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单选题
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
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更多 “单选题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
若某企业的数据库系统中有如下所示的员工关系和仓库关系，每个仓库可有多名员工，但只有一名负责人。员工关系(cmployee)：仓库关系(warehouse)：则创建仓库表结构的SQL语句为(58)。A．CREATE TABLE(employeeID CHAR(2)NOT NULL UNIQUE, name CHAR(30)NOT NULL, address CHAR(40), pricipallD CHAR(3));B．CREATE warehouse(warehouseD CHAR(2)PRIMARY KEY, name CHAR(30), address CHAR(40), pficipalID CHAR(3));C．CREATE TABLE warehouse(warehouselD CHAR(2)PRIMARY KEY, name CHAR(30)NOT NULL, address CHAR(40), pricipalID CHAR(3), FOREIGN KEY(priciPalID)REFERENCES employee(employeeID));D．CREATE TABLE warehouse(warehouselD CHAR(2), name CHAR(30)NOT NULL, address CHAR(40), pricipalID CHAR(3), PRIMARY KEY(warehouselD), FOREIGN KEY(employeeID)REFERENCES emplo
考题
Given the following requirements:Create a table to contain employee data, with a unique numeric identifier automatically assigned when a row is added, has an EDLEVEL column that permits only the values ‘C‘, ‘H‘ and ‘N‘, and permits inserts only when a corresponding value for the employee‘s department exists in the DEPARTMENT table.Which of the following CREATE statements will successfully create this table?（）A.CREATE TABLE emp ( empno SMALLINT NEXTVAL GENERATED ALWAYS AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3) NOT NULL, edlevel CHAR(1), PRIMARY KEY emp_pk (empno), FOREIGN KEY emp_workdept_fk ON (workdept) REFERENCES department (deptno), CHECK edlevel_ck VALUES (edlevel IN (‘C‘,‘H‘,‘N‘)), );B.CREATE TABLE emp ( empno SMALLINT NOT NULL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3), edlevel CHAR(1), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY (workdept) REFERENCES department (deptno), CONSTRAINT edlevel_ck CHECK edlevel VALUES (‘C‘,‘H‘,‘N‘) );C.CREATE TABLE emp ( empno SMALLINT NEXTVAL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3) NOT NULL, edlevel CHAR(1) CHECK IN (‘C‘,‘H‘,‘N‘)), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY department (deptno) REFERENCES (workdept) );D.CREATE TABLE emp ( empno SMALLINT NOT NULL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3), edlevel CHAR(1), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY (workdept) REFERENCES department (deptno), CONSTRAINT edlevel_ck CHECK (edlevel IN (‘C‘,‘H‘,‘N‘)) );
考题
Given the following DDL and INSERT statements:CREATE VIEW v1 AS SELECT col1 FROM t1 WHERE col1 10; CREATE VIEW v2 AS SELECT col1 FROM v1 WITH CASCADED CHECK OPTION; CREATE VIEW v3 AS SELECT col1 FROM v2 WHERE col1 100; INSERT INTO v1 VALUES(5); INSERT INTO v2 VALUES(5); INSERT INTO v3 VALUES(20); INSERT INTO v3 VALUES(100);How many of these INSERT statements will be successful?（）A.0B.1C.2D.3
考题
Given the following statements:CREATE TABLE tab1 (col1 INT); CREATE TABLE tab2 (col1 INT); CREATE TRIGGER trig1 AFTER UPDATE ON tab1 REFERENCING NEW AS new1 FOR EACH ROW MODE DB2SQL INSERT INTO tab2 VALUES(new1.col1); INSERT INTO tab1 VALUES(2),(3);What is the result of the following query? SELECT count(*) FROM tab2;（）A.3B.2C.1D.0
考题
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
考题
某企业的数据库系统中有如下所示的员工关系和仓库关系，每个仓库可有多名员工，但只有一名负责人。员工关系(employee)：仓库关系(warehouse)：则创建仓库表结构的SQL语句为(58)。A．CREATE TABLE (employee ID CHAR(2)NOTNULL UNIQUE， name CHAR(30)NOT NULL， address CHAR(40)， principal ID CHAR(3))；B．CREATE warehouse(warehouse ID CHAR(2)PRIMARY KEY， name CHAR(30)， address CHAR(40)， principal ID CHAR(3))；C．CREATE TABLE warehouse(warehouse ID CHAR(2)PRIMARY KEY， name CHAR(30)NOT NULL， address CHAR(40)， principal ID CHAR(3)， FOREIGN KEY(principal ID)REFERENCES employee(employee ID))；D．CREATE TABIE warehouse(warehouse ID CHAR(2)， name CHAR(30)NOT NULL， address CHAR(40)， principal ID CHAR(3)， PRIMARY REY(warehouse ID)， FOREIGN KEY(employee ID)REFERENCES employee(employee ID))；
考题
Given the following DDL and INSERT statements: CREATE VIEW v1 AS SELECT col1 FROM t1 WHERE col1 10; CREATE VIEW v2 AS SELECT col1 FROM v1 WITH CASCADED CHECK OPTION; CREATE VIEW v3 AS SELECT col1 FROM v2 WHERE col1 100; INSERT INTO v1 VALUES(5); INSERT INTO v2 VALUES(5); INSERT INTO v3 VALUES(20); INSERT INTO v3 VALUES(100); How many of these INSERT statements will be successful?（）A、0B、1C、2D、3
考题
If a unique constraint is defined on column COL1 of table TAB1, what are the characteristics of COL1?（）A、COL1 will accept NULL values and can be referenced in another table's foreign key specification.B、COL1 will not accept NULL values and cannot be referenced in another tables foreign key specification.C、COL1 will not accept NULL values and can be referenced in another tables foreign key specification.D、COL1 will accept NULL values and cannot be referenced in another tables foreign key specification.
考题
对于表A（col1 int，col2 char（1）），表B（col1 int，col2char（1）），为确保表A的数据全部被保留，下面正确的联接方式是（）A、A inner join BB、A left join BC、A right join BD、Across join B
考题
对于表A（col1 int，col2 char（1））更新col1=1的数据col2值为N，下面语句正确的是（）A、update table A setcol2=’N’ where col1=1B、modify table A setcol2=N where col1=1C、update A set col2=’N’ where col1=1D、modify A set col2=N where col1=1
考题
存在两个结构相同的数据库表T1（col1，col2，col3）、T2（col1，col2，col3），写出一SQL语句将所有T1数据导入到T2表（）A、select col1，col2，col3 from T1 into T2（col1，col2，col3）B、insert T1 （col1，col，col3） into T2（col1，col2，col3）C、insert into T2 （col1，col2，col3） as select col1，col2，col3 from T1D、insert into T2（col1，col2，col3） select col1，col2，col3 from T1；
考题
Given the following statements: CREATE TABLE tab1 (col1 INT); CREATE TABLE tab2 (col1 INT); CREATE TRIGGER trig1 AFTER UPDATE ON tab1 REFERENCING NEW AS new1 FOR EACH ROW MODE DB2SQL INSERT INTO tab2 VALUES(new1.col1); INSERT INTO tab1 VALUES(2),(3); What is the result of the following query? SELECT count(*) FROM tab2;（）A、3B、2C、1D、0
考题
Given the following requirements: Create a table to contain employee data, with a unique numeric identifier automatically assigned when a row is added, has an EDLEVEL column that permits only the values 'C', 'H' and 'N', and permits inserts only when a corresponding value for the employee's department exists in the DEPARTMENT table. Which of the following CREATE statements will successfully create this table?（）A、CREATE TABLE emp ( empno SMALLINT NEXTVAL GENERATED ALWAYS AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3) NOT NULL, edlevel CHAR(1), PRIMARY KEY emp_pk (empno), FOREIGN KEY emp_workdept_fk ON (workdept) REFERENCES department (deptno), CHECK edlevel_ck VALUES (edlevel IN ('C','H','N')), );B、CREATE TABLE emp ( empno SMALLINT NOT NULL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3), edlevel CHAR(1), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY (workdept) REFERENCES department (deptno), CONSTRAINT edlevel_ck CHECK edlevel VALUES ('C','H','N') );C、CREATE TABLE emp ( empno SMALLINT NEXTVAL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3) NOT NULL, edlevel CHAR(1) CHECK IN ('C','H','N')), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY department (deptno) REFERENCES (workdept) );D、CREATE TABLE emp ( empno SMALLINT NOT NULL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3), edlevel CHAR(1), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY (workdept) REFERENCES department (deptno), CONSTRAINT edlevel_ck CHECK (edlevel IN ('C','H','N')) );
考题
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
考题
Given two collection objects referenced by col1 and col2，which of these statements are true？（）A、The operation col1.retainAll（col2） will not modify the col1 object.B、The operation col1.removeAll（col2） will not modify the col2 object.C、The operation col1.addAll（col2） will return a new collection object， containing elements from both col1 and col2.D、The operation col1.containsAll（Col2） will not modify the col1 object.
考题
Which two statements are true about constraints? （）A、The UNIQUE constraint does not permit a null value for the column.B、A UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.C、The PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.D、The NOT NULL constraint ensures that null values are not permitted for the column.
考题
You work with a database named DB1， which is located on a SQL Server 2005 computer. You discover that a table scan on Table1 in DB1 causes a slow query. Table1 is a very large table that is used frequently. You ascertain that the query contains the following statement. SELECT col1， col2 FROM table1 WHERE col3 = You need to provide maximum query performance. Table1 must remain available to users. What should you do？（）A、Update all statistics on Table1 in DB1.B、Use the CREATE STATISTICS statement in DB1 to create missing statistics on col3of Table1.C、Set the priority boost server option to 1.D、Execute the following statement.USE DB1GOCREATE INDEX index1 ON table1（col3）INCLUDE（col1， col2） WITH （ONLINE = ON）GO
考题
单选题对于表A（col1 int，col2 char（1）），表B（col1 int，col2char（1）），为确保表A的数据全部被保留，下面正确的联接方式是（）A
A inner join BB
A left join BC
A right join BD
Across join B
考题
单选题You work with a database named DB1， which is located on a SQL Server 2005 computer. You discover that a table scan on Table1 in DB1 causes a slow query. Table1 is a very large table that is used frequently. You ascertain that the query contains the following statement. SELECT col1， col2 FROM table1 WHERE col3 = You need to provide maximum query performance. Table1 must remain available to users. What should you do？（）A
Update all statistics on Table1 in DB1.B
Use the CREATE STATISTICS statement in DB1 to create missing statistics on col3of Table1.C
Set the priority boost server option to 1.D
Execute the following statement.USE DB1GOCREATE INDEX index1 ON table1（col3）INCLUDE（col1， col2） WITH （ONLINE = ON）GO
考题
单选题Given the following DDL and INSERT statements: CREATE VIEW v1 AS SELECT col1 FROM t1 WHERE col1 10; CREATE VIEW v2 AS SELECT col1 FROM v1 WITH CASCADED CHECK OPTION; CREATE VIEW v3 AS SELECT col1 FROM v2 WHERE col1 100; INSERT INTO v1 VALUES(5); INSERT INTO v2 VALUES(5); INSERT INTO v3 VALUES(20); INSERT INTO v3 VALUES(100); How many of these INSERT statements will be successful?（）A
0B
1C
2D
3
考题
单选题存在两个结构相同的数据库表T1（col1，col2，col3）、T2（col1，col2，col3），写出一SQL语句将所有T1数据导入到T2表（）A
select col1，col2，col3 from T1 into T2（col1，col2，col3）B
insert T1 （col1，col，col3） into T2（col1，col2，col3）C
insert into T2 （col1，col2，col3） as select col1，col2，col3 from T1D
insert into T2（col1，col2，col3） select col1，col2，col3 from T1；
考题
单选题对于表A（col1 int，col2 char（1））更新col1=1的数据col2值为N，下面语句正确的是（）A
update table A setcol2=’N’ where col1=1B
modify table A setcol2=N where col1=1C
update A set col2=’N’ where col1=1D
modify A set col2=N where col1=1
考题
多选题Which two statements are true about constraints? （）AThe UNIQUE constraint does not permit a null value for the column.BA UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.CThe PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.DThe NOT NULL constraint ensures that null values are not permitted for the column.
考题
单选题Given the following statements: CREATE TABLE tab1 (col1 INT); CREATE TABLE tab2 (col1 INT); CREATE TRIGGER trig1 AFTER UPDATE ON tab1 REFERENCING NEW AS new1 FOR EACH ROW MODE DB2SQL INSERT INTO tab2 VALUES(new1.col1); INSERT INTO tab1 VALUES(2),(3); What is the result of the following query? SELECT count(*) FROM tab2;（）A
3B
2C
1D
0
考题
单选题Given the following requirements: Create a table to contain employee data, with a unique numeric identifier automatically assigned when a row is added, has an EDLEVEL column that permits only the values 'C', 'H' and 'N', and permits inserts only when a corresponding value for the employee's department exists in the DEPARTMENT table. Which of the following CREATE statements will successfully create this table?（）A
CREATE TABLE emp ( empno SMALLINT NEXTVAL GENERATED ALWAYS AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3) NOT NULL, edlevel CHAR(1), PRIMARY KEY emp_pk (empno), FOREIGN KEY emp_workdept_fk ON (workdept) REFERENCES department (deptno), CHECK edlevel_ck VALUES (edlevel IN ('C','H','N')), );B
CREATE TABLE emp ( empno SMALLINT NOT NULL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3), edlevel CHAR(1), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY (workdept) REFERENCES department (deptno), CONSTRAINT edlevel_ck CHECK edlevel VALUES ('C','H','N') );C
CREATE TABLE emp ( empno SMALLINT NEXTVAL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3) NOT NULL, edlevel CHAR(1) CHECK IN ('C','H','N')), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY department (deptno) REFERENCES (workdept) );D
CREATE TABLE emp ( empno SMALLINT NOT NULL GENERATED BY DEFAULT AS IDENTITY, firstname VARCHAR(30) NOT NULL, lastname VARCHAR(30) NOT NULL, workdept CHAR(3), edlevel CHAR(1), CONSTRAINT emp_pk PRIMARY KEY (empno), CONSTRAINT emp_workdept_fk FOREIGN KEY (workdept) REFERENCES department (deptno), CONSTRAINT edlevel_ck CHECK (edlevel IN ('C','H','N')) );
考题
多选题Given two collection objects referenced by col1 and col2，which of these statements are true？（）AThe operation col1.retainAll（col2） will not modify the col1 object.BThe operation col1.removeAll（col2） will not modify the col2 object.CThe operation col1.addAll（col2） will return a new collection object， containing elements from both col1 and col2.DThe operation col1.containsAll（Col2） will not modify the col1 object.
考题
单选题If a unique constraint is defined on column COL1 of table TAB1, what are the characteristics of COL1?（）A
COL1 will accept NULL values and can be referenced in another table's foreign key specification.B
COL1 will not accept NULL values and cannot be referenced in another tables foreign key specification.C
COL1 will not accept NULL values and can be referenced in another tables foreign key specification.D
COL1 will accept NULL values and cannot be referenced in another tables foreign key specification.
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