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Re: difference between READ and SCAN
Posted by: Linhai Song
Date: June 21, 2012 12:19PM

I am reading mysql-cluster source code.

In storage/ndb/src/kernel/blocks/dbacc/DbaccMain.cpp file, I find ZSCAN_OP and ZREAD. I guess these are used to describe execution plan. But I do not understand when mysql will use ZSCAN_OP and when mysql will use ZREAD.


I also find that in void Dbacc::execACC_COMMITREQ(Signal* signal) function, there is a check to see whether operation type is ZREAD. Is it possible that operation type is ZREAD in COMITREQ function?

Thanks a lot!

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difference between READ and SCAN
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Linhai Song
June 20, 2012 04:05PM
Re: difference between READ and SCAN
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Rick James
June 20, 2012 08:23PM
Re: difference between READ and SCAN
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Linhai Song
June 21, 2012 12:19PM


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