Bind variable inside a package

Question

Can we declare a bind variable inside a package specification?
CREATE OR REPLACE PACKAGE GET_EMPLOYEEDETAILS
IS
PROCEDURE GET_FIRSTNAME(E_ID IN EMPLOYEES.EMPLOYEE_ID%TYPE, F_NAME OUT EMPLOYEES.FIRST_NAME%TYPE);
VARIABLE O VARCHAR2(20);
END GET_EMPLOYEEDETAILS ;
CREATE OR REPLACE PACKAGE BODY GET_EMPLOYEEDETAILS
IS
PROCEDURE GET_FIRSTNAME(E_ID IN EMPLOYEES.EMPLOYEE_ID%TYPE, F_NAME OUT EMPLOYEES.FIRST_NAME%TYPE)
IS
BEGIN
SELECT FIRST_NAME INTO F_NAME FROM EMPLOYEES WHERE EMPLOYEE_ID = E_ID;
DBMS_OUTPUT.PUT_LINE(F_NAME);
END;
END GET_EMPLOYEEDETAILS;
Output:
ERROR at line 4: PLS-00103: Encountered the symbol "VARCHAR2" when expecting one of the following:
  := . ( @ % ; not null range default character
The symbol ":=" was substituted for "VARCHAR2" to continue.
2. IS
3. PROCEDURE GET_FIRSTNAME(E_ID IN EMPLOYEES.EMPLOYEE_ID%TYPE, F_NAME OUT EMPLOYEES.FIRST_NAME%TYPE);
4. VARIABLE O VARCHAR2(20);
5. END GET_EMPLOYEEDETAILS ;
6. /
or is there any alternative for bind variables inside an package
Thanks in advance
Message was edited by: 1009739

Answer 1

The "VARIABLE O VARCHAR2(20);" syntax is the way SQLPlus declared bind variables - it is specific to the client. Because PL/SQL packages and procedures are server code that continue past sessions, its only access to the client environment is what the client gives it - it can't go and create a bind variable in the client.
PL/SQL procedures, functions and packages run from lots of environments, so they cannot access bind variables inside their body - you have to pass any external variables as parameters.
Anonymous PL/SQL blocks can access bind variables.
You can declare package public global variables - just leave out that "VARIABLE". E.g.
CREATE OR REPLACE PACKAGE GET_EMPLOYEEDETAILS
IS
PROCEDURE GET_FIRSTNAME(E_ID IN EMP.EMPNO%TYPE, F_NAME OUT EMP.ENAME%TYPE);
O VARCHAR2(20);
END GET_EMPLOYEEDETAILS ;
For local variables in your procedure, just put them between the IS and BEGIN. Using them in SQL inside the PL/SQL automatically uses them as a bind variable.
create or replace PROCEDURE GET_FIRSTNAME(E_ID IN EMP.EMPNO%TYPE, F_NAME OUT EMP.ENAME%TYPE)
IS
  O VARCHAR2(20);
  O2 VARCHAR2(21);
BEGIN
  O := 'FR%';
SELECT ENAME INTO F_NAME FROM EMP WHERE EMPNO = E_ID and ENAME like O;
O2 := F_NAME || '2';
DBMS_OUTPUT.PUT_LINE(F_NAME);
END;
O is bound in the query.
To access bind variables from anonymous PL/SQL, first declare them in the calling environment. In SQL Plus that's
VARIABLE O VARCHAR2(20);
In Pro*C it's
EXEC SQL BEGIN DECLARE SECTION;
  char[21] O
EXEC SQL END DECLARE SECTION;
Then reference it in anonymous PL/SQL with a colon as prefix:
BEGIN
SELECT FIRST_NAME INTO :O FROM EMPLOYEES WHERE EMPLOYEE_ID = E_ID;
END;
This only works for anonymous blocks (starting with BEGIN or DECLARE). As I said, PL/SQL procedures, functions and packages cannot see bind variables from the calling environment