Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df1b393b1468fe7cc5f2cf7d95742926999586a3ec0984f92ed18ff6f4eddd5d' 
  AND token = 'F9m3ztNXVn8C85If/4+aHhZa8Kks+KcBI1//iQMT7wI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}