Re: Finding the primary key of tables

[George Silva <georger.silva@xxxxxxxxx>]

I'm going for Merlin's solution. Its the easiest one :P

But I'm also having a problem:

SELECT column_name FROM information_schema.key_column_usage k
    LEFT OUTER JOIN information_schema.table_constraints ON (k.table_name = table_constraints.table_name)

WHERE
        table_constraints.constraint_type = 'PRIMARY KEY'
        AND k.table_name = 'acidentes'
        AND k.table_schema = 'public'

this still returns me multiple columns. Did I forgot something?

2010/8/3 Devrim GÜNDÜZ <devrim@xxxxxxxxxx>

On Tue, 2010-08-03 at 16:13 -0300, George Silva wrote:
> I'm building a function which needs to know what is the primary key of
> a
> certain table (all in pgplsql).
>
> I was using select * from information_schema.key_column_usage where
> table_schema='foo' and table_name = 'aaa'; but that will give me
> multiple
> results in case of additional keys in the table.
>
> Any suggestions?

See pg_index.indisprimary column. If it is true, then the it is the PK
of given table.

Regards,
--
Devrim GÜNDÜZ
PostgreSQL Danışmanı/Consultant, Red Hat Certified Engineer
PostgreSQL RPM Repository: http://yum.pgrpms.org
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-- 
George R. C. Silva

Desenvolvimento em GIS
http://blog.geoprocessamento.net