Martijn van Oosterhout <[email protected]> writes:
> On the otherhand, I think requiring an "overall longest match" makes
> your implementation non-polynomial complexity.
Only if you don't know how to implement it -- a DFA-based implementation
doesn't have much trouble with this.
> [ equivalence of knapsack problem to regexes with bounded repetition ]
Interesting, but note that neither the POSIX spec nor our implementation
permit arbitrarily large repetition counts, so the theoretical
NP-completeness is only theoretical.
> The question is, what are users expecting of the PostgreSQL regex
> implementation?
I think a minimum expectation is that we adhere to the POSIX
specification.
regards, tom lane
--
Sent via pgsql-hackers mailing list ([email protected])
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
