Advisory Locks

Problem

You want to write a distributed lock in PostgreSQL to ensure only one worker runs a clean-up cron job, without locking any table rows. Write a query that outputs concept with the value: "Advisory locks are application-defined database locks that do not lock actual table rows, useful for distributed application locking."

Database Schema

This problem acts as a scratchpad. You will write your own DDL/DML or conceptual queries, so there is no predefined schema.

Try It

Hint

Solution