By default, the table statistics are locked for all of the TSCO database schema tables. This is because the table statistics (which are used by the Optimizer to pick the best SQL Execution Plan) are maintained by the TSCO Database Space Manager system task. But there are scenarios where it is a good idea to force a refresh of the TSCO table statistics. This is particularly true: (A) After the deployment of several ETLs in a new TSCO environment where the tables have gone from empty to containing data (B) If there is a query performance problem accessing TSCO performance data and the 'Analyze Schema' hasn't been run in at least 3 months. |
You can watch this video to see how to fully refresh the TSCO database table statistics: Here is the process to run the 'Database Space Manager' in Analyze Schema mode: (1) Under Administration -> ETL & System Tasks -> System Tasks, open the 'Database Space Manager' system task. (2) Click the 'Add run configuration' button. (3) Click the 'Advanced' button. (4) In the 'Name' field enter 'Analyze Schema'. (5) Under the 'Db Manager' tab change the 'Analyze mode' from 'Auto' to 'Analyze schema'. (6) Click the 'Save' button. (7) Click the 'run this configuration' button on the same line as the 'Analyze Schema' run configuration within the 'Run configurations' section of the screen. |