Reorg is rearranging the rows according to the clustering order while preserving free space and reusing space. These actions usually improve access performance, especially when the access depends on clustering. It is also important to be pro-active and identify critical conditions that may affect availability if an object is running out of space or reaching its maximum size. The DB2 administrator spends time and effort in identifying those specific objects that require REORG to avoid performance and availability problems. TUC automates the process, identifies automatically objects for reorg, generates and executes the reorg jobs.
DB2 collects Real Time Statistics that can be used to identify the rate of changes since the last REORG. TUC allows you to define rules to examine Real Time Statistics and catalog statistics and qualify objects for REORG execution. REORG jobs can be automatically triggered and handed over to a scheduler to REORG only the selected objects. TUC processes the indexes explicitly only if the associated tablespace partition was not selected for REORG.
TUC allows you to define priorities based on the condition of each object. This way objects in critical condition can be processed first. For example, a tablespace with 200 extents should be processed before an object with 50 extents. You can also define a quota of objects or total size to process only a limited number of objects.
Traditionally, it was common to collect statistics from time to time to ensure the DB2 optimizer has the most current statistics required to choose the best access path for better performance. However, collecting statistics blindly might be expensive if the data has not changed dramatically or has not grown. Real Time Statistics can be used to identify the rate of changes since the last RUNSTATS. TUC exploits RTS and triggers statistics collection only if the statistics are indeed outdated. In addition, with RTS you may no longer rely on catalog statistics to identify which objects require REORG and you can afford to collect statistics only for the usage of the DB2 optimizer.
Small tables are easier to maintain and access. You can decrease the size of your tables by archiving or purging old data. TUC automates the generation of the REORG DISCARD utility and allows you to easily purge or archive old data from your DB2 tables. This way you can trim down critical tables and improve access performance. TUC records the discarded flat files and allows you to easily reload or recall the data when needed.
TUC allows you to define the discard conditions for each table and has the appropriate REORG DISCARD statements generated for each tablespace. TUC extends the functionality of discard conditions by allowing you to use a discard query. The results of the discard query can be used to generate the required discard conditions. You can also imbed symbols in discard conditions that are resolved at runtime based on user provided values.
CHECK DELETE can also be used to remove dependent rows from discarded tables. Exceptions tables for all dependent tables are created automatically in a special exceptions database. Exceptions tables can also be dropped automatically when empty or when expired.
To better manage your allocated space, you can estimate the maximum number of expected rows for each table. TUC automatically corrects the estimated number of rows when it is exceeded by the actual number of rows in the table. TUC also automates the process of identifying tables with compression benefits. Compressed tables require less DASD space, less log space, less backup space and shorter backup time. TUC calculates space using the provided estimates and alters space allocation and compression prior to REORG.
TUC automates the generation and execution of DB2 utilities and allows you to handle your DB2 maintenance efficiently. TUC automation helps saving resources and cutting down expensive maintenance tasks while ensuring full recoverability and availability. TUC allows you to cut the cost of backups, REORG and statistics collection by using Real Time Statistics. [/slider]