how to performance tuning in db2

Brief introduction A connection concentrator is a new feature in the IBM DB2 Universal Database Version 8.0 (DB2 UDB) that handles a large number of inbound connections that have very short transactions but have relatively large delays. This feature has the following advantages: system resources are not occupied by connections that do not perform any work (idle connections). Because of multiplexing archi

Label:1. Top10sql "with the most execution times"DB2 "SELECT * from Sysibmadm.snapdyn_sql ORDER BY num_executions DESC FETCH first ten rows only"2, the average execution time the longest Top10sql "DB2 "SELECT * from Sysibmadm.top_dynamic_sql ORDER BY average_execution_time_s DESC FETCH first ten rows only"3, the most ranked Top10sql "DB2 "SELECT * from Sysibmadm.

One of the important issues to consider when designing a new or analyzing an existing system is the design of the application. Even if the database is well designed and optimized, application design is not appropriate or a database that can cause performance problems. Practice has shown that if there is a design problem with the application, modifying these issues can improve the performance of the applicat

Brief introduction DB2 for I5/os on V5R4 provides new ways to improve the performance of database queries through some popular dynamic SQL interfaces. The SQL call Level Interface (CLI) provides a new connection property for the user to tune the optimization target used by the database query. The Java Database connectivity (JDBC) interface for Ibm®developer kits for Java (also known as Native JDBC) and Too

Method 1: Define the appropriate referential integrity constraints between the fact table and the three dimension tables In DB2, you can define primary key and foreign key constraints to allow the database manager to enforce referential integrity constraints on the data. Referential constraints such as foreign keys also help improve performance. For example, if you modify the subexpression TMP1 in the quer