I have a simple table model for a many-many r'ship between keys and sigs:
KEYS table has columns: key, keyID
SIGS table has columns: sig, sigID
KEYS_SIGS has columns: keyID, sigID
For a given key X, how can I retrieve all the sigs that are related to it?
Conceptually, I need three SELECTS:
#1. SELECT keyID FROM keys
WHERE key = X
#2. SELECT sigID FROM keys_sigs
WHERE keyID = (result of #1)
SELECT sig FROM sigs
WHERE sigID = (result of #2)
I tried nesting these queries, but PG complained that my subselect had
produced multiple values -- which of course it can.
