#DateWhereItemComment
52002 Nov 2015 @ 11:23 PSTcarrie's blogA Closer Look at How to Set up a Parsing-Only WorkloadGeeta,   There is an explanation for what you are seeing.   Both Stored procedure CALL statements and Check Workload For statements are handled differently from other statements. ...
51930 Oct 2015 @ 09:25 PDTcarrie's blogStatistics Collection Recommendations – Teradata 14.10, 15.0 and 15.10Nazy,   I have not heard of any issues with USECOUNT logging overhead being problematic. USECOUNT logging uses the same techniques as other DBQL collections. There is a USECOUNT DBQL cache t...
51830 Oct 2015 @ 08:58 PDTcarrie's blogStatistics Collection Recommendations – Teradata 14.10, 15.0 and 15.10Genner,   Statistics for volatile tables (VTTs) are handled differently from statistics on base tables.  Statistics collected from VTTs  are not saved in DBC.StatsTbl. They are sav...
51728 Oct 2015 @ 04:38 PDTcarrie's blogNew opportunities for statistics collection in Teradata 14.0Statistics  on volatile tables are not saved in DBC.statstbl, as are other statistics on base tables.  Volatile table stats are saved in memory for the given session.   Currently, ...
51627 Oct 2015 @ 09:47 PDTcarrie's blogStatistics Threshold Functionality 101Zarrar,   If you wish to ignore the default global threshold capability (or your own established threshold percent or number of days) for just a single statistics collection statement, you c...
51526 Oct 2015 @ 10:19 PDTDatabaseSkew-Sensitivity in the Optimizer: New in Teradata 12Hi Sam,   My best guess about why you are spooling out is that you have a large skew issue somewhere in one of the spool files lower in the plan.   When there are large numbers of ...
51426 Oct 2015 @ 09:03 PDTcarrie's blogStatistics Collection Recommendations – Teradata 14.10, 15.0 and 15.10Dinesh,   The stats collection operation uses an access lock on the table and can be run when that table is being read or updated by a query.  You can see this access lock if you do an ...
51317 Oct 2015 @ 12:40 PDTcarrie's blogUtility Session Management - It's Inside the Database in Teradata 13.10! (UPDATED)If you mean that you have a system utility throttle for TPT Update jobs (MultiLoad), but some sessions are being delayed, first find out what throttle is causing the delay.   Some sessions w...
51212 Oct 2015 @ 10:17 PDTDatabaseTo Peek or Not to Peek, That is the QuestionGeeta,   Empty space in the DBQL CacheFlag field means that the request did not have parameterized SQL and therefore was not eligible for using a cached plan.    All queries w...
51125 Sep 2015 @ 11:37 PDTcarrie's blogUtility Session Management - It's Inside the Database in Teradata 13.10! (UPDATED)TPT Stream will not use a utility slot.  TPT Stream operator and it's predecessor, TPump, use SQL-based load approaches and therefore do not tie up resources to the degree that TPT Load (F...
51022 Sep 2015 @ 09:08 PDTcarrie's blogA Closer Look at How to Set up a Parsing-Only WorkloadGeeta,   If you are sure that every user has a profile, then there is no down side of including Profile =  * in your classification.   It is only a problem if a user has no pr...
50918 Sep 2015 @ 04:25 PDTcarrie's blogA Closer Look at How to Set up a Parsing-Only WorkloadGeeta,   I am sorry you are still having problems with this.   I'm still somewhat concerned about your dummy classification on query characteristics.  You want to make the qu...
50817 Sep 2015 @ 04:42 PDTcarrie's blogA Closer Look at How to Set up a Parsing-Only WorkloadGeeta,   Try redefining the POW workload classification without the Profile=* part.  Unless you are 100% sure that all your users have profiles, it could be problematic in this case. &...
50711 Sep 2015 @ 08:29 PDTcarrie's blogHow Resources are Shared in the SLES 11 Priority SchedulerPierre,   The mapping of a query to a workload will be determined by two things: 1.  The classification criteria defined on the workload 2.  The session and query characteristics...
50608 Sep 2015 @ 08:39 PDTcarrie's blogAutomatic Throttles in Teradata 14.0 and 14.10Yes, you can do that.   Thanks, -Carrie
50504 Sep 2015 @ 01:22 PDTcarrie's blogAutomatic Throttles in Teradata 14.0 and 14.10Teraboy,   There are a couple of questions here.   1.)  The most likely reason you received that error message regarding a ruleset version not being compatible is that the "...
50403 Sep 2015 @ 11:44 PDTcarrie's blogTeradata Basics: ParallelismMukal,   Could I ask in the future that you post questions and/or comments under blog postings that are relevant to the topic you are asking about?   It can get confusing...
50301 Sep 2015 @ 04:27 PDTcarrie's blogStatistics collection recommendations – Teradata 14.02% sampling should fine fine for a UPI column.  Sampling at low percentages is fairly accurate for any column that is unique or nearly-unique.   Unfortunately, there is no way I know of...
50228 Aug 2015 @ 09:52 PDTcarrie's blogStatistics collection recommendations – Teradata 14.0Arpit,   USING SAMPLE specified on a collect statistics statement does not necessarily result in sampling taking place.   It means you are letting the optimizer decide whether or n...
50127 Aug 2015 @ 04:07 PDTcarrie's blogRecommended Dictionary Statistics to Collect in Teradata 14.0Atul,   Dictionary stats usually take only a couple of minutes to collect, as the tables tend to be small.  And you do not need to recollect them very often.  I am not aware of any...
50025 Aug 2015 @ 07:54 PDTcarrie's blogStatistics Collection Recommendations – Teradata 14.10, 15.0 and 15.10I don't have a list of DBC stats recommendations focused especially on the 15.0 release.  What you can do is use the recommendations in the  blog posting for collecting stats on the d...
49925 Aug 2015 @ 07:51 PDTcarrie's blogIntrepreting DBQL DelayTime in Teradata 13.10I am not familiar with "Responding State" as it appears in Viewpoint.  You would have to ask that question of someone who has more extensive knowledge of Viewpoint porlets....
49824 Aug 2015 @ 08:45 PDTcarrie's blogTwo Levels of Concurrency Control for Load Utilities in Teradata 13.10For load utilities all work between the BEGIN WORKLOAD and END WORKLOAD are considered to be a Unit Of Work (UOW).  When a BEGIN WORKLOAD is received the UOW is defined and classified. All wor...
49724 Aug 2015 @ 08:44 PDTcarrie's blogRequest Cache Hits & MissesPierre,   YOUR QUESTION:  How does the optimizer recognize a "query" as being already in cache from another query being not ?   Strictly speaking it is request (a reque...
49618 Aug 2015 @ 08:42 PDTcarrie's blogRequest Cache Hits & MissesPierre, Executing queries by themselves will not cause the request cache to be spoiled.  (By "spoiling" I mean selectively removing entries, in contrast to "purging" ...

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