Added Support for Arbitrary Table Engines in Temporary Tables

Why it matters

This feature enables users to create temporary tables with any supported engine type, providing greater flexibility and the ability to optimize temporary table behavior according to specific use cases. It solves the limitation where temporary tables were restricted to a fixed set of engines, thus expanding the use cases for temporary tables.

How to use it

When creating temporary tables, specify the desired table engine in the CREATE TEMPORARY TABLE statement as you would with regular tables. Note that Replicated and KeeperMap engines are still not supported for temporary tables. Example:

CREATE TEMPORARY TABLE temp_table ENGINE = <engine_name> AS <query>;