SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '426a098e605f08c60f2b7a6d46c6c9e7e99302ff9843f161e34cd42cb53b452d' 
  AND token = 'f3IxB86NojsKBdRX4O2oSn9dJEB+lbNRUn5rUPJUA70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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