php database ai_generated true

SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock; try restarting transaction

ID: php/database-deadlock

Also available as: JSON · Markdown
83%Fix Rate
87%Confidence
65Evidence
2023-01-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
83 active — — —

Root Cause

Database deadlocks occur when two or more transactions hold locks that each other needs, creating a circular wait. MySQL automatically detects this and rolls back one transaction. The fix involves consistent lock ordering, shorter transactions, and retry logic.

generic

Workarounds

  1. 90% success Implement automatic retry logic for deadlocked transactions 
    Wrap the transactional code in a retry loop that catches SQLSTATE 40001 and retries the entire transaction up to 3 times with a short random delay. In Laravel, use DB::transaction($callback, 3) which has built-in retry support.
  2. 85% success Access tables and rows in a consistent order across all transactions 
    Ensure all code paths that modify the same tables acquire locks in the same order (e.g., always update table A before table B). Use SELECT ... FOR UPDATE with ORDER BY to lock rows in a deterministic order.

Dead Ends

Common approaches that don't work:

  1. Increasing innodb_lock_wait_timeout to avoid the error 75% fail

    Lock wait timeout and deadlock detection are different mechanisms. Increasing the timeout only delays the inevitable and causes longer request hangs. The deadlock will still be detected and one transaction rolled back.

  2. Wrapping every query in a separate transaction to avoid conflicts 70% fail

    Using one transaction per query loses atomicity guarantees and can leave data in an inconsistent state. It also doesn't prevent deadlocks since the issue is about lock ordering across concurrent requests.

Error Chain

Leads to:
Preceded by:
Frequently confused with: