Properly Release an Advisory Lock After Use

Release an Advisory Lock

Write a PostgreSQL query to release an advisory lock acquired earlier using pg_advisory_unlock.

Solution:

-- Release the advisory lock with the specified key.
SELECT pg_advisory_unlock(12345); -- Frees the lock for others to acquire.

Explanation:

• Purpose of the Query:
• The goal is to release an advisory lock to allow other transactions or sessions to acquire it.
• This demonstrates proper cleanup of advisory locks.
• Key Components:
• pg_advisory_unlock(12345) : Releases the advisory lock identified by the key.
• Real-World Application:
• Ensures that custom locks do not persist longer than necessary, preventing resource contention.

Notes:

• Always release advisory locks after the critical section is complete.
• Failing to release locks can lead to performance bottlenecks in the application.

For more Practice: Solve these Related Problems:

• Write a PostgreSQL query to release an advisory lock with key 98765 using pg_advisory_unlock.
• Write a PostgreSQL query to release a composite advisory lock using pg_advisory_unlock with two integer parameters.
• Write a PostgreSQL query to release an advisory lock in a session after completing critical operations.
• Write a PostgreSQL query to release all advisory locks held by the current session using pg_advisory_unlock_all.

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• Master PostgreSQL Locking and Deadlock Prevention Techniques Exercises Home. ↩
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