Oracle无效状态错误

Question

OK guys, this error is getting real old, I get nothing from Oracle, the function will compile but gives a warning, then if I try to use it, the invalid state message. Now here is the real rub. If I 're-code' it as an anonymous program it runs fine!! So somewhere in my declaration there has to be an error, as it contains the only real difference between the Create Function and the Anonymous Program. Code for both is below, and yes I know there are easier ways to reverse a string, it is a class assignment and we cant use the built in string reverse function. Any help is appreciated!!

AS AN ANONYMOUS PROGRAM:(Note: this works fine)

 DECLARE
        strBinary             varchar2(32);
        intAnswer             number := 0;
        intExponent       number := 0;
        strReverse        varchar2(32); 
        strLength             number := 0;
        intBinChar            number := 0;
        BinChar               char;

     BEGIN
      dbms_output.enable;
        -- Reverse the Binary String first using similar function to Reversed_Name  
        strBinary := ('11111111');
        strLength := Length(StrBinary) + 1;

        FOR i IN 1..strLength   LOOP 
             BinChar := SUBSTR(strBinary,strLength-i,1);
            strReverse := strReverse || BinChar;
        END LOOP;

        --Extract the binary character from the reversed string and do the math
        FOR i IN REVERSE 1..LENGTH(strReverse)-1  LOOP
                BinChar := SUBSTR(strReverse, i, 1);
                intExponent := i - 1;
                intBinChar := TO_NUMBER(BinChar);
                intAnswer := intAnswer + (intBinChar * (2 ** intExponent));
        END LOOP;

     -- RETURN intAnswer;
        dbms_output.put_line(intAnswer);
    END;--RKC_BinToInt;

AND HERE IS THE FUNCTION THAT IS INVALID:

 CREATE OR REPLACE FUNCTION RKC_BinToInt(strBinary IN varchar2(32) RETURN number IS
        intExponent       number := 0;
        strReverse        varchar2(32); 
        strLength             number := 0;
        intBinChar            number := 0;
        BinChar               char;

     BEGIN

        -- Initialize Reverse the Binary String first using similar function to Reversed_Name  
        intAnswer := 0;
        strLength := Length(StrBinary) + 1;

        FOR i IN 1..strLength   LOOP 
             BinChar := SUBSTR(strBinary,strLength-i,1);
            strReverse := strReverse || BinChar;
        END LOOP;

        --Extract the binary character from the reversed string and do the math
        FOR i IN REVERSE 1..LENGTH(strReverse)-1  LOOP
                BinChar := SUBSTR(strReverse, i, 1);
                intExponent := i - 1;
                intBinChar := TO_NUMBER(BinChar);
                intAnswer := intAnswer + (intBinChar * (2 ** intExponent));
        END LOOP;

      RETURN intAnswer;

    END RKC_BinToInt;
    /

Answer 1

Your function should be like this

CREATE OR REPLACE FUNCTION RKC_BinToInt(strBinary IN varchar2) RETURN number IS
        intExponent       number := 0;
        strReverse        varchar2(32); 
        strLength             number := 0;
        intBinChar            number := 0;
        BinChar               char;
        intAnswer NUMBER;
     BEGIN

        -- Initialize Reverse the Binary String first using similar function to Reversed_Name  
        intAnswer := 0;
        strLength := Length(StrBinary) + 1;

        FOR i IN 1..strLength   LOOP 
             BinChar := SUBSTR(strBinary,strLength-i,1);
            strReverse := strReverse || BinChar;
        END LOOP;

        --Extract the binary character from the reversed string and do the math
        FOR i IN REVERSE 1..LENGTH(strReverse)-1  LOOP
                BinChar := SUBSTR(strReverse, i, 1);
                intExponent := i - 1;
                intBinChar := TO_NUMBER(BinChar);
                intAnswer := intAnswer + (intBinChar * (2 ** intExponent));
        END LOOP;

      RETURN intAnswer;

    END RKC_BinToInt;
    /

Answer 2

I FOUND THE ANSWER:

The problem was not with the ridiculously complex code I created to do a basic Bin to Dec conversion.

The problem was the RETURN variable intAnswer had to be declared in the Header (Create or Replace) Statement. Even though I initialized the variable in the BEGIN section of the code, the compiler did not have a handle for it. This was simply the result of some bad advice as I had asked a very experienced user if that variable had to be declared first. SO NOTE: RETURN does NOT declare a variable used within the body of a program - It worked in the Anonymous program because it was of course, declared.

Thanks for taking the time out to help all us newbies. To each and every poster on this site, you are all deserving of more than just a simple thanks for your tireless efforts.

Thanks Again Rob Campbell