SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d70a2d010ce253431119d71b17ed01234684c2fc31ede8bbd4e35c698ecd42c' 
  AND token = '4cGR9q5y/cJGuugXZIvqPxLxq6lITn67MOanrmJ9Dbc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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