Re: support for CREATE MODULE

On 2022-Feb-04, Swaha Miller wrote:

> The POC patch Jim Mlodgenski had on that thread was similar to your
> proposed way - modules were rows in pg_namespace, with the addition of
> a new column in pg_namespace for the nspkind (module or schema.)

I don't agree that what he proposed was similar to my proposal. The
main problem I saw in his proposal is that he was saying that modules
would be *within* schemas, which is where I think the whole thing
derailed completely.

He said:

> [ This patch ] [...] allows for 3-part (or 4 with the database name)
> naming of objects within the module.

He then showed the following example:

> CREATE SCHEMA foo;
> CREATE MODULE foo.bar
> CREATE FUNCTION hello() [...]
> SELECT foo.bar.hello();

Notice the three-part name there. That's a disaster, because the name
resolution rules become very complicated or ambiguous. What I describe
avoids that disaster, by forcing there to be two-part names only: a
module lives on its own, not in a schema, so a function name always has
at most two parts (never three), and the first part can always be
resolved down to a pg_namespace row of some kind.

--
Álvaro Herrera 39°49'30"S 73°17'W — https://www.EnterpriseDB.com/
"La conclusión que podemos sacar de esos estudios es que
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