searching tables for a pattern that is in some other text

suppose I have a text file and I am looking for a pattern in that file
of the regex form: /^\s*#{label}\s*:?\s*(.*)/i
Where 'label' is a variable, but I want to do something like this:

labels.each do |lab|
  if line =~ /^\s*#{lab}\s*:?\s*(.*)/i
    matched = lab
  end
end

If labels are stored in the database, is there a good faster way to do
this ?

Postgresql understands the SIMILAR TO command, which uses a SQL
version of regular expressions: http://www.postgresql.org/docs/8.3/static/functions-matching.html

Not sure if that is general SQL or postgres specific though, and I'd
also image the SQL regular expressions are a little less powerful, but
you may be able to accomplish what you want.

\Peter