Re: Schema variables - new implementation for Postgres 15

pá 31. 5. 2024 v 13:37 odesílatel Wolfgang Walther <walther@technowledgy.de> napsal:

Pavel Stehule:
>     But in this case you could make variables and tables share the same
>     namespace, i.e. forbid creating a variable with the same name as an
>     already existing table.
>
>
> It helps, but not on 100% - there is a search path

I think we can ignore the search_path for this discussion. That's not a
problem of variables vs tables, but just a search path related problem.
It is exactly the same thing right now, when you create a new table x(x)
in a schema which happens to be earlier in your search path.

 

I don't think it is a valid argument - search_path is there, and we cannot ignore it, because it allows just one case.

And the need to use a variable in FROM clause introduces implicit unpacking or inconsistency with current work with composite's types, so I am more sure this way is not good.

 

The objection to the proposed approach for variables was that it would
introduce *new* ambiguities, which Alvaro's suggestion avoids.

Best,

Wolfgang