On Thu, Aug 16, 2007 at 04:06:35PM -0400, Alvaro Herrera wrote: > Jeff Davis wrote: > > On Wed, 2007-08-15 at 11:54 -0400, Bruce Momjian wrote: > > > I have added another idea for index-only scans to the TODO list: > > > > > > > A third idea would be for a heap scan to check if all rows are visible > > > > and if so set a per-table flag which can be checked by index scans. > > > > Any change to the table would have to clear the flag. To detect > > > > changes during the heap scan a counter could be set at the start and > > > > checked at the end --- if it is the same, the table has not been > > > > modified --- any table change would increment the counter. > > > > This sounds useful for read-only or read-mostly tables. > > I think it's too coarse-grained to be really useful. If it was one bit > per page it could work, but one bit per relation is going to be reset > too frequently.
Not for the most common use cases for table partitioning. -- Decibel!, aka Jim Nasby [EMAIL PROTECTED] EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)
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