Database Level Locks

• A database level lock is taken on the database that the operation is operating on. While an operation holds a database level lock, no other operation that requires the same lock can operate on that database.

• A database level lock can be taken concurrently with locks on other databases in the same cluster. For example, two ALTERs can run simultaneously on two different databases.

• If a database level lock is taken, it will block a cluster lock from being taken.

• DML operations are not affected by these locks.

• DDL operations that are affected by these locks are listed in Operations that Take Database Level Locks.

• Any blocked operations will queue.

Example: Database a takes a shared lock to perform CREATE DATABASE. Database b takes a shared lock to perform BACKUP DATABASE concurrently.