Chapter 11

A1: Increasing MAXLOCKS (the percentage of the lock list that an application can use before escalation occurs) and increasing LOCKLIST can reduce the chances of getting lock escalations.
A2: When a user performs a read operation, by default DB2 attempts to lock the rows with share locks. Once a share lock is acquired, concurrent users will not be able to make changes to the rows. However, concurrent read is allowed. In this example, Sam may have set the isolation level as UR, so DB2 will not acquire any row lock. This may result in uncommitted data within the same transaction as described here.
A3:
Databases:CONNECT TO dbname IN EXCLUSIVE MODE
Table spaces:QUIESCE TABLESPACE FOR TABLE tabname INTENT FOR UPDATE
Tables:LOCK TABLE tabname ...

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