Blessings upon ye monks!

First, this question is total Monk abuse. It's an SQL question, not a perl question (though I will be using the advice generated by this question in a perl script.) However, the Monks are the best people on the net, the smartest, the best able to parse my stupidly-worded questions, sexiest, best dressed etc... If I wanted advice buying a car, I would probably ask on PerlMonks...

If you know a good, more appropriate venue for this kind of question, please feel free to include it with your downvote.

Achem.. the question...

I want to get all the rows out of a table where one particular field has the same value in at least two rows. Er... I want all the rows with matching values in a particular field, and I don't know what the values are, I just want the ones where that value matches.

Here's the background:

I'm looking for duplicate files on my computer.

I have two tables in sqlite like so: 

create table files ( id integer primary key, path text unique, md5 int
+eger);
create table md5s ( id integer primary key, md5 text unique);

[download]

A process (writen in perl!) is presently running that is filling up these tables such that each file's md5 integer is the id integer in the md5s table. I want to get the names of files that have the same md5sum, and I'm almost positive I can do that with a select statement but I have no idea how to start.

Did I mention I suck at SQL? I suck at SQL.

Again, any links to good resource for a loser like me would be greatly appreciated and might even lead to fewer stupid questions like this wasting your time.

Let the downvotes begin!

--Pileofrogs

In reply to Dumb SQL Question by pileofrogs

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