2015-02-02 11:15 GMT+01:00 Pavel Stehule <pavel.steh...@gmail.com>: > Hello > > Six years ago we did discuss about global temporary tables - persistent > schema, ephemeral data. > > http://postgresql.nabble.com/idea-global-temp-tables-td2007217.html > > 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. >
I forgot other possible benefit: * using temp tables on slaves - (needs 3c implementation) > > 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 >
