{
  "format": "mysql-lab-oncall/v1",
  "recorded_at": "2026-11-13T18:10:26.913264+00:00",
  "environment": {
    "version": "8.4.13",
    "schema_name": "mysql_lab",
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    "deadlock_detect": 1
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    "locking_roster": "SELECT doctor_id FROM oncall_roster WHERE shift_id=1 AND on_call=1 ORDER BY doctor_id FOR UPDATE",
    "leave": "UPDATE oncall_roster SET on_call=0 WHERE shift_id=1 AND doctor_id=%s AND on_call=1"
  },
  "ddl": [
    "CREATE TABLE IF NOT EXISTS oncall_guard (shift_id INT PRIMARY KEY) ENGINE=InnoDB",
    "CREATE TABLE IF NOT EXISTS oncall_roster (shift_id INT NOT NULL, doctor_id INT NOT NULL, on_call TINYINT NOT NULL, PRIMARY KEY(shift_id,doctor_id), CHECK(on_call IN (0,1))) ENGINE=InnoDB"
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          "on_call": 0
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    "remaining_lab_locks": 0,
    "workers_joined": true,
    "sessions_closed": true
  }
}