On Wed, 2007-03-21 at 10:47 -0400, Bruce Momjian wrote: > A different idea is to flag the _index_ as using HOT for the table or > not, using a boolean in pg_index. The idea is that when a new index is > created, it has its HOT boolean set to false and indexes all tuples and > ignores HOT chains. Then doing lookups using that index, the new index > does not follow HOT chains. We also add a boolean to pg_class to > indicate no new HOT chains should be created and set that to false once > the new index is created. Then, at some later time when all HOT chains > are dead, we can enable HOT chain following for the new index and allow > new HOT chains to be created.
"enable HOT chain following" would require us to hold an AccessExclusiveLock on the index. We know that solution exists, the question is: at what point would we ever request that lock? Or would we just wait until that lock is next taken before enabling it, giving the user no control over when its taken? A separate DDL command would be effectively the same as what Pavan has recently suggested. -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
