SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4f23091876dba0c7c509fec2ebd9250d9d74d1277702090b213be9663871bc9' 
  AND token = 'a+TmE2Rt/ZRZWm6OWlEZjNb7G28YgaKvHEUvjIQ9kdA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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