Updating a database

[hluash]

I want to save a record the I edited but I want to put the code under the save button and I have something like this:
DECLARE
l_rowid VARCHAR2(30);
CURSOR exists_cur
IS SELECT ROWID FROM tab_A
WHERE id = :tab_A .id;

BEGIN
IF :global.l_add = 't' THEN
COMMIT_FORM;
END IF;

IF :global.l_edit = 't' THEN
FETCH exists_cur INTO l_rowid;
IF exists_cur%FOUND THEN
UPDATE tab_a
SET field_1=:tab_A .field1, tab_A .SURNAME =:tab_A .SURNAME
WHERE ROWID = l_rowid;
ELSE
COMMIT_FORM;
END IF;
END IF;

CLEAR_FORM;
GO_FIELD('add_btn');

END;


Instead this just makes the my pc to hang can somebody tell me what makes it(pc) hang and how can save the updated info.

 

[sem]

Try to check whether the row you're trying to update is not locked by another session. Use select for update nowait in your cursor. This also prevents from changing/deleting already selected row by others.
BTW why do you select rowid explicitly instead of updating with 'where current of' clause? And I also can not see your open/close cursor statements.