I can't seem to declare variables within a pl/sql function?

This is a really simple question, but I can't seem to find the syntax for this anywhere.

I have something like this:

FUNCTION some_function
(
t_string IN VARCHAR2
) RETURN NUMBER IS

some_variable NUMBER;

BEGIN
//logic
END some_function;

It hits the some_variable declaration and tells me it was expecting "language" where/how do I declare variables? I've seen examples which have done it this way but for som开发者_运维技巧e reason it doesn't work.

Many thanks, Fugu

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Did not found anything wrong with your declared variable:

create or replace FUNCTION some_function
(
t_string IN VARCHAR2
) RETURN NUMBER 
IS
some_variable NUMBER;

BEGIN

return some_variable;

END some_function;

Returned NULL as expected:

select some_function('ff') from dual  

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The problem is that you don't have the CREATE OR REPLACE keywords in your function declaration, as shown in @Michael's answer.