Re: Try adding type cast with tablespace

Hello,Yuki.

My understanding is that your patch is aimed to enrich an alias type for oid.
There are already some alias types for oid so I think it is good to
add regtablespace for convenience.

https://www.postgresql.org/docs/16/datatype-oid.html#DATATYPE-OID-TABLE

Actually,I also felt it is a bit of a hassle to join tables to find
tablespace name from pg_database,
it is convenient if I can use regtablespace alias.

Therefore I think it is good to add regtablespace alias,but I’m also
newbie pgsql-hackers.
We need some senior hackers’s opinions.

Kind Regards,
Kenichiro Tanaka
>
> 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