Sales details are being stored on a daily basis in the SALES_2007 table. A large amount of data is added to the table daily. To save disk space, you issued the following command:ALTER TABLE sales_2007 COMPRESS FOR ALL OPERATIONS;What would be the outcome of this command?()
A. It produces an error because data already exists in the table.
B. It produces an error because compression can be enabled at table creation only.
C. It compresses all data added or modified henceforth but the existing data in the table is not compressed immediately.
D. It immediately compresses all existing data as well as new data, resulting from either fresh additions or modifications to existing data.
第1题:
A.Thedirectorymustexistwithonesubdirectory(general).
B.Thedirectorymustexistwithtwosubdirectories(daily,weekly).
C.Thedirectorymustexistwiththreesubdirectories(daily,weekly,monthly).
D.Thedirectorymustexistwithfoursubdirectories(general,daily,weekly,monthly).
第2题:
Evaluate this SQL statement:e.employee_id, (.15* e.salary) + (.5 * e.commission_pct)+ (s.sales_amount * (.35 * e.bonus)) AS CALC_VALUEFROM employees e, sales sWHERE e.employee_id = s.emp_id;What will happen if you remove all the parentheses from the calculation?()
A.The value displayed in the CALC_VALUE column will be lower.
B.The value displayed in the CALC_VALUE column will be higher.
C.There will be no difference in the value displayed in the CALC_VALUE column.
D.An error will be reported.
第3题:
7、BookStore数据库中有销售明细表OrderDetail(OrderCode, BookCode, Amount) 查询销售总量前20%的图书,并按总销量降序排列。SQL语句: SELECT TOP 20 PERCENT Bookcode As 书号, SUM(Amount)As总销量 ROM OrderDetail GROUP BY Bookcode ORDER BY ________
A.Amount DESC
B.SUM(Amount) DESC
C.COUNT(Amount) DESC
D.ADD(Amount) DESC
第4题:
The operation of removing an element from the stack is said to( )the stack.
A. pop B. push C. store D. fetch
第5题:
第6题:
BookStore数据库中有销售明细表OrderDetail(OrderCode, BookCode, Amount) 查询销售总量前20%的图书,并按总销量降序排列。SQL语句: SELECT TOP 20 PERCENT Bookcode As 书号, SUM(Amount)As总销量 ROM OrderDetail GROUP BY Bookcode ORDER BY ________
A.Amount DESC
B.SUM(Amount) DESC
C.COUNT(Amount) DESC
D.ADD(Amount) DESC