Обсуждение: Dropping sub-tables
Say I have a table for equipment having columns for ordinary equipment. It also has sub-tables for things like sensors with extra columns for specialty info. I'd like to revert to having only the main table without any sub-tables, but keep the rows from the sub-tables which are common to the parent table. If I drop the sub-tables, do I loose all if their rows, or only the columns not shared with the parent table? TIA,
On Wed, 2006-02-01 at 17:59 -0500, Gan Uesli Starling wrote: > Say I have a table for equipment having columns for ordinary > equipment. It also has sub-tables for things like sensors with > extra columns for specialty info. > > I'd like to revert to having only the main table without any > sub-tables, but keep the rows from the sub-tables which are > common to the parent table. > > If I drop the sub-tables, do I loose all if their rows, or > only the columns not shared with the parent table? I assume you are talking about inheritance, so the answer is yes, you will lose all their rows. -- Oliver Elphick olly@lfix.co.uk Isle of Wight http://www.lfix.co.uk/oliver GPG: 1024D/A54310EA 92C8 39E7 280E 3631 3F0E 1EC0 5664 7A2F A543 10EA ======================================== Do you want to know God? http://www.lfix.co.uk/knowing_god.html