SQL语句调试与优化考题及答案.docx
SQL语句调试与优化考题及答案
姓名:____________________
一、单项选择题(每题2分,共10题)
1.以下哪个SQL语句可以查询名为“students”的表中年龄大于20的所有学生的姓名?
A.SELECTnameFROMstudentsWHEREage20
B.SELECTnameFROMstudentsWHEREage=20
C.SELECTnameFROMstudentsWHEREage=20
D.SELECTnameFROMstudentsWHEREage20
2.在SQL中,如何删除名为“products”的表中所有记录?
A.DELETEFROMproducts
B.DROPTABLEproducts
C.TRUNCATETABLEproducts
D.ALTERTABLEproductsDROP
3.以下哪个SQL语句可以创建一个名为“orders”的表,包含字段“order_id”和“customer_id”?
A.CREATETABLEorders(order_idINT,customer_idINT)
B.CREATETABLEorders(order_idINT,customer_idINT)ENGINE=InnoDB
C.CREATETABLEorders(order_idINT,customer_idINT)TYPE=InnoDB
D.CREATETABLEorders(order_idINT,customer_idINT)CHARACTERSET=utf8
4.在SQL中,如何将名为“users”的表中所有记录的年龄字段值增加1?
A.UPDATEusersSETage=age+1
B.UPDATEusersSETage+=1
C.UPDATEusersSETage=age-1
D.UPDATEusersSETage-=1
5.以下哪个SQL语句可以查询名为“employees”的表中所有部门为“sales”的员工姓名和职位?
A.SELECTname,positionFROMemployeesWHEREdepartment=sales
B.SELECTname,positionFROMemployeesWHEREdepartment=salesANDposition=manager
C.SELECTname,positionFROMemployeesWHEREdepartment=salesORposition=manager
D.SELECTname,positionFROMemployeesWHEREdepartment=salesANDposition!=manager
6.在SQL中,如何将名为“orders”的表中所有订单状态为“shipped”的订单号更新为“delivered”?
A.UPDATEordersSETorder_id=deliveredWHEREstatus=shipped
B.UPDATEordersSETorder_id=deliveredWHEREstatus=shippedANDorder_idISNOTNULL
C.UPDATEordersSETorder_id=deliveredWHEREstatus=shippedANDorder_id=delivered
D.UPDATEordersSETorder_id=deliveredWHEREstatus=shippedORorder_id=delivered
7.以下哪个SQL语句可以查询名为“products”的表中价格在10到20元之间的所有产品名称?
A.SELECTnameFROMproductsWHEREpriceBETWEEN10AND20
B.SELECTnameFROMproductsWHEREprice=10ANDprice=20
C.SELECTnameFROMproductsWHEREprice10ANDprice20
D.SELECTnameFROMproductsWHEREpriceBETWEEN10AND20ORpriceBETWEEN20AND1