That's what I'm testing right now... thanks a lot for the heads up... b On Nov 14, 2007 1:41 AM, Trevor Talbot <[EMAIL PROTECTED]> wrote: > On 11/13/07, Benilton Carvalho <[EMAIL PROTECTED]> wrote: > > > Then each column is added on the fly, using: > > > > ALTER TABLE table ADD COLUMN colunm REAL; > > > > The columns in then filled used UPDATE as described previously. > > I haven't investigated the storage layout of this, but from what the > docs imply, I suspect making use of ADD COLUMN will result in SELECTs > being as slow as UPDATEs, possibly worse. When I said I expect the > final queries to be faster, I was envisioning all of the columns > created initially, just filled with zeros. I suspect filling them > with NULL initially would make update performance worse also. > > I'll let others confirm/deny this, and comment on the performance of > ADD COLUMN in general. > > > ----------------------------------------------------------------------------- > To unsubscribe, send email to [EMAIL PROTECTED] > ----------------------------------------------------------------------------- > >
----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
