SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ee7525508ed808c840767074fb067104544d1fdcc7142cb7ae7c2a5cb361b5f' 
  AND token = 'O6XQ+ZLtsIehmMATgizZAwJp4EJzOZY7P7gij9takMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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