Re: [HACKERS] path toward faster partition pruning

On 2018/04/11 21:35, Alvaro Herrera wrote:
> Here's an idea.  Why don't we move the function/opclass creation lines
> to insert.sql, without the DROPs, and use the same functions/opclasses
> in the three tests insert.sql, alter_table.sql, hash_part.sql and
> partition_prune.sql, i.e. not recreate what are essentially the same
> objects three times?  This also leaves them around for the pg_upgrade
> test, which is not a bad thing.
> 
> (This would require a few updates to insert.sql because the definitions
> there are different, but it shouldn't be a problem coverage-wise.)

OK, I've tried doing that.  Needed adjustments to hash_part.sql as well.
The hash function for int4 was defined differently in insert.sql,
alter_table.sql, and hash_part.sql.  I went with the definition in
insert.sql, which although slightly different from the one
alter_table.sql, didn't affect the latter's output in any way.  Since the
definition in hash_part.sql was totally different, a couple of tests
needed adjusting after starting to use hash opclasses defined in insert.sql.

Attached updated patch.

PS: git grep "partition by hash\|PARTITION BY HASH" on src/test indicates
that there are hash partitioning related tests in create_table,
foreign_key, and partition_join files as well.  Do we want to use the
custom opclass in those files as well?

Thanks,
Amit