\d medium says I have index:
"medium2013_pkey" PRIMARY KEY, btree (id)

\d track says I have index:
"track2013_pkey" PRIMARY KEY, btree (id)
and constraints:
"track2013_edits_pending_check" CHECK (edits_pending >= 0)
"track2013_length_check" CHECK (length IS NULL OR length > 0)

and Ian tells me they should not be called that.