会计电算化系统开发的全套文档资料，其保存期限截至该系统停止使用或有重大更改后的（)年。A．一年B．

e the SQL statement:SELECT *FROM ordersWHERE cust_id = (SELECT cust_idFROM customersWHERE cust_name = ‘Smith‘);What is the result when the query is executed？（）

A.A

B.B

C.C

D.D

E.E

e this SQL statement:SELECT cust_id, ord_totalFROM ordersWHERE ord_total > ANY(SELECT ord_totalFROM ordersWHERE cust_id IN (SELECT cust_idFROM customers WHERE city LIKE‘New York‘));What is the result when the above query is executed？（）

A.A

B.B

C.C

D.D

E.E

to display data. You build your Web Forms for the Web application by dragging and dropping tables from the Data Connections tree in Server Explorer. You need to add a connection to your data by using the Add Connection dialog box as shown in the exhibit. During the process, you need to configure the .NET Data Provider that you use to create the data source objects. What should you do？（）

A. Right-click the connection, and click Properties. Modify the Provider property of the data connection.

B. Click the Change button, and change the data provider for the selected data source.

C. Click the Advanced button, and change the Data Source property to the target provider.

D. Click the Advanced button, and change the Application Name property to the target provider.

SELECT last_nameFROM employeesWHERE salary IN (SELECT MAX(salary)FROM employeesGROUP BY department_id);Which statement is true？（）

A.The SELECT statement is syntactically accurate.

B.The SELECT statement does not work because there is no HAVING clause.

C.The SELECT statement does not work because the column specified in the GROUP BY clause is not in the SELECT list.

D.The SELECT statement does not work because the GROUP BY clause should be in the main query and not in the subquery.

e, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID column is a NOT NULL column.Evaluate this DELETE statement:DELETE employee_id, salary, job_idFROM employeesWHERE dept_id = 90;Why does the DELETE statement fail when you execute it？（）

A.There is no row with dept_id 90 in the EMPLOYEES table.

B.You cannot delete the JOB_ID column because it is a NOT NULL column.

C.You cannot specify column names in the DELETE clause of the DELETE statement.

D.You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.

A.SELECT employee_id, salary, tax_percent FROM employees e JOIN tax t ON e.salary BETWEEN t.min_salary AND t.max_salary;

B.SELECT employee_id, salary, tax_percent FROM employees e JOIN tax t WHERE e.salary > t.min_salary AND < t.max_salary;

C.SELECT employee_id, salary, tax_percent FROM employees e JOIN tax t ON (MIN(e.salary) = t.min_salary AND MAX(e.salary) = t.max_salary);

D.You cannot find the information because there is nocommon column between the two tables.

A．120M

B．320M

C．480M

D．600M

ws the monthly commission earned by the employee.Which three tasks would require subqueries or joins in order to be performed in a single step？（）

A.deleting the records of employees who do not earn commission

B.increasing the commission of employee 3 by the average commission earned in department 20

C.finding the number of employees who do NOT earn commission and are working for department 20

D.inserting into the table a new employee 10 who works for department 20 and earns a commission that is equal to the commission earned by employee 3

E.creating a table called COMMISSION that has the same structure and data as the columns EMP_ID and COMMISSION of the EMP table

F.decreasing the commission by 150 for the employees who are working in department 30 and earning a commission of more than 800

Whatever you do, you ______ click with the right mouse button or the program will crash.

A．must not

B．don't have to

C．doesn't have to

D．needn't