SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f7bb0c8aa044905674e707966d2833f27b9c4e9cde153ebed0338dc74a2b01d' 
  AND token = 'orpIJzvJoVZkdv0KxbtQnXP2+xOwIh4/V1LsueFlrP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}