Use bind variables inside pl/sql stored procedure - oracle

Question

Is it possible to use bind variables,(declared and initialized outside pl/sql block) inside pl/sql stored procedure
I am just trying to print bind variable defined as shown below :
Bind variable declaration and initialization
var jdata varchar2(4000);
exec :jdata := ''{"PONumber":12,"Reference":"StackOver"}'';
pl/sql procedure
create or replace PROCEDURE generic_procedure( v_typename IN VARCHAR2,v_path IN VARCHAR2 DEFAULT '$') IS
BEGIN
dbms_output.put_line(:jdata);
END generic_procedure;
/
Error
fails at compilation:
SQL> show errors
Errors for PROCEDURE GENERIC_PROCEDURE:
ERROR: bad bind variable 'JDATA'
Here, I'm trying to call jdata inside generic_procedure(stored pl/sql procedure) . but it says JDATA as
bad bind variable

Answer 1

You could use a substitution variable:
define jdata='{"PONumber":12,"Reference":"StackOver"}';
create or replace PROCEDURE generic_procedure( v_typename IN VARCHAR2,
v_path IN VARCHAR2 DEFAULT '$') IS
BEGIN
dbms_output.put_line('&jdata');
END generic_procedure;
/
But you can also pass it as a parameter to the procedure. Which seems a bit cleaner to me. Since the procedure does not depend on some variable that has, or has not been, declared outside of it. It just works on the parameters alone.
create or replace PROCEDURE generic_procedure( v_data IN varchar2,
v_typename IN VARCHAR2,
v_path IN VARCHAR2 DEFAULT '$') IS
BEGIN
dbms_output.put_line(v_data);
END generic_procedure;
/
exec generic_procedure('&jdata','typename');
Here's some more about variables in sqlplus

Answer 2

AFAIK, don't think this is possible as the PL/SQL variables need to be defined in the scope of the package or procedure.
You can create a package to hold this variable and then set and use it's value in the procedure.
CREATE OR REPLACE PACKAGE P_test
is
jdata CONSTANT varchar2(4000):=''{"PONumber":12,"Reference":"StackOver"}'';
END P_test ;
create or replace PROCEDURE generic_procedure( v_typename IN VARCHAR2,v_path
IN VARCHAR2 DEFAULT '$') IS
BEGIN
dbms_output.put_line(P_test.jdata);
END generic_procedure;
Hope it helps
Vishad