我需要一個觸發器來檢查超額會費。觸發檢查會費
如果它已經結束,它應該從一個名爲loan的表中將一些細節放到一個名爲fine的表中,但是,我創建的觸發器會給出編譯錯誤。
SQL> CREATE OR REPLACE TRIGGER Over_Due
2 AFTER INSERT OR UPDATE ON loan_table
3 FOR EACH ROW
4 DECLARE due_date DATE;
5 BEGIN
6 SELECT COUNT(*) INTO due_date FROM loan_table l
7 WHERE l.date_due = :new.date_due;
8 IF(date_due > SYSDATE)
9 THEN
10 INSERT INTO fine_table VALUES(fine_id, :old.loan_id,:old.book_id,:old.student_id,amount);
11 END IF;
END; 12
13/
Warning: Trigger created with compilation errors.
SQL> show errors;
Errors for TRIGGER OVER_DUE:
LINE/COL ERROR
-------- -----------------------------------------------------------------
3/1 PL/SQL: SQL Statement ignored
3/8 PL/SQL: ORA-00932: inconsistent datatypes: expected DATE got
NUMBER