Thread: Querying constraints?

Hi,

Is is possible to query from my application whether there is a primary 
key or unique constraint on a given table and field name(s)?

Thanks
LL

> Is is possible to query from my application whether there is a primary 
> key or unique constraint on a given table and field name(s)?

Curiously enough, I just answered a similar question on the pgsql-admin
list. Try this:

SELECT c.relname as table, r.conname as contraint_name, r.contype as
contraint_type, pg_catalog.pg_get_constraintdef(r.oid, true) as
constraint_definition FROM pg_catalog.pg_constraint r,
pg_catalog.pg_class c WHERE c.oid = r.conrelid;

Bye,
Chris

-- 

Chris Mair
http://www.1006.org

> Curiously enough, I just answered a similar question on the pgsql-admin
> list. Try this:
> 
> SELECT c.relname as table, r.conname as contraint_name, r.contype as
> contraint_type, pg_catalog.pg_get_constraintdef(r.oid, true) as
> constraint_definition FROM pg_catalog.pg_constraint r,
> pg_catalog.pg_class c WHERE c.oid = r.conrelid;

I forgot to mention, it's tested on 8.1...

Bye, Chris.

-- 

Chris Mair
http://www.1006.org