Package Errors. What Am I doing wrong? - sql

Question

I'm trying to create a package that works out the number of days between two dates, I'm aware I have probably got this miles wrong, I am really struggling to troubleshoot this. My knownledge is low on oracle, I'm still quite new to this. The package I've written is below, but I am getting the error shown at the bottom.
How do I resolve this?
CREATE OR REPLACE PACKAGE PACKNAME
AS
FUNCTION TIME_SCALE RETURN NUMBER;
END;
/
CREATE OR REPLACE PACKAGE BODY PACKNAME
AS closed_date := '28-APR-14'
FUNCTION TIME_SCALE RETURN NUMBER;
IS BEGIN
TRUNC(mrc.closed_date - mrc.open_date) AS days_difference FROM TASKS mrc;
END;
​
Error at line 2: PLS-00103: Encountered the symbol "=" when expecting one of the following: constant exception <an identifier> <a double-quoted delimited-identifier> table long double ref char time timestamp interval date binary national character nchar
I have substituted some of the names to make them clearer for you to read.
The function is to output the number of days it has taken for a task to be completed. The columns basically include the date_opened and date_closed in simple terms as well as a few others and a unique ID which I believe is a sequence.

Answer 1

Try this:
CREATE OR REPLACE PACKAGE PACKNAME
AS
FUNCTION TIME_SCALE
RETURN NUMBER;
END;
/
CREATE OR REPLACE PACKAGE BODY PACKNAME
AS
closed_date VARCHAR2(50):= '28-APR-14';
days_difference NUMBER;
FUNCTION TIME_SCALE
RETURN NUMBER
IS
BEGIN
SELECT TRUNC(mrc.closed_date - mrc.open_date) INTO days_difference
FROM TASKS mrc;
RETURN days_difference;
END;
END;
What was wrong:
1) You have missed the type for closed_date
2) You had an ';' after RETURN NUMBER in function declaration
3) You have missed SELECT clause inside function
4) You have missed END for the package