Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a640fa37cf8fa78cdfbe96007485444c11c12f2d3bc0d7b6214dfcd54f503e7' 
  AND token = 'D1JBoJoBa9h7KcCiNbrzWpB0ETUm+o0MQCDhrMWyFOk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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