What is Db2 performance tuning?

What is Db2 performance tuning?

Performance tuning using the Db2 Process Model It basically follows a path similar to all database performance diagnostic processes: Identify the bottleneck or problem. Collect statistics about the affected area. Apply the statistics to the Db2 Process Model. Take the corrective action.

How can I improve my Db2 query performance?

Ways to improve query performance

  1. Scan the PARTS table for every row that matches a row in the PRODUCTS table.
  2. Scan the PRODUCTS table for every row that matches a row in the PARTS table.
  3. Sort both tables in PROD# order; then merge the ordered tables to process the join.

What is DBD in Db2?

DBD::DB2 is a Perl5 module which when used in conjunction with DBI allows Perl5 to communicate with IBM’s DB2 Universal Database.

What is RTS in Db2?

Db2 updates its in-memory real-time statistics (RTS) counters for SQL operations such as INSERT, DELETE, and UPDATE, and externalizes the values to the RTS tables in the catalog at a specified interval and for certain events.

What is null indicator in DB2?

The null indicator is used by DB2 to track whether its associated column is null or not. A positive value or a value of 0 means the column is not null and any actual value stored in the column is valid.

How do I tune a SQL query in Db2?

SQL Tuning for Db2 – Where to Start by Eddy Coppens

  1. Keep it simple.
  2. Understand what you are about to do.
  3. Know your data.
  4. Know your SQL.
  5. Check database statistics for queries already in use.
  6. Some examples:

What is optimize for 1 row in Db2?

OPTIMIZE FOR 1 ROW tells Db2 to select an access path that returns the first qualifying row quickly. Use FETCH FIRST n ROWS ONLY clause to limit the number of rows in the result table to n rows.

What is Db2 directory?

The Db2 directory contains information that Db2 uses during normal operation. You can use SQL to retrieve data only from the directory tables that are listed in Db2 directory tables. You can submit queries against the Db2 catalog for Db2 directory objects.

What are the mandatory components of Db2?

The complex DB2 internal structure has been divided into 5 major components / Address Spaces:

  • System Services component / System Services Address Space (Job: DSN1MSTR)
  • Locking Services component/ Locking Services Address Space (Job: IRLMPROC)
  • Database Services component/ Database Services Address Space (DSN1DBM1)