IBM DB2 Manual page 525

v DB2 Command Reference, which explains how to run commands
If you will be using data sharing, you need DB2 Data Sharing: Planning and
Administration, which describes how to plan for and implement data sharing.
Additional information about system and database administration can be found in
DB2 Messages and DB2 Codes, which list messages and codes issued by DB2, with
explanations and suggested responses.
Diagnosis
Diagnosticians detect and describe errors in the DB2 program. They might also
recommend or apply a remedy. The documentation for this task is in DB2 Diagnosis
Guide and Reference, DB2 Messages, and DB2 Codes.
509
How to use the DB2 library