Oracle PL/SQL capture lock exception in loop and continue - oracle

Question

I have a procedure below, which loops through a cursor does some logic. I have put FOR UPDATE NOWAIT on the cursor to lock my records set, in case someone from another session wants to update the same set.
But there may be a scenario where the records I have selected in my cursor, is locked by someone as well, in which case, I want to simply log the locked record in a log table and continue to the next record in the loop.
PROCEDURE test(p_id IN NUMBER)
IS
CURSOR cur_test IS
SELECT emp_id,
emp_name
FROM
EMP
FOR UPDATE NOWAIT;
row_locked EXCEPTION;
PRAGMA EXCEPTION_INIT(row_locked, -54);
BEGIN
FOR r_cur_test IN cur_test
LOOP
BEGIN
--do something
EXCEPTION
WHEN row_locked THEN
--log locked record in log table
log_lock('Record is locked');
COMMIT;
END;
END LOOP;
--call log function to log a successful run
COMMIT;
EXCEPTION
WHEN OTHERS THEN
--Unsuccessful completion of the run.Trap all unhandled exceptions.
--log error in error table
log_lock('Process exited with error');
ROLLBACK;
END;
for testing, I open session 1 and executed
select * from EMP FOR UPDATE NOWAIT
and in session 2, I executed
begin
test(1);
end;
it always went to the OTHERS exception, as a result of which, the procecure just terminated without continuing looping through the cursor.
Can anyone give me some advice? Thanks a lot

Answer 1

When you do open cursor for update this statement works in scenario: at first run select query and set lock for all records and after then do fetch operations.
PROCEDURE test(p_id IN NUMBER)
IS
CURSOR cur_test IS
SELECT emp_id,
emp_name,
rowid as row_id
FROM
EMP;
row_locked EXCEPTION;
PRAGMA EXCEPTION_INIT(row_locked, -54);
v_sql varchar2(4000) := 'SELECT 1 FROM EMP t WHERE rowid = :row_id FOR UPDATE NOWAIT';
c int;
n int;
BEGIN
c := dbms_sql.open_cursor;
dbms_sql.parse(c, v_sql, dbms_sql.native);
FOR r_cur_test IN cur_test
LOOP
BEGIN
dbms_sql.bind_variable (c, 'row_id', i.row_id);
n := dbms_sql.execute(c);
--do something
EXCEPTION
WHEN row_locked THEN
--log locked record in log table
log_lock('Record is locked');
COMMIT;
END;
END LOOP;
dbms_sql.close_cursor(c);
--call log function to log a successful run
COMMIT;
EXCEPTION
WHEN OTHERS THEN
--Unsuccessful completion of the run.Trap all unhandled exceptions.
--log error in error table
log_lock('Process exited with error');
dbms_sql.close_cursor(c);
ROLLBACK;
END;