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Index only scans and visibilitymap.c - Mailing list pgsql-hackers

From	Jeff Janes
Subject	Index only scans and visibilitymap.c
Date	October 23, 2011 19:41:12
Msg-id	CAMkU=1wo4Od9Xc5-C4Yojx-5Z+ps-dgD28pja=DcYdwqxm8Wsw@mail.gmail.com Whole thread Raw
List	pgsql-hackers

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With index only scans, the comments in
src/backend/access/heap/visibilitymap.c are probably out of date,
starting with:

"Currently, the visibility map is only used as a hint"


Also, is there a discussion of how and why index-only scans is safe?
i.e. what lock, if any, has to be held while nodeIndexonlyscan.c
calls  visibilitymap_test?  Do index-only scans need a README file?

Thanks,

Jeff

pgsql-hackers by date:

From: Simon Riggs
Date: 23 October 2011, 19:39:15
Subject: Re: Hot Backup with rsync fails at pg_clog if under load

From: Jeff Janes
Date: 23 October 2011, 20:01:09
Subject: Re: So, is COUNT(*) fast now?

Index only scans and visibilitymap.c - Mailing list pgsql-hackers

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