Comments on: understanding and detecting sql performance situation with abnormal 400 shutdown http://itknowledgeexchange.techtarget.com/itanswers/understanding-and-detecting-sql-performance-situation-with-abnormal-400-shutdown/ Sat, 28 Nov 2009 10:49:30 +0000 http://wordpress.org/?v=2.6.2 By: BigKat http://itknowledgeexchange.techtarget.com/itanswers/understanding-and-detecting-sql-performance-situation-with-abnormal-400-shutdown/#comment-64271 BigKat Fri, 05 Jun 2009 17:16:33 +0000 #comment-64271 It is also possible that you have crossed some magic combination of number of records, etc, that now causes the query analyzer to build a different (and less efficient) plan It is also possible that you have crossed some magic combination of number of records, etc, that now causes the query analyzer to build a different (and less efficient) plan

]]> By: Graybeard52 http://itknowledgeexchange.techtarget.com/itanswers/understanding-and-detecting-sql-performance-situation-with-abnormal-400-shutdown/#comment-64253 Graybeard52 Fri, 05 Jun 2009 02:24:44 +0000 #comment-64253 Two things that will simply kill you on SQL performance: 1. Writing a query over a logical file. 2. Writing a query over a PF where ANY logical has select/omit or other derived keys, unless QAQQINI has been told to ignore derived indexes (default is to NOT ignore). Otherwise, try deleting the SQL packages and let the system rebuild them. Two things that will simply kill you on SQL performance:
1. Writing a query over a logical file.
2. Writing a query over a PF where ANY logical has select/omit or other derived keys, unless QAQQINI has been told to ignore derived indexes (default is to NOT ignore).

Otherwise, try deleting the SQL packages and let the system rebuild them.

]]> By: Cwc http://itknowledgeexchange.techtarget.com/itanswers/understanding-and-detecting-sql-performance-situation-with-abnormal-400-shutdown/#comment-64205 Cwc Thu, 04 Jun 2009 13:24:26 +0000 #comment-64205 You can also use the database monitor from a command line (STRDBMON), to see why the query engine is rejecting that index. You can also use the database monitor from a command line (STRDBMON), to see why the query engine is rejecting that index.

]]> By: Modiyooch http://itknowledgeexchange.techtarget.com/itanswers/understanding-and-detecting-sql-performance-situation-with-abnormal-400-shutdown/#comment-64178 Modiyooch Wed, 03 Jun 2009 15:21:52 +0000 #comment-64178 yes, we had a normal shutdown and restart after the failure. The only indication of a problem other than poor program performance was that a lf with heavy usage had not been used since the initial failure. I was just hoping to better identify this situation without finding out from the users when their programs become grossly inefficient. thanks for the input yes, we had a normal shutdown and restart after the failure. The only indication of a problem other than poor program performance was that a lf with heavy usage had not been used since the initial failure. I was just hoping to better identify this situation without finding out from the users when their programs become grossly inefficient. thanks for the input

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