Types of Locks in DB2 for Data Integrity in a Multi-User Environment

DB2 uses various types of locks to maintain data integrity in a multi-user environment. These locks help in controlling access to data and prevent concurrent transactions from interfering with each other. The main types of locks in DB2 are:

1. Shared Locks: These locks allow multiple users to read data simultaneously but prevent any user from modifying the data while it is being read.
2. Exclusive Locks: Exclusive locks restrict access to a particular data resource to only one user, preventing any other users from reading or modifying the data until the lock is released.
3. Update Locks: Update locks are used when a user intends to update a data resource. These locks prevent other users from updating the same resource concurrently, ensuring data consistency.
4. Intent Locks: Intent locks indicate the intention of a transaction to acquire a certain type of lock on a data resource. They are used to prevent deadlocks and optimize lock escalations.

By using a combination of these locks, DB2 ensures that data integrity is maintained in a multi-user environment. Each lock type plays a specific role in controlling access to data and preventing conflicts between concurrent transactions, ultimately resulting in consistent and reliable data management.