虽然宏很好用，但它运行的速度比较慢，也不能直接运行很多WINDOWS的程序。尤其是不能自定义一些函数，这样当我们要对某些数据进行一些特殊的分析时，它就无能为力了。 由于宏具有这些局限性，所以在给数据库设计一些特殊的功能时，需要用到 模块 对象来实现
虽然宏很好用，但它运行的速度比较慢，也不能直接运行很多WINDOWS的程序。尤其是不能自定义一些函数，这样当我们要对某些数据进行一些特殊的分析时，它就无能为力了。
由于宏具有这些局限性，所以在给数据库设计一些特殊的功能时，需要用到"模块"对象来实现，而这些"模块"都是由一种叫做"VBA"的语言来实现的。使用它编写程序，然后将这些程序编译成拥有特定功能的"模块",以便在Access2000中调用。
VB,就是微软公司推出的可视化BASIC语言，用它来编程非常简单。因为它简单，而且功能强大，所以微软公司将它的一部分代码结合到OFFICE中，形成我们今天所说的VBA.它的很多语法继承了"VB",所以我们可以像编写VB语言那样来编写VBA程序，以实现某个功能。当这段程序编译通过以后，将这段程序保存在Access中的一个模块里，并通过类似在窗体中激发宏的操作那样来启动这个"模块",从而实现相应的功能。
"模块"和"宏"的使用是差不多的。其实Access中的"宏"也可以存成"模块",这样运行起来的速度还会更快呢。"宏"的每个基本操作在"VBA" 中都有相应的等效语句，使用这些语句就可以实现所有单独"宏"命令，所以"VBA"的功能是非常强大的。如果你要用Access来完成一个负责的桌面数据库系统，你就应该掌握"VBA",它可以帮你实现很多功能。但如果你只是偶尔使用一下Access或者只是用Access来做一些简单的工作，你只要简单了解一下它就可以了。
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