Re: Block-level CRC checks

decibel wrote:
> On Dec 3, 2009, at 1:53 PM, Jonah H. Harris wrote:
> > On Tue, Dec 1, 2009 at 1:27 PM, Joshua D. Drake  
> > <jd@commandprompt.com> wrote:
> > On Tue, 2009-12-01 at 13:20 -0500, Robert Haas wrote:
> > > Does $COMPETITOR offer this feature?
> > >
> >
> > My understanding is that MSSQL does. I am not sure about Oracle. Those
> > are the only two I run into (I don't run into MySQL at all). I know
> > others likely compete in the DB2 space.
> >
> > To my knowledge, MySQL, InnoDB, BerkeleyDB, solidDB, Oracle, SQL  
> > Server, Sybase, DB2, eXtremeDB, RDB, and Teradata all checksum pages.
> 
> 
> So... now that the upgrade discussion seems to have died down... was  
> any consensus reached on how to do said checksumming?

I think the hint bit has to be added to the item pointer, by using the
offset bits that are already zero, according to Greg Stark.  That
solution leads to easy programming, no expanding hint bit array, and it
is backward compatible so doesn't cause problems for pg_migrator.

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