Thread: SIMILAR TO
SIMILAR TO doesn't implement the SQL standard, it's only a wrapper around the POSIX regexp matching, which is wrong. I thought someone wanted to fix that, but if it's not happening it should be removed. -- Peter Eisentraut peter_e@gmx.net
> SIMILAR TO doesn't implement the SQL standard, it's only a wrapper around
> the POSIX regexp matching, which is wrong. I thought someone wanted to
> fix that, but if it's not happening it should be removed.
Please be specific on what you would consider correct. I'm not recalling
any details of past discussions so need some background.
I see mention in my SQL99 docs of escape characters for "similar
pattern" which would suggest that it resembles Posix regexp matching. I
don't have the code in front of me to check on the details of the
current implementation, but I'd hope that you have something helpful to
say on what a better implementation would be.
Regards.
- Tom
Thomas Lockhart writes: > > SIMILAR TO doesn't implement the SQL standard, it's only a wrapper around > > the POSIX regexp matching, which is wrong. I thought someone wanted to > > fix that, but if it's not happening it should be removed. > > Please be specific on what you would consider correct. I'm not recalling > any details of past discussions so need some background. The pattern that should be accepted by SIMILAR TO (as defined in SQL99 part 2 clause 8.6) and the POSIX regular expressions that it accepts now are not the same. -- Peter Eisentraut peter_e@gmx.net
Is this a TODO? --------------------------------------------------------------------------- Peter Eisentraut wrote: > Thomas Lockhart writes: > > > > SIMILAR TO doesn't implement the SQL standard, it's only a wrapper around > > > the POSIX regexp matching, which is wrong. I thought someone wanted to > > > fix that, but if it's not happening it should be removed. > > > > Please be specific on what you would consider correct. I'm not recalling > > any details of past discussions so need some background. > > The pattern that should be accepted by SIMILAR TO (as defined in SQL99 > part 2 clause 8.6) and the POSIX regular expressions that it accepts now > are not the same. > > -- > Peter Eisentraut peter_e@gmx.net > > > ---------------------------(end of broadcast)--------------------------- > TIP 1: subscribe and unsubscribe commands go to majordomo@postgresql.org > -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
Bruce Momjian writes: > Is this a TODO? It's a must-fix for 7.3, but frankly I don't see how we could justify making the required extensive changes during beta. I suggest that we keep the parser support and throw an error when it's invoked. -- Peter Eisentraut peter_e@gmx.net