CA ERwin Model Manager Implementation Guide

Run the Database StatisticsTroubleshooting the Reindexing ScriptIf your query tool responds:no rows selectednot spooling currentlyit means you do not have the correct name for the CA ERwin MMschema-owner. You must get the correct user name, replace 'MODELMART'with the user name, and re-run the script.Run the Database StatisticsDatabase statistics show the distribution of the data in the database, and howthe data is stored. When a database executes a query, it uses an optimizer todetermine the best path to access the data. The optimizer relies on executionplans that specify the order in which the database accesses the tables and theexact steps used to pull the data. The database bases the creation of theexecution plans on the database statistics.As the data grows and changes, the statistics quickly become outdated and nolonger reflect the true condition of the database. As a result, the executionplans no longer apply and the optimizer makes poor decisions when processingqueries. You should run statistics regularly to ensure the maximumperformance of your database and, therefore, your CA ERwin MM mart. Werecommend that you run the database statistics nightly, and create anautomated batch job to simplify the process.Example: Statistics Commands (Oracle)NOTE: In the examples below, the schema owner name is 'MODELMART'To collect statistics for the CA ERwin MM (does not include the indexstatistics):EXEC DBMS_STATS.gather_schema_stats ('MODELMART',DBMS_STATS.AUTO_SAMPLE_SIZE);To collect statistics for the CA ERwin MM (includes the index statistics):EXEC DBMS_STATS.gather_schema_stats (ownname => 'MODELMART',cascade =>true, estimate_percent => dbms_stats.auto_sample_size);To delete the statistics:EXEC DBMS_STATS.delete_schema_stats ('MODELMART');Appendix C: CA ERwin MM Performance 75