Re: CREATE INDEX and HOT - revised design

Bruce Momjian wrote:
> > Also, I am wondering whether the information that which index is used to
> > fetch a tuple is always available. I haven't checked, but do we have that
> > information in lossy bitmap heapscan ?
> 
> Oh, that is an interesting problem because an index might have one index
> entry representing an entire HOT chain, while another index might
> represent each chain member by individual index entries.  When we do the
> bitmaps, don't we access them by heap tid, meaning we would find all
> entries anyway?

I thinking some more, it would be a problem because while we are merging
the tids, we are using index entries and haven't looked at the heap yet.
I am guessing we would have to exclude the new index from bitmap joins
with other indexes until the VACUUM happens.

--  Bruce Momjian  <bruce@momjian.us>          http://momjian.us EnterpriseDB
http://www.enterprisedb.com
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