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Deadlock Recovery

Mission brief

Challenge Briefing

Easy

COUNT()
Filtering

Random transaction failures are plaguing the production database, and the DevOps team suspects a series of deadlocks. Your task is to investigate the database_logs and determine exactly how many times the "lock_wait_timeout" event occurred.

Deadlock Recovery

Count the exact number of database lock timeout events.

The Narrative

Schema Diagram

database_logs

idINT

event_typeVARCHAR

timestampDATETIME

Challenge a Friend

One SQL table. One SQL condition.
Still tricky for most developers.

SQL Editor

Terminal Output

Initializing Database Engine v1.8.0...

Write a SQL query, then click Run Query

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