Thread: Add PK constraint to a Unique Index via updating system catalogs?

Hi All;

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...."


Thanks in advance

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;

Any way to add a PK "under the covers" for PostgreSQL version 8.3?





On 01/06/2014 03:53 PM, Thomas Kellerer wrote:
> 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;
>
>
>
>
>