (like LIKE) > > [...] almost-but-not-quite-regexp-ish character class > > (...) grouping (regexp-ish) > > plus a just-like-LIKE treatment of a selectable escape character. > > But the most important variation from common regex practice is that > (if I'm reading the spec correctly) the pattern must match to the > entire target string --- ie, it's effectively both left- and right- > anchored. This is like LIKE patterns but utterly unlike common regexp > usage. > > I could live with the fact that our regexp patterns don't implement all > of the spec-mandated metacharacters. But I do not think we can ignore > the difference in anchoring behavior. This is not a subset of the spec > behavior, it is just plain wrong. > > I vote with Peter: we fix this or we disable it before 7.3 release. > It is not anywhere near spec compliant, and we will be doing no one > a favor by releasing it in the current state. > > regards, tom lane > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Don't 'kill -9' the postmaster > -- Bruce Momjian | http://candle.pha.pa.us [EMAIL PROTECTED] | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073 ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly