How to compare two variables in IF statement? - if-statement

Question

I am trying to execute the below query.
I am trying to do this comparison using IF statement. I am expecting my result to like the values which are not in v_anwen_id should be selected from v_anwen2_id. so when v_anwen2_id is not equal to v_anwen_id then to execute the insert statement. But i am not getting the " v_anwen2_id is not equal to v_anwen_id " value. ( i wanted it to be like when a is not equal to b then execute insert statement. but still it is inserting the values which are in b as well).
I am not sure if it is the problem with my if statement or with the cursor.
IF v_anwen2_id <> v_anwen_id
Below is my query.
SET serveroutput ON;
DECLARE
v_client_id NUMBER(38);
v_roles_id NUMBER(38);
v_old_roles NUMBER(38);
v_rights_id NUMBER(38);
v_user1_id NUMBER(38);
v_anwen_id NUMBER(38);
v_anwen2_id NUMBER(38);
v_client1_id NUMBER(38);
v_abtei NUMBER(38);
CURSOR c_abtei (var01 NUMBER) IS
SELECT abteil,client_id FROM ty_join_anwen_abteil WHERE anwen = var01;
CURSOR c_anwen (var02 NUMBER) IS
SELECT anwen FROM ty_join_anwen_abteil WHERE abteil = var02;
CURSOR c_roles (var03 NUMBER) IS
SELECT roles FROM ty_join_rolesn_righte WHERE right = var03;
CURSOR c_users (var04 NUMBER) IS
SELECT anwen FROM ty_join_anwen_rolesn WHERE roles = var04;
BEGIN
-- SELECT id INTO v_roles_id FROM ty_sd_roles WHERE description ='cod_Test';
SELECT id INTO v_rights_id FROM ty_sd_berightigung WHERE description ='failure_note';
-- INSERT INTO ty_join_rolesn_righte (role,right)
-- VALUES (v_roles_id,v_rights_id);
SELECT ID INTO v_user1_id FROM ty_sd_person WHERE email = 'jens#gmail.com';
OPEN c_abteil(v_user1_id);
LOOP
FETCH c_abteil INTO v_abteil,v_client1_id;
EXIT WHEN c_abteil%NOTFOUND;
OPEN c_anwen(v_abteil);
LOOP
FETCH c_anwen INTO v_anwen_id;
EXIT WHEN c_anwen%NOTFOUND;
-- INSERT INTO ty_join_anwen_rolesn (anwen,roles,client_id) VALUES (v_anwen_id,v_roles_id,v_client1_id);
END LOOP;
CLOSE c_anwen;
END LOOP;
CLOSE c_abteil;
OPEN c_roles(v_rights_id);
LOOP
FETCH c_roles INTO v_old_roles;
EXIT WHEN c_roles%NOTFOUND;
OPEN c_users(v_old_roles);
LOOP
FETCH c_users INTO v_anwen2_id;
EXIT WHEN c_users%NOTFOUND;
IF v_anwen2_id <> v_anwen_id
THEN
dbms_output.put_line(v_anwen2_id);
-- INSERT INTO ty_join_anwen_rolesn (anwen,roles,client_id) VALUES (v_anwen2_id,v_roles_id,v_client1_id);
END IF;
-- delete from ty_join_roles_right where roles = v_old_roles;
END LOOP;
CLOSE c_users;
END LOOP;
CLOSE c_roles;
END;
/

Answer 1

With due respect to your efforts, I dare to say It is not a good coding practice to open up these many cursors.
You can achieve this by joining all your tables in one SQL. Try to consolidate as much logic as possible in one or two SQLs.
Sample SQLs for your reference -
Select a.abteil, a.client_id, c.anwen
From ty_join_anwen_abteil a, ty_sd_person b, ty_join_anwen_abteil c
Where a.anwen = b.id
And b.email = 'jens#gmail.com'
And c.abteil. = a.abteil;
Select c.anwen
From ty_join_rolesn_righte a, ty_sd_berightigung b, ty_join_anwen_rolesn c
Where b.description ='failure_note'
And a.right = b.id
And c.roles = a.id