编写Oracle包中的函数应当注意的两点问题
自己刚开始用PL/SQL来写一点东西，现在还肤浅的很，说这些不是想谦虚，而是想如果有高手看到自己有什么地方写错的，希望给我一点指点。 今天下午找了一下午自己的那个PL/SQL包的错误，最后还是解决了。。。两个小的不能再小的问题，和大家分享一下。 1、在PL
自己刚开始用PL/SQL来写一点东西，现在还肤浅的很，说这些不是想谦虚，而是想如果有高手看到自己有什么地方写错的，希望给我一点指点。
今天下午找了一下午自己的那个PL/SQL包的错误，最后还是解决了。。。两个小的不能再小的问题，和大家分享一下。
1、在PL/SQL中如果是函数，就可以SQL语句中使用，也可以在其他的PL/SQL程序段中使用。但是在程序段中使用的话就一定要注意了，必须要接收函数的返回值。要不然PL/SQL会认为这个函数是一个过程，而返回参数类型不正确的错误。
如：function add_two_num(num1 in number,num2 in number)return number这样的函数，调用的时候即使你不使用这个返回值也要用num3:=add_two_num(num1,num2);的形式，不能使用add_two_num(num1,num2)的形式。呵呵，有时我们会用到out类型的变量，可能会出现这种情况。
2、在包头中定义函数和包体中实现函数时变量的名称一定要一样，否则会提示包头中的某个函数没有定义，如：在包头中定义function add_two_num(num1 in number,num2 in number)return number;在包体中实现时你只实现了function add_two_number(num3 in number,num2 in number);时就会出现错误，这个也不难想到，想一下在PL/SQL中有几种调用函数的方法你就会对这个设置的意义很明了了。。。
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