Trigger Application Trigger

First, there is a table:

CREATE TABLE T_salary (  name   VARCHAR2, age number    (2),  SALARY number (5)), insert into t_salary (name, age, SALARY) VALUES (' Wyl ', Th, 63000), insert into t_salary (name, age, SALARY) VALUES (' Werxiao ', +, 6012); Insert I Nto t_salary (name, age, salary) VALUES (' Lisi ', si, 7000), insert into t_salary (name, age, salary) VALUES (' Zhangsan ', 42, 4521);

Trigger Scenario 1: Complex security checks, as follows

　　

CREATE OR REPLACE TRIGGER t_security_t_salarybefore updateon t_salary/*   trigger Scenario 1: Complex security checks   prohibit operating tables   during non-working hours Weekends or not between 9 and 18 points, for non-working time */begin  IF (To_char (sysdate, ' Day ') in (' Saturday ', ' Sunday ')) or  To_number (To_char (Sysdate, ' Hh24 ')) not between 9  and then--to_number (To_char (sysdate, ' hh24 ')) between 9 and then  --Prohibit insert new employee 
  
   raise_application_error ('-20002 ', ' non-working hours not allowed to operate this table ');  END IF; END;
  

Where the first parameter of Raise_application_error () is between 20999 and-20000. As follows:

Trigger Application Trigger