fuzzy merging two tables postgresql - postgresql

Question

I need to join two tables based on names. And the problem is that names may be a slight mispelling in one of the database. I have remedy this problem in the past using Stata and Python's fuzzy merging, where names are matched based on how closely similar they are, but I am wondering if this is possible to do in Postgresql.
For example, may data may be something similar to this:
Table A:
first_name_a | last_name_a | id_a
----------------------------------
William | Hartnell | 1
Matt | Smithe | 2
Paul | McGann | 3
David | Tennant | 4
Colin | Baker | 5
Table B:
first_name_b | last_name_b | id_b
----------------------------------
Matt | Smith | a
Peter | Davison | b
Dave | Tennant | c
Colin | Baker | d
Will | Hartnel | e
And in the end, I hope my results would look something like:
first_name_a | last_name_a | id_a | first_name_b | last_name_b | id_b
----------------------------------------------------------------------
William | Hartnell | 1 | Will | Hartnel | e
Matt | Smithe | 2 | Matt | Smith | a
Paul | McGann | 3 | | |
David | Tennant | 4 | Dave | Tennant | c
Colin | Baker | 5 | Colin | Baker | d
| | | Peter | Davison | b
My Sonic Screwdriver gives me some pseudo-code like this:
SELECT a.*, b.* FROM A a
JOIN B b
WHERE LEVENSHTEIN(first_name_a, first_name_b) IS LESS THAN 1
AND LEVENSHTEIN(last_name_a, last_name_b) IS LESS THAN 1

Answer 1

The DML you mention:
SELECT a.*, b.* FROM A a
JOIN B b
WHERE LEVENSHTEIN(first_name_a, first_name_b) IS LESS THAN 1
AND LEVENSHTEIN(last_name_a, last_name_b) IS LESS THAN 1
Looks correct, just bump up the 'fuzziness' (given 'IS LESS THAN 1' substitute 1 for the 'fuzzyness' level that you you require)
See http://www.postgresql.org/docs/9.1/static/fuzzystrmatch.html for reference info on LEVENSHTEIN.

Answer 2

Done up as an SQLFiddle. Play with the thresholds/look at some of the other mapping functions mentioned in matching fuzzy strings.