Re: BUG #4436: (E'\\' LIKE E'\\') => f

Tom Lane wrote:
> Bruce Momjian  writes:
> > Mathieu Fenniak wrote:
> >> I noticed that (SELECT E'\\' LIKE E'\\') returns false,
> 
> > I believe this is caused because backslash is the default escape
> > character for LIKE, so you need:
> > 	test=> SELECT E'\\' LIKE E'\\\\';
> 
> Yeah.  The given case is actually an invalid LIKE pattern.  I wonder
> whether we should make LIKE throw error for an invalid pattern.
> You get an error for the corresponding case in regex:
> 
> regression=# select E'\\' ~ E'\\';
> ERROR:  invalid regular expression: invalid escape \ sequence
> 
> but IIRC the LIKE code just silently ignores a trailing escape
> character.

Yes, I think we should throw an error;  the original query looked odd to
me too.

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  Bruce Momjian          http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

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