Re: reindex creates predicate lock on index root

Excerpts from Kevin Grittner's message of mar jun 07 20:45:43 -0400 2011:
> During testing of the SSI DDL changes I noticed that a REINDEX INDEX
> created a predicate lock on page 0 of the index.

Err, in a btree, page 0 is the metapage, not the root.  The root page
moves around, but it's never page 0 (it starts at page 1).  I think GIN
indexes also have metapages, not sure about the others.

Not sure if this changes your reasoning at all, just thought it was
worth mentioning.

> This is pretty
> harmless, but mildly annoying.  There are a few other places where
> it would be good to suppress predicate locks; these are listed on
> the R&D section of the Wiki.  I hope to clean some of these up in
> 9.2. Unless a very clean and safe fix for the subject issue pops out
> on further review, I'll add this to that list.

-- 
Álvaro Herrera <alvherre@commandprompt.com>
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