Andy Colson <andy(at)squeakycode(dot)net> writes:
> This is not doing as I'd expected:
> select regexp_replace('71.09.6.01.3', '(\d)[.-](\d)', '\1\2', 'g');
> regexp_replace
> ----------------
> 71096.013
> (1 row)
I think regexp_replace considers only non-overlapping substrings,
eg, once it's replaced 1.0 with 10, it then picks up searching at
the 9 rather than starting over. The dot after 6 doesn't get
removed because the 6 can't belong to two replaceable substrings, and
it already got consumed in the process of removing the dot before 6.
I might be wrong, but I think two passes of regexp_replace would
do what you want in this example.
regards, tom lane