SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '962565c8cf2ccbeaac78d924369103c569c568a243429727c8b141b250622f80' 
  AND token = 'KRcnbNndqjvN3WuShYtfxLqoGGc1JVt7+HXW8YmiHTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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