Re: Reverse pattern match.

Moonstruck,

> I want to create a table of regular expression patterns (for assessing
> phone numbers), something like:
> CREATE TABLE CallType ( pattern varchar primary key,
> type varchar,
> rate int4);
> INSERT INTO CallType VALUES ('0[3-9]________','Interstate Call',50);
> INSERT INTO CallType VALUES ('9_______','Local Call',25);
> INSERT INTO CallType VALUES ('0011__________%','International Call',100);

PostgreSQL supports real Regular Expressions, via the ~ operator. See "~"
under "functions and operators", and then consult your favorite book or
online ressouce on how to compose regexps.

An example of "is not in 415 area code" would be
phone_no ~ '^415\d{7}'
which should be "415" at the beginning followed by at least 7 other digits.

(Folks, please correct my regex code if it's bad!)

The disadvantage to this approach is that it cannot be indexed.

--
-Josh Berkus
Aglio Database Solutions
San Francisco