On Fri, 5 Mar 2004, Jeff wrote: > Is there any performance advantage to using a fixed width row (with PG)?
As far as I know there is only a small win when you want to extract some field from a tuple and with variable width fields you have to walk to the correct field. But this is a small performance problem unless you have very many variable size columns in the table. > different databases and we have also some custom software here that > uses fixed width rows to be able to hit row N in O(1) This can not happen in pg since there is no row N. Every transaction can have a different view of the table, some rows are visible and some others are not. To find row N you have to walk from the start and inspect every tuple to see if it's visible to this transaction or not. -- /Dennis Björklund ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]
