SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08001d9fc44b3b257ee2b53d921b34c64528dc98a682312f71c06ad6f8de9600' 
  AND token = 'jfdh9Q6fRQEzFymtXS52o00QsBmpZQP3pie+UmTmR+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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