Try adding type cast with tablespace

Hi all,

Good day!

I am a newbee to PostgreSQL and recently came across an idea about type-casting tablespace OID.

The motibation is that when I have to upgrade a PostgreSQL database, we need to join other tables to 

track tablespace name. I have just created a simple patch to resolve this.

Hope you can take a look with this.

My Execution Sample:

# After Patch:

------------------------------------------------------------------------

postgres=# SELECT oid,oid::regtablespace,spcname from pg_tablespace ;

 oid  |    oid     |  spcname

------+------------+------------

 1663 | pg_default | pg_default

 1664 | pg_global  | pg_global

(2 rows)

------------------------------------------------------------------------

# Before Patch

------------------------------------------------------------------------

postgres-# SELECT oid,oid::regtablespace,spcname from pg_tablespace ;

ERROR:  syntax error at or near "oid"

LINE 1: oid  |    oid     |  spcname

        ^

------------------------------------------------------------------------

I added the "::regtablespace" part to source.

Note: While developing, I also had to add several rows to pgcatalog tables.

      Please point out if any OID newly assigned is not appropriate.

Kind Regards,

Yuki Tei