Cleaning the backpointer table after upgrade

In Teamcenter 9.1 and later versions, relation_type object references and ImanRelation primary and secondary object references are no longer stored in the backpointer table, but are stored only in the ImanRelation table. In addition, where-referenced queries now search the ImanRelation table for ImanRelation references, rather than searching the backpointer table. These changes improve performance by significantly reducing the size of the backpointer table. To enable this performance improvement, you must run the clean_backpointer utility on your Teamcenter database after you upgrade from a version earlier than Teamcenter 9.1. The clean_backpointer utility is not run automatically during upgrade because this cleanup operation can be time-consuming. If your initial Teamcenter deployment was Teamcenter 9.1 or later, you do not need to perform this procedure. If you performed this procedure during a previous upgrade to Teamcenter 9.1 or later, you do not need to perform it again. The clean_backpointer utility scans the backpointer table for relation_type object references and ImanRelation primary and secondary object references, confirms their existence in the ImanRelation table, and deletes the instances from the backpointer table. The utility’s performance may vary, depending on infrastructure elements such as database load, network performance, server configuration, and so on. Because performance varies, Siemens Digital Industries Software recommends following these best practices: Run the utility with the -m argument set to INFO to determine whether the POM_BACKPOINTER table needs to be cleaned. (This option returns the number BACKPOINTER records to be removed.) To determine the amount of time it will take to clean the backpointer table using the CLEAN or DO_IT options, perform the operation on a backup or test system. Clean the backpointer table: Use the CLEAN option if you wish to perform the analysis just prior to cleaning the POM_BACKPOINTER table. Use the DO_IT option to clean the POM_BACKPOINTER table in the most efficient manner. To use this option, you must run the utility with the INFO option first. Caution Due to renaming of the POM_BACKPOINTER table, when running the clean_backpointer utility in CLEAN mode or DO_IT mode, make sure the system administrator has exclusive use of the system.