Index not getting created using stored procedure - Oracle - oracle

Question

I have this stored procedure to create index on table:
CREATE OR REPLACE PROCEDURE create_index (
in_tb VARCHAR2,
in_index VARCHAR2,
in_columns VARCHAR2,
lc_status OUT NUMBER
) AS
lc_affected NUMBER;
lc_stmt VARCHAR2(1500);
BEGIN
lc_stmt := 'BEGIN EXECUTE IMMEDIATE ''CREATE INDEX '
|| in_index
|| ' ON '
|| in_tb
|| ' ('
|| in_columns
|| ')''; END;';
dbms_output.put_line(lc_stmt);
dbms_utility.exec_ddl_statement(lc_stmt);
lc_affected := SQL%rowcount;
dbms_output.put_line('AFFECTED -->' || lc_affected);
IF ( lc_affected > 0 ) THEN
lc_status := 1;
ELSE
lc_status := 1;
END IF;
END create_index;
/
I execute the stored procedure using:
SET SERVEROUTPUT ON;
DECLARE
lc_status NUMBER;
BEGIN
create_index('TABLE_1_LOAD', 'ON_RUN_INDEX', 'MY_ID', lc_status);
END;
However, the index is not getting created in table TABLE_1_LOAD.
The output is:
BEGIN EXECUTE IMMEDIATE 'CREATE INDEX ON_RUN_INDEX ON TABLE_1_LOAD (MY_ID)'; END;
AFFECTED -->
PL/SQL procedure successfully completed.
I am not able to understand why the stored procedure is not creating indexes. Can you please help?

Answer 1

The dynamic statement you are trying to run via exec_ddl_statement is not DDL. It contains DDL, but embedded in an anonymous PL/SQL block, which is not the same thing. It looks like the dbms_utility procedure is just silently ignoring it for that reason.
If you simplify your statement to remove the unnecessary block then it will work:
...
BEGIN
lc_stmt := 'CREATE INDEX '
|| in_index
|| ' ON '
|| in_tb
|| ' ('
|| in_columns
|| ')';
...
Demo:
create table table_1_load (my_id number);
Table TABLE_1_LOAD created.
CREATE OR REPLACE PROCEDURE create_index (
in_tb VARCHAR2,
in_index VARCHAR2,
in_columns VARCHAR2,
lc_status OUT NUMBER
) AS
lc_affected NUMBER;
lc_stmt VARCHAR2(1500);
BEGIN
lc_stmt := 'CREATE INDEX '
|| in_index
|| ' ON '
|| in_tb
|| ' ('
|| in_columns
|| ')';
dbms_output.put_line(lc_stmt);
dbms_utility.exec_ddl_statement(lc_stmt);
lc_affected := SQL%rowcount;
dbms_output.put_line('AFFECTED -->' || lc_affected);
IF ( lc_affected > 0 ) THEN
lc_status := 1;
ELSE
lc_status := 1;
END IF;
END create_index;
/
Procedure CREATE_INDEX compiled
SET SERVEROUTPUT ON;
DECLARE
lc_status NUMBER;
BEGIN
create_index('TABLE_1_LOAD', 'ON_RUN_INDEX', 'MY_ID', lc_status);
END;
/
CREATE INDEX ON_RUN_INDEX ON TABLE_1_LOAD (MY_ID)
AFFECTED -->
PL/SQL procedure successfully completed.
The 'affected' number is still null, because execute_ddl_statement doesn't cause SQL%rowcount to be set, so you can't rely on that to tell you anything. But the index has been created:
select object_type, object_name from user_objects where created > trunc(sysdate);
OBJECT_TYPE OBJECT_NAME
------------------- ------------------------------
TABLE TABLE_1_LOAD
PROCEDURE CREATE_INDEX
INDEX ON_RUN_INDEX
You could run your original statement with execute immediate, and that would actually set SQL%rowcount, but as you still haven't run any DML it's meaningless really. To show that, with the (still unnecessary) anonymous block you get 1; without the block, using the same simplified statement as above, you get 0.