Practise · Real PostgreSQL
SQL lab
Use real SQL to complete a guided task in a temporary PostgreSQL database. Your lab is isolated from every other learner and is removed when you finish or when it expires.
Your goal
Identify the root blocking transaction, its owner and impact, then use the least disruptive safe intervention.
What to do
- Start your temporary database.
- Read the task and run SQL in the workspace.
- Check your work. The server will inspect the database state.
- When every task passes, continue to the assessment.
Managed PostgreSQL workspace
Real SQL lab
A queue worker appears stuck. You must understand which lock protects the row before deciding whether to wait or intervene.
Your database is temporaryIt is private to this lab and deleted when you finish or it expires.
Goal
Inspect a blocking relationship, choose the correct session to address, and make a lock-sensitive update safely.
Start when you are ready. Creating your private database can take a few seconds. You do not need a Neon account.