"Tom Lane" <[EMAIL PROTECTED]> writes: > 2. Page format conversion is WAL-logged as a complete page replacement
It seems we get that for free. By definition any modification to a page after conversion will be the first record for that page since a checkpoint. It just means we have to force full_page_writes to be true, at least for a buffer that's been converted if not whenever we're processing a mixed format database. > On the whole I think we could define format conversions for user-defined > types as "not our problem". Hm, perhaps we could do it by doing as much of the work up-front as possible. Requiring datatypes to define a function in pg_proc to do the conversion and require that it be a function which can stand on its own without catalog lookups or other facilities. Then when we start up on a mixed format database we load all those functions into a hash by typeoid and provide that hash to bufmgr. By definition any datatypes we expect to find in the database must already be in the catalog before we start. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
