Similarity Search with Wildcards

[Ghislain Hachey <ghachey@xxxxxxxxx>]

Hi list,

I have a varchar column with content such as "Client Name - Brief Description of Problem" (it's a help desk ticket system). I want to generate reports by clients and the only thing I can base my query on is this column. The client names often contain typos or are entered slightly differently. I installed the pg_trgm extension and it almost does what I want. The problem is that it searches the similarity of the whole field and not just the client name resulting in not so similar searches (I include my query below).

SELECT
  tickets.id as ticket_id, 
  tickets.subject as ticket_subject,
  similarity(tickets.subject, 'Client Name') AS sml,
FROM
 tickets
WHERE
  tickets.subject % 'Client Name';
 
I thought about using wildcards as discussed here <http://www.postgresql.org/message-id/flat/4D3CC2DC.6060002@xxxxxxxxxxx#4D3CC2DC.6060002@xxxxxxxxxxx> but this does not seem to have any effect (I include the query I tried below).

SELECT
  tickets.id as ticket_id, 
  tickets.subject as ticket_subject,
  similarity(tickets.subject, '%Client Name%') AS sml,
FROM
 tickets
WHERE
  tickets.subject % '%Client Name%';

Both queries result in the same similarity. I would hope that the similarity algorithm would only work on the "Client Name" part of the string and ignore what is before and after; in other words, the latter query above would return a similarity factor of 1 on the content "Client Name - Brief Description of Problem".

Any pointer in a right direction would be appreciated.

--
GH