检索公司员工中姓张的员工信息。显示字段：empno、ename、deptno。
检索公司员工中姓张的员工信息。显示字段：empno、ename、deptno。
相关考题：
以下语句不正确的是( )A.select * from emp;B.select ename,hiredate,sal from emp;C.select * from emp order deptno;D.select * from where deptno=1 and sal
在“值班信息”数据库中统计“员工信息”表中的“加班费”，并将结果写入“员工信息”表中的“加班费”字段。(2)建立视图shitu，包括“职工编码”，“姓名”和“夜值班天数”等字段，内容是夜值班天数在3天以上的员工。建立表单biao，在表单上显示视图shitu的内容。
在Oracle中,下面哪条语句当COMM字段为空时显示0,不为空时显示COMM的值()。 A.select ename,nvl（comm.,0）from empB.select ename,null（comm.,0）from empC.SELECT ename,NULLIF（comm,0）FROM empD.SELECT ename,DECODE（comm.,NULL,0）FROM emp
emp表有主键字段empno,现需要查询empno为100的ename,并赋值给变量v_ename,请写出PL／SQL块实现该功能,要求在PL／SQL块中能够捕捉到不存在记录的异常和其它未知异常,并显示出来。
MEDLINE光盘数据库的每一条记录大约是由26个字段组成的，其中又分为默认字 段和限制性字段两种，默认字段是指（）A检索时，用来默认显示的字段B不能进行字段限制检索的字段C如果不加限制，系统默认进行检索的字段D无论是否限制，系统都进行默认检索的字段
在Oracle中，下面哪条语句当COMM字段为空时显示0，不为空时显示COMM的值（）。A、select ename,nvl（comm.,0）from empB、select ename,null（comm.,0）from empC、SELECT ename,NULLIF（comm,0）FROM empD、SELECT ename,DECODE（comm.,NULL,0）FROM emp
《中国学术期刊全文数据库》中，在单逻辑检索的文摘字段中输入检索词“经济”检索的基础上，再在篇名字段中输入“全球化”，选“在结果中检索”再行检索。这个检索过程可以策略表示为（）。两次检索后，检索范围（）了。A、文摘字段：经济*篇名字段：全球化，扩大B、文摘字段：经济*篇名字段：全球化，缩小C、文摘字段：经济+篇名字段：全球化，扩大D、文摘字段：经济+篇名字段：全球化，缩小
语句SELECT * FROM dept WHERE NOT EXISTS （SELECT * FROM emp WHERE deptno=dept.deptno）执行后的结果为（）A、只显示存在于EMP表中的部门全部信息B、只显示不存在于EMP表中的部门全部信息C、未返回任何数据D、显示DEPT表中的全部信息
下面的查询中哪一个会产生笛卡尔集（）A、SELECT e.empno，e.ename， e.deptno， d.deptno，d.loc FROM emp e，dept d WHERE e.deptno=d.deptnoB、SELECT e.empno， e.ename， e.deptno， d.deptno，d.loc FROM emp e，dept dC、SELECT e.empno， e.ename， e.deptno， d.deptno，d.loc FROM emp e，dept d WHERE e.empno=101 and e.deptno=d.deptnoD、SELECT e.empno， e.ename， e.deptno， d.deptno，d.loc FROM emp e，dept d WHEREe.deptno=d.deptno and d.deptno=60
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')) );
A number of applications issue the following SQL statement:SELECT d.deptno, e.empno, e.salary FROM department d INNER JOIN employee e ON d.deptno = e.deptnoA database administrator wishes to store this query within the database. Which of the following database objects can be used to accomplish this?（）A、AliasB、ViewC、SchemaD、Trigger
Which SQL statement defines the FOREIGN KEY constraint on the DEPTNO column of the EMP table?（）A、CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) NOT NULL CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);B、CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));C、CREATE TABLE EMP (empno NUMBER(4) ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));D、CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp deptno fk REFERENCES dept (deptno));
User SCOTT executes the following command on the EMP table but has not issued COMMIT， ROLLBACK， or any data definition language （DDL） command： SQL SELECT ename FROM emp 2 WHERE job=’CLERK’ FOR UPDATE OF empno； SCOTT has opened another session to work with the database instance. Which three operations wouldwait when issued in SCOTT’s second session（）A、LOCK TABLE emp IN SHARE MODE；B、LOCK TABLE emp IN EXCLUSIVE MODE；C、UPDATE emp SET sal=sal*1.2 WHERE job=MANAGER；D、INSERT INTO emp（empno，ename） VALUES （1289，’Harry’）；E、SELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno；
Which SQL statement defines a FOREIGN KEY constraint on the DEPTNO column of the EMP table?（）A、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);B、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));C、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));D、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));
User SCOTT executes the following command on the EMP table but has not issued COMMIT， ROLLBACK， orany data definition language （DDL） command： SQL SELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno； SCOTT has opened another session to work with the database instance. Which three operations would waitwhen issued in SCOTT’s second session（）A、LOCK TABLE emp IN SHARE MODE；B、LOCK TABLE emp IN EXCLUSIVE MODE；C、UPDATE emp SET sal=sal*1.2 WHERE job=ANAGER？UPDATE emp SET sal=sal*1.2 WHERE job=？ANAGER？D、INSERT INTO emp（empno，ename） VALUES （1289，’Harry’）；E、SELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno
单选题The ADMIN_EMP table has columns EMPNO， ENAME， DEPTNO， and SAL. It has a materialized view EMP_MV with a materialized log and an ENAME_IDX index on the ENAME column. You need to perform an online table redefinition on the ADMIN_EMP table to move it from the TBS1 tablespace to the TBS2 tablespace in the same schema. What action is required for the dependent objects when you perform online redefinition on the table？（）A The materialized view should have a complete refresh performed after the online table redefinition is completed.B The materialized view should have a fast refresh performed after the online table redefinition is completed.C The materialized view，materialized log，and the index should be dropped and re-created after the online table redefinition is complete.D The materialized view and materialized log should be dropped and all constraints disabled and re-created after the online table redefinition is complete.
单选题EMPDET is an external table containing the columns EMPNO and ENAME. Which command would work in relation to the EMPDET table？ （）A AB BC CD D
单选题在信息检索技术中，算符AND、OR、NOT指的是哪一种信息检索技术方法（）。A截词检索B位置检索C布尔检索D字段检索