local nested class (局部嵌套類): 局部嵌套類定義在 enclosing class 的方法里面,局部嵌套類有enclosing class 屬性和enclosing method 屬性 anonymous nested class(匿名嵌套類):匿名嵌套類沒有顯示的定義一個類,直接通過new 的方法創(chuàng)建類的實例。一般回調模式情況下使用的比較多 ...
It's pretty simple to make two separate updates, but by enclosing them within the PDO::beginTransaction() and PDO::commit() calls, we are guaranteeing that no one else will be able to see those changes until they are complete. If something goes wrong, the catch block rolls back all ...