Answer
A deadlock occurs when transactions wait on one another in a cycle and none can proceed. • Database systems detect the cycle and abort one transaction. • Applications should handle the resulting error and may retry safely. • Consistent lock ordering reduces deadlock risk.
💡 SQL Example
UPDATE accounts SET balance = balance - 10 WHERE account_id = 1;
Result
One transaction may be aborted if a wait cycle forms
⚡ Quick Revision
A deadlock is a circular lock wait resolved by aborting a participant.