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  1. #1
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    Unanswered: afraid to admit...

    I have db2 certificates so I'm suppose to know it all..... yeah right!

    Currently I am analyzing "db2pd tcbstats" output and here (db2pd to monitor table access) I read about "RID Scans".... Ehhh what ís a RID scan? Must have missed it or forgot all about it.
    I understand it spoils the significance of the "scans" column in my db2pd report, but what else does it do?

  2. #2
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  3. #3
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    Thanks. 'Super Moderator' really means something .
    So a RID scan a.k.a. RIDSCN is good and only indicates that the prefetching is taking place.
    The "scans" column on my db2pd report is bad because it does not contain any valueable information because bad tablescans and good ridscans are mixed.

  4. #4
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    Quote Originally Posted by dr_te_z View Post
    Thanks. 'Super Moderator' really means something .
    yeh, does mean something! I can delete threads and ban users that I don't like
    Quote Originally Posted by dr_te_z View Post
    So a RID scan a.k.a. RIDSCN is good and only indicates that the prefetching is taking place.
    The "scans" column on my db2pd report is bad because it does not contain any valueable information because bad tablescans and good ridscans are mixed.
    RIDSCAN is better than a tablescan, but not necessarily a good thing.

    Full index scans often result in RIDSCANs. Thoguh full index scans are better than full tablescans, they are not good.

    There may be scope for reindexing or rewriting queries.
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