Execute Immediate and the in list

Question

Hello,
How do I format the in list when i am executing a query with execute immediate ?
I want to check if a character value is in ('5', '6', '7') ? Execute immediate treats my in list as a string instead of checking to see if the given value is in ny list of values or not. Please see the code / output below.
SQL> declare
2
3 v_result VARCHAR2 (1) := 'N';
4 v_num_list1 VARCHAR2 (40) := '''5''';
5 v_num_list2 VARCHAR2 (40) := '''5'',''6'',''7''';
6
7 v_in VARCHAR2 (100)
8 := 'BEGIN IF (:txn_value IN (:case_list)) THEN :result := ''Y''; END IF; END;';
9 v_ctrl_no varchar2(40) := '''5''';
10 BEGIN
11
12 DBMS_OUTPUT.PUT_LINE ('txn_value: ' || v_ctrl_no);
13 DBMS_OUTPUT.PUT_LINE ('case_list: ' || v_num_list1);
14
15 EXECUTE IMMEDIATE v_in
16 USING IN v_ctrl_no, v_num_list1, OUT v_result;
17
18 DBMS_OUTPUT.PUT_LINE ('result is ''' || v_result || '''');
19 v_result := 'N';
20
21 DBMS_OUTPUT.PUT_LINE ('txn_value: ' || v_ctrl_no);
22 DBMS_OUTPUT.PUT_LINE ('case_list: ' || v_num_list2);
23
24 EXECUTE IMMEDIATE v_in
25 USING IN v_ctrl_no, v_num_list2, OUT v_result;
26
27 DBMS_OUTPUT.PUT_LINE ('result is ''' || v_result || '''');
28
29 END;
30 /
txn_value: '5'
case_list: '5'
result is 'Y'
txn_value: '5'
case_list: '5','6','7'
result is 'N'
Thanks,
Anna

Answer 1

you can't use a bind variable for an in-list string.
you can rebuild the dynamic statement each time, without a bind variable:
sql := '... in ( ' || in_list_var ||' )...
or, you can use instr:
sql := ' ... instr(:in_list_var, :txn_val) > 0 ...'
using ','||in_list, ','||txn_val||','; -- notice the extra commas