Sure, here are the SQL commands to create the triggers you asked for: (a) To create a trigger that verifies that the updated salary of an employee must be greater than his/her previous salary, you can use the following SQL command: ```sql CREATE TRIGGER check_salary_increase BEFORE UPDATE ON employees FOR EACH ROW BEGIN IF NEW.salary = 5 THEN SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'Error: Number of employees in department 2 should not exceed 5.'; END IF; END; ``` This trigger is activated before an insert on the `employees` table. It checks if the new employee is being assigned to department 2 (`NEW.department_id = 2`) and if the number of employees in department 2 is already 5 or more. If both conditions are true, it raises an error. Please note that these triggers are written in MySQL syntax and the `SIGNAL` statement is used to raise an error. The exact syntax might vary depending on your SQL database system.

Question

Sure, here are the SQL commands to create the triggers you asked for:

(a) To create a trigger that verifies that the updated salary of an employee must be greater than his/her previous salary, you can use the following SQL command:

```sql
CREATE TRIGGER check_salary_increase
BEFORE UPDATE ON employees
FOR EACH ROW
BEGIN
   IF NEW.salary <= OLD.salary THEN
      SIGNAL SQLSTATE '45000'
         SET MESSAGE_TEXT = 'Error: Updated salary must be greater than the previous salary.';
   END IF;
END;
```

This trigger is activated before an update on the `employees` table. It compares the new salary (`NEW.salary`) with the old salary (`OLD.salary`). If the new salary is less than or equal to the old salary, it raises an error.

(b) To create a trigger that verifies that for the department 2, the number of employees should not exceed 5, you can use the following SQL command:

```sql
CREATE TRIGGER check_dept2_employee_count
BEFORE INSERT ON employees
FOR EACH ROW
BEGIN
   IF NEW.department_id = 2 AND 
      (SELECT COUNT(*) FROM employees WHERE department_id = 2) >= 5 THEN
      SIGNAL SQLSTATE '45000'
         SET MESSAGE_TEXT = 'Error: Number of employees in department 2 should not exceed 5.';
   END IF;
END;
```

This trigger is activated before an insert on the `employees` table. It checks if the new employee is being assigned to department 2 (`NEW.department_id = 2`) and if the number of employees in department 2 is already 5 or more. If both conditions are true, it raises an error.

Please note that these triggers are written in MySQL syntax and the `SIGNAL` statement is used to raise an error. The exact syntax might vary depending on your SQL database system.

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