Examine this event's metadata: Now examine this command: DROP USER 'userl'e'localhost'; Which effect will the command have on the event?

Question

Options

• AThe event is scheduled and executed but fails. The system will log an error.
• BThe event is scheduled but will no longer execute. The system will log an error.
• CThe event will be dropped without an error or warning.
• DThe event is not scheduled and will no longer execute. The system will log an error.

• A
  4% (2)
• B
  74% (39)
• C
  17% (9)
• D
  6% (3)

Explanation

Option B is correct because in MySQL, an event's DEFINER determines the security context under which it runs. When DROP USER 'user1'@'localhost' is executed, the event still exists in the event scheduler (it remains scheduled), but MySQL cannot execute it because the security context - the definer - no longer exists. Each time the scheduler attempts to fire the event, it logs an error and skips execution.

Why the distractors are wrong:

• A is wrong because saying the event is "executed but fails" implies the event body actually runs; in reality, MySQL aborts before execution due to the missing definer.
• C is wrong because DROP USER does not cascade to owned events - the event is not automatically dropped; it remains in the system.
• D is wrong because the event is still scheduled (it persists in information_schema.EVENTS); it just cannot run.

Memory tip: Think of the DEFINER as the event's "ID badge." The event stays on the schedule board (scheduled), but without a valid ID badge (definer), it's turned away at the door every time it tries to run, and security logs the incident (error log).

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