I am thinking so some reasons why implement this feature are valid:
* we can get some performance benefit against current temp tables - less the catalogue bloating,
* we can simplify a static validation of plpgsql functions when temp tables are used,
more global temp tables are little bit comfortable for developers,
* we can simplify migration from some other databases, where global temp tables are default.
Some was changed from 2009:
* We have updatable CTE
* We have unlogged tables
Opened questions:
1. Name and conformance with standard of this feature - because we doesn't support modules, a mapping ANSI -> PG should not be trivial
2. Implementation
I see three possible ways how to implement it:
2.a - using on demand created temp tables - most simple solution, but doesn't help with catalogue bloating
2.b - using unlogged tables for holding statistics, relfilenode, and all necessary data
3.c - store ephemeral metadata only in memory without MVCC
Is there still interest about this feature?
Comments, notes?
Pavel
