Dmitriy Igrishin <dmitigr(at)gmail(dot)com> writes:
> How can I select names of indexes of table (or even whole schema) that are
> not dependent on constraints?
Right at the moment, the only reliable way to tell whether an index is
associated with a constraint is to look for a pg_depend entry linking
the two. Be careful to consider only "internal" dependencies, else you
may be fooled by foreign-key constraints that depend on indexes.
If you look into the pg_dump source code you will find an example.
9.0 will make this a tad simpler by keeping a "conindid" column in
pg_constraint.
regards, tom lane