Re: regexp_replace behavior

Marcin Krawczyk escribió:

> Hi list,
>
> I'm trying to use regexp_replace to get rid of all occurrences of
> certain sub strings from my string.
> What I'm doing is:
>
> SELECT regexp_replace('F0301 305-149-101-0 F0302 {x1} 12W47 0635H
> {tt}{POL23423423}', E'\{.+\}', '', 'g')
>
> so get rid of whatever is between { } along with these,
>
> but it results in:
> 'F0301 305-149-101-0 F0302 '
>
> how do I get it to be:
> 'F0301 305-149-101-0 F0302 12W47 0635H'
>
> ??
>
> as I understood the docs, the g flag "specifies replacement of each
> matching substring rather than only the first one"

The first \{.+\} match starts at the first { and ends at the last },
eating the {s and }s in the middle.  So there's only one match and that's
what's removed.

> what am I missing ?

You need a non-greedy quantifier.  Try

 SELECT regexp_replace('F0301 305-149-101-0 F0302 {x1} 12W47 0635H {tt}{POL23423423}', E'\{.+?\}', '', 'g')

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