Disallow out of range numerics type on table creation

[dentiny]

Followup PR for issue #47
This PR disallows table creation when out-of-range (for duckdb) numerics types created.

The implementation here copies the type checking logic into columnstore_handle.cpp.
Pro: Having the check logic outside of pg_duckdb reduces the overhead for upgrade
Con: Need to maintain two util functions to get scale and width, every time we upgrade pg_duckdb.

Alternative considered:
Method-1: add extra type conversion code in pg_duckdb.
Example code

if (scale > 38) return duckdb::USER(...)

Pro: least possible code change
Con: every time we upgrade pg_duckdb, the extra checking logic has to be cherry-picked also

Method-2: propagate the logic to table creation logic into pg_duckdb
It doesn't work because pg_duckdb doesn't support general-purpose table creation as of now;
Moving the logic into pg type -> duck type conversion is also not proper.

How I tested:

postgres (pid: 32200) =# CREATE TABLE mooncake_numeric_tbl_2 (val numeric(40, 5)) USING columnst
ore;
ERROR:  Unsupported type when creating column: type precision 40 with scale 5 is not supported by duckdb
postgres (pid: 32200) =# CREATE TABLE mooncake_numeric_tbl_2 (val numeric) USING columnstore;
ERROR:  Unsupported type when creating column: type precision 65535 with scale -5 is not supported by duckdb
postgres (pid: 32200) =# CREATE TABLE mooncake_numeric_tbl_2 (val numeric(38, 3)) USING columnst
ore;
CREATE TABLE

[dpxcc]

It seems good to also have the same lockdown for pg_duckdb's temp DuckDB table?
So it might be better to make this change to pg_duckdb instead?

[dentiny]

If I don't read it wrong, this is how pg_duckdb handles temp table creation:
https://github.com/duckdb/pg_duckdb/blob/bb82c937936b97824bb766893745e1456eb1aa08/src/pgduckdb_ddl.cpp#L199-L364

Considering the fact that pg_duckdb doesn't support complete table creation functionality, I think it would be nice if:

• pg_duckdb locks down temp table creation on duckdb-incompatible types
• pg_mooncake locks down table creation on duckdb-incompatible types

It seems good to also have the same lockdown for pg_duckdb's temp DuckDB table?

To your question, yes.

So it might be better to make this change to pg_duckdb instead?

But I'm not sure how we could place the whole lock down logic into pg_duckdb?
Since it only handles part of the table creation logic as of now.

I mentioned it briefly in the PR description:

Method-2: propagate the logic to table creation logic into pg_duckdb
It doesn't work because pg_duckdb doesn't support general-purpose table creation as of now;
Moving the logic into pg type -> duck type conversion is also not proper.

Let me know if I mis-understand pg_duckdb's capability.

[dpxcc]

Yes, the creation of columnstore tables and DuckDB temporary tables follow different code paths
My suggestion was only to move the helper functions numeric_typmod_precision, numeric_typmod_scale, and ValidateColumnNumericType in this file to pg_duckdb
I noticed you just opened duckdb/pg_duckdb#471, which already addresses this
We just need to wait for that diff to land and re-pull from pg_duckdb

[dpxcc]

We just need to wait for duckdb/pg_duckdb#471 to land and re-pull from pg_duckdb

[dpxcc]

Yes, the creation of columnstore tables and DuckDB temporary tables follow different code paths
My suggestion was only to move the helper functions numeric_typmod_precision, numeric_typmod_scale, and ValidateColumnNumericType in this file to pg_duckdb
I noticed you just opened duckdb/pg_duckdb#471, which already addresses this
We just need to wait for that diff to land and re-pull from pg_duckdb