Mega Code Archive

Use of EXECUTE IMMEDIATE for single-row queries

SQL> SQL> CREATE TABLE session ( 2 department CHAR(3), 3 course NUMBER(3), 4 description VARCHAR2(2000), 5 max_lecturer NUMBER(3), 6 current_lecturer NUMBER(3), 7 num_credits NUMBER(1), 8 room_id NUMBER(5) 9 ); Table created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('HIS', 101, 'History 101', 30, 11, 4, 20000); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('HIS', 301, 'History 301', 30, 0, 4, 20004); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('CS', 101, 'Computer Science 101', 50, 0, 4, 20001); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('ECN', 203, 'Economics 203', 15, 0, 3, 20002); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('CS', 102, 'Computer Science 102', 35, 3, 4, 20003); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('MUS', 410, 'Music 410', 5, 4, 3, 20005); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('ECN', 101, 'Economics 101', 50, 0, 4, 20007); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('NUT', 307, 'Nutrition 307', 20, 2, 4, 20008); 1 row created. SQL> SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id) 2 VALUES ('MUS', 100, 'Music 100', 100, 0, 3, NULL); 1 row created. SQL> DECLARE 2 v_SQLQuery VARCHAR2(200); 3 v_Class session%ROWTYPE; 4 v_Description session.description%TYPE; 5 BEGIN 6 v_SQLQuery := 7 'SELECT description ' || 8 ' FROM session ' || 9 ' WHERE department = ''ECN''' || 10 ' AND course = 203'; 11 12 EXECUTE IMMEDIATE v_SQLQuery 13 INTO v_Description; 14 15 DBMS_OUTPUT.PUT_LINE('Fetched ' || v_Description); 16 17 v_SQLQuery := 18 'SELECT * ' || 19 ' FROM session ' || 20 ' WHERE description = :description'; 21 EXECUTE IMMEDIATE v_SQLQuery 22 INTO v_Class 23 USING v_Description; 24 25 DBMS_OUTPUT.PUT_LINE( 26 'Fetched ' || v_Class.department || ' ' || v_Class.course); 27 28 v_SQLQuery := 'SELECT * FROM session'; 29 EXECUTE IMMEDIATE v_SQLQuery 30 INTO v_Class; 31 END; 32 / Fetched Economics 203 Fetched ECN 203 DECLARE * ERROR at line 1: ORA-01422: exact fetch returns more than requested number of rows ORA-06512: at line 29 SQL> SQL> drop table session; Table dropped. SQL>