SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f89370d142e8de8629131cb93c866cdfaf4d3b5627c7aada8d514611b1370b1a' 
  AND token = '/7YWlL72Ns58joOcvqdw+rC+uJe0EJxpG+pKgrzAT38=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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