Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3a8cb7f7d549e52ee0c3275764cc564d2d8aa24e57eadbe2ad264b0553db56e' 
  AND token = 'Ad8wmVN4URiyFbM9Dt9WzOqUQl7Y4n5yq7LFcGvFXfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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