帮我写一个最简单的函数！谢谢！

[lynx800602]

输入两个参数：除数和被除数返回商，要求有异常处理。数字要一定精度
谢谢！

[yfjyz]

create or replace function div(a number, b number) return number
as
begin
if b=0 then
begin
Raise_Application_error(-20001, '除数不能为0');
return 0;
exit;
end;
return (a/b);
end;

[LGQDUCKY]

create or replace function div(a number, b number) return number
is
ret number;
begin
begin
ret : a/b;
EXCEPTION
WHEN OTHERS THEN
Raise_Application_error(-20001, '除数不能为0');
return -1;
end;
return ret;
end;
/

[beckhambobo]

create or replace function div(a number, b number)
return number
is
ret number;
begin
ret := a/b;
return ret;
EXCEPTION
WHEN OTHERS THEN
return -1;
end;
/

[robixiao]

I suggest one point as below:
ret := cast(a/b as decimal(10,3));

[lynx800602]

to: LGQDUCKY(飘)
创建：
(a number, b number) return number
is
ret number;
begin
begin
ret:=a/b;
EXCEPTION
WHEN OTHERS THEN
Raise_Application_error(-20001, '除数不能为0');
return -1;
end;
return ret;
end;

运行：
declare
div2 number;
begin
div2:=DIV(8,0);
dbms_output.put_line(div2);
end;

出错：
declare
*
ERROR 位于第 1 行:
ORA-20001: 除数不能为0
ORA-06512: 在"TEST.DIV", line 9
ORA-06512: 在line 4

---------------------------------------------------
to:beckhambobo(beckham)运行成功
但是能不能在除数为零时返回空值并打印“除数不能为0”
---------------------------------------------------
to:yfjyz(dd) 便已有错误：
行号= 11 列号= 4 错误文本= PLS-00103: 出现符号 ";"在需要下列之一时： if
---------------------------------------------------
还要问一句Raise_Application_error(-20001, 从哪来的？

[LGQDUCKY]

create or replace function div(a number, b number)
return number
is
ret number;
begin
if b = 0 then
return 0;
end if;
ret := a/b;
return ret;
EXCEPTION
WHEN OTHERS THEN
return -1;
end;
/