On Thu, Jul 10, 2008 at 1:22 PM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote: > "Scott Marlowe" <scott.marlowe@xxxxxxxxx> writes: >> ...Which is not surprising. It's greedy. So, I turn off the greediness >> of the first + with a ? and then I get this > >> select substring (notes from E'LONG DB QUERY.+?time: [0-9]+.[0-9]+') >> from table where id=1; > >> LONG DB QUERY (db1, 4.9376289844513): UPDATE force_session SET >> last_used_timestamp = 'now'::timestamp WHERE orgid = 15723 AND >> session_id = 'f5ca5ec95965e8ac99ec9bc31eca84c6New session created >> time: 5.0 > >> Now, I'm pretty sure that with the [0-9]+.[0-9]+ I should be getting >> 5.03999090194 at the end. > > You're getting bit by the fact that the initial non-greedy quantifier > makes the entire regex non-greedy --- see rules in section 9.7.3.5: > http://developer.postgresql.org/pgdocs/postgres/functions-matching.html#POSIX-MATCHING-RULES > > If you know that there will always be something after the first time > value, you could do something like > > E'(LONG DB QUERY.+?time: [0-9]+\\.[0-9]+)[^0-9]' > > to force the issue about how much the second and third quantifiers > match. Thanks Tom, that's the exact answer I needed. Now, it's back to the bit mines...
