#DateWhereItemComment
37014 Mar 2014 @ 11:46 PDTData Warehouse DisruptionBig Data and Social Media: a Threatened Future?John,   I love your blog and try to read your postings as soon as they pop up.  This one was particularly thought-provoking.   Keep 'em coming!   - Carrie
36913 Mar 2014 @ 01:09 PDTcarrie's blogHow Resources are Shared in the SLES 11 Priority Scheduler#1:  There is no one answer to where you should place your utility workload.  It depends on its priority and the priority of other work running in the system at the same time.  ...
36813 Mar 2014 @ 12:53 PDTcarrie's blogStatistics collection recommendations – Teradata 14.0#1.  There is no default ordering for multicolumn stats in 14.0 and above.  The order you define the columns in the COLLECT STATS statement determines their ordering.   #2.  I...
36707 Mar 2014 @ 04:24 PSTcarrie's blogAutomatic Throttles in Teradata 14.0 and 14.10Suhail,   The new blog posting has been completed.  Hopefully it will answer your questions.   Thanks, -Carrie
36605 Mar 2014 @ 08:21 PSTcarrie's blogAutomatic Throttles in Teradata 14.0 and 14.10Suhail,   Because your comment/question concerns a  different topic from the blog posting it was attached to, it would make more sense for me to address it in a posting that is directly...
36527 Feb 2014 @ 12:38 PSTcarrie's blogEliminating Unplanned Delays Within Load Utility JobsYes,  make sure whichever workload the auxiliary SQL goes to does NOT have a workload throttle.   And in order for the SQL to classify there the workload must NOT have...
36426 Feb 2014 @ 09:36 PSTcarrie's blogEliminating Unplanned Delays Within Load Utility JobsHi Cam,   Response to #1:  A utility throttle will not impact or have any control over an auxiliary session SQL.  The auxiliary session, if there is one, is not included in the uti...
36310 Feb 2014 @ 12:33 PSTcarrie's blogStatistics collection recommendations – Teradata 14.0That will work for you.   When you copy statistics, any statistics history records that have been accumulated are retained.    When you get on Teradata Database 14.0 you want ...
36205 Feb 2014 @ 04:03 PSTcarrie's blogStatistics collection recommendations – Teradata 14.0Hi Andrew,   Age, or the passage of time, is a less accurate way of determining when statistics need recollecting compared to using the percent of change as a threshold.  Some tables ma...
36123 Jan 2014 @ 04:18 PSTcarrie's blogAutomatic Throttles in Teradata 14.0 and 14.10Review the Viewpoint Configuration Guide to make sure that the system has been correctly configured in Viewpoint and so the Viewpoint data collectors can detect the database version.  Other th...
36021 Jan 2014 @ 07:58 PSTcarrie's blogHow to Calculate Your Max Number of Usable AMP Worker TasksDas,   Changing the number of AMP worker tasks per AMP requires the modification of an internal DBS Control setting called MaxAMPWorkerTasks.  It will require a database restart.  ...
35908 Jan 2014 @ 10:49 PSTcarrie's blogAutomated Demotions on the Appliance: What are Query Milestones?Hi Geeta,   You can use RP0 for user-assigned work if you wish.   The recommendation to avoid using RP0 is made because it's usually seen as cleaner to keep internal activity t...
35806 Jan 2014 @ 04:10 PSTcarrie's blogEntering and Exiting a TASM StateSanjeev,   Your understanding is correct.  Thanks, -Carrie
35702 Jan 2014 @ 04:34 PSTDatabaseSkew-Sensitivity in the Optimizer: New in Teradata 12Santanu,   I am glad to hear you are getting a join plan that is better.   Unfortunately, I do not know all the internals about how the optimizer does its costing.  It's q...
35602 Jan 2014 @ 12:42 PSTcarrie's blogEnforcement Priority: Soft, Hard, or Just Window-Dressing?Geeta,   I think I also mentioned this in an earlier response to you on Automated Demotions on the Appliance:  What are Query Milestones?, the Appliance platform does not have work...
35502 Jan 2014 @ 12:37 PSTcarrie's blogAre AMP Worker Tasks used by FastExport in Response Mode? Velu, BTEQ sessions execute standard SQL, so the AWT usage in response mode for a request within a BTEQ session is the same as described in the first part of the blog posting above:   Un...
35402 Jan 2014 @ 11:02 PSTcarrie's blogAutomated Demotions on the Appliance: What are Query Milestones?EDW platforms with TASM and quite different from Appliance platforms.  If you are have TASM on the system, then performance periods no longer have a role.   The above comments from t...
35302 Jan 2014 @ 10:56 PSTcarrie's blogEntering and Exiting a TASM StateNot that I am aware of.  I believe those choices for default interval settings were made so that they would be reasonably well-performing.   Thanks, -Carrie
35202 Jan 2014 @ 10:38 PSTcarrie's blogCPU Limits at Multiple LevelsSanjeev,   I'm not sure I am understanding your question correctly.   When you set up "a different priority scheme" for a given planned environment, the change in priori...
35102 Jan 2014 @ 10:35 PSTcarrie's blogTASM State Changes are Streamlined in Teradata 14.0Q1:  If you have to change a rule set, it is better to do at off hours or non-busy times, as explained in the text above.   Q2:  TDWMEventHistory table shows the events that t...
35031 Dec 2013 @ 08:36 PSTcarrie's blogEnforcement Priority: Soft, Hard, or Just Window-Dressing?Response to your second question:   Enforcement priority and allocation groups no longer apply only when you move to SLES 11 operating system.  They only apply to SLES 10 priority sched...
34931 Dec 2013 @ 08:33 PSTcarrie's blogEnforcement Priority: Soft, Hard, or Just Window-Dressing?Response to your first question:   Geeta,   If you are using TASM,  workload classification criteria alone determines the workload (and thus the priority) that a query will execu...
34830 Dec 2013 @ 09:11 PSTDatabaseSkew-Sensitivity in the Optimizer: New in Teradata 12Santanu,   I cannot tell you for sure what the optimizer will choose to do. There are many considerations involved.   And even if adjustments for skew can be made wh...
34730 Dec 2013 @ 09:03 PSTcarrie's blogCPU Limits at Multiple LevelsSanjeev,   To answer your most recent question:    The calculation of the relative weight of either a resource partition or an allocation group has nothing to do with where a CPU...
34630 Dec 2013 @ 08:54 PSTcarrie's blogStatistics collection recommendations – Teradata 14.0Joe,   Your understanding is correct as to how pre-14.0 statistics collection on multiple columns work.     There are two enhancements in 14.0 that will apply here:   ...

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