网友您好, 请在下方输入框内输入要搜索的题目:

题目内容 (请给出正确答案)

The following statements:CREATE TABLE t1 (col1 INT NOT NULL, PRIMARY KEY(col1)); CREATE TABLE t2 (col1 INT NOT NULL, col2 CHAR(1) NOT NULL, PRIMARY KEY (col1, col2), FOREIGN KEY (col1) REFERENCES t1 (col1) ON DELETE CASCADE ON UPDATE RESTRICT); CREATE TABLE t3 (col1 INT NOT NULL, col2 INT NOT NULL, PRIMARY KEY (col1, col2),FOREIGN KEY (col1) REFERENCES t1 (col1) ON DELETE NO ACTION ON UPDATE RESTRICT);INSERT INTO t1 VALUES (1), (2); INSERT INTO t2 VALUES (1, ‘a‘), (1, ‘b‘), (2,‘c‘); INSERT INTO t3 VALUES (1, 100), (2, 200), (2,300);How many rows will be deleted by the following DELETE statement? DELETE FROM t1 WHERE col1= 1;()

A.4

B.3

C.1

D.0


参考答案

更多 “ The following statements:CREATE TABLE t1 (col1 INT NOT NULL, PRIMARY KEY(col1)); CREATE TABLE t2 (col1 INT NOT NULL, col2 CHAR(1) NOT NULL, PRIMARY KEY (col1, col2), FOREIGN KEY (col1) REFERENCES t1 (col1) ON DELETE CASCADE ON UPDATE RESTRICT); CREATE TABLE t3 (col1 INT NOT NULL, col2 INT NOT NULL, PRIMARY KEY (col1, col2),FOREIGN KEY (col1) REFERENCES t1 (col1) ON DELETE NO ACTION ON UPDATE RESTRICT);INSERT INTO t1 VALUES (1), (2); INSERT INTO t2 VALUES (1, ‘a‘), (1, ‘b‘), (2,‘c‘); INSERT INTO t3 VALUES (1, 100), (2, 200), (2,300);How many rows will be deleted by the following DELETE statement? DELETE FROM t1 WHERE col1= 1;()A.4B.3C.1D.0 ” 相关考题
考题 在文件系统中,若要实现文件拷贝功能,可利用已有的系统调用,它们是A.create,open,read,write,closeB.create,open,read,write,deleteC.create,open,read,writeD.create,read,write,close

考题 Yourapplicationrequiresthatyouprogrammaticallymanipulateanonqueryrecordgroup.Whichthreebuilt-inscanyouuse?() A.CREATE_GROUPB.ADD_GROUP_NOWC.POPULATE_GROUPD.ADD_GROUP_COLUMNE.CREATE_GROUP_FROM_QUERY

考题 YouworkwithadatabasenamedDB1,whichislocatedonaSQLServer2005computer.YoudiscoverthatatablescanonTable1inDB1causesaslowquery.Table1isaverylargetablethatisusedfrequently.Youascertainthatthequerycontainsthefollowingstatement.SELECTcol1,col2FROMtable1WHEREcol3=Youneedtoprovidemaximumqueryperformance.Table1mustremainavailabletousers.Whatshouldyoudo?()A.UpdateallstatisticsonTable1inDB1.B.UsetheCREATESTATISTICSstatementinDB1tocreatemissingstatisticsoncol3ofTable1.C.Setthepriorityboostserveroptionto1.D.Executethefollowingstatement.USEDB1GOCREATEINDEXindex1ONtable1(col3)INCLUDE(col1,col2)WITH(ONLINE=ON)GO

考题 下列四组SQL命令,全部属于数据定义语句的命令是()A.CREATE,DROP,UPDATEB.CREATE,DROP,ALTERC.CREATE,DROP,GRANTD.CREATE,DROP,SELECT

考题 下列哪组SQL命令全部属于数据定义语句的命令?()A.CREATE,DROP,ALTERB.CREATE,DROP,SELECTC.CREATE,DROP,GRANTD.CREATE,DROP,UPDATE

考题 对于表A(col1 int,col2 char(1))使用聚合函数sum,下面语句正确的是()A.select sum(col2) as col2 from A group by col1B.select sum(col1) as col1 from A group by col2C.select sum(col1) as col1,col2 from A group by col1D.select sum(col2) as col1 from A group by col2

考题 【单选题】对于建立在数据库上的DDL触发器,常用的激活DDL触发器的事件不包括()A.Create_Table,Alter_Table,Drop_TableB.Create_View,Alter_View,Drop_ViewC.Create_Procedure,Alter_Procedure,Drop_ProcedureD.Rollback

考题 下列四组SQL命令,全部属于数据定义语句的命令是()。A.CREATE,DROP,ALTERB.CREATE,DROP,UPDATEC.CREATE,DROP,GRANTD.CREATE,DROP,SELECT

考题 如果要让某个用户能够在所有模式下建表应该授予此用户哪个权限?A.create tableB.create any tableC.create all tableD.create * table