SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47e327b19749a1996e5af74276c17ebbfb7373f58b97d849d0ac062b071dd527' 
  AND token = 'Bg5CblJ7PX6e0AU1B7fDYksERtck08HvUHGoFzCrxmk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00081

JSON explain

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