Re: Add PK constraint to a Unique Index via updating system catalogs? - Mailing list pgsql-general

CS DBA wrote on 06.01.2014 23:30:
> We have a few very large tables with unique indexes on a column but
> the column is not defined as the Primary Key.  Can we add a PK
> constraint via updates to the system catalogs so we can avoid the
> lengthy checks that would take place if we ran "alter table add
> constraint primary key...."
>

You can add a PK constraint with the "USING INDEX" clause:

alter table foo
    add primary key
    using index unique_index_name;