Re: Mimic ALIAS in Postgresql?

On 1/16/24 11:20 AM, Ron Johnson wrote:
> Some RDBMSs have CREATE ALIAS, which allows you to refer to a table by a 
> different name (while also referring to it by the original name).
> 
> We have an application running on DB2/UDB which (for reasons wholly 
> unknown to me, and probably also to the current developer) extensively 
> uses this with two schemas: MTUSER and MTQRY.  For example, sometimes 
> refer to MTUSER.sometable and other times refer to it as MYQRY.sometable.
> 
> My goal is to present a way to migrate from UDB to PG with as few 
> application changes as possible.  Thus, the need to mimic aliases.
> 
> Maybe updatable views?
> CREATE VIEW mtqry.sometable AS SELECT * FROM mtuser.sometable;

Based on the schema names one possibility is that the aliases are there 
as a pseudo-api between people/tools writing queries and the base 
tables. IE: if you needed to make a (maybe backwards-incompatible) 
change to "sometable" you now at least have the option of creating a 
MTQRY.sometable *view* that hides whatever change you're making to 
MTUSER.sometable.

In any case, yes, an updatable view would provide equivalent behavior in 
Postgres.
-- 
Jim Nasby, Data Architect, Austin TX