The EMP table contains these columns: LAST NAME VARCHAR2(25) SALARY NUMBER(6,2) DEPARTMENT_ID NUMBER(6) You need to display the employees who have not been assigned to any department. You write the SELECT statement: SELECT LAST_NAME, SALARY, DEPARTMENT_ID FROM EMP WHERE DEPARMENT_ID = NULL; What is true about this SQL statement? ()A、The SQL statement displays the desired results.B、The column in the WHERE clause should be changed to display the desired results.C、The operator in the WHERE clause should be changed to display the desired results.D、The WHERE clause should be changed to use an outer join to display the desired results.
The EMP table contains these columns: LAST NAME VARCHAR2(25) SALARY NUMBER(6,2) DEPARTMENT_ID NUMBER(6) You need to display the employees who have not been assigned to any department. You write the SELECT statement: SELECT LAST_NAME, SALARY, DEPARTMENT_ID FROM EMP WHERE DEPARMENT_ID = NULL; What is true about this SQL statement? ()
- A、The SQL statement displays the desired results.
- B、The column in the WHERE clause should be changed to display the desired results.
- C、The operator in the WHERE clause should be changed to display the desired results.
- D、The WHERE clause should be changed to use an outer join to display the desired results.
相关考题:
● 撤销 U5 对 Emp 表的查询权限,并收回 U5 授予其它用户的该权限,SQL 语句是 (51) 。(51)A. REVOKE SELECT ON TABLE Emp FROM U5 CASCADE;B. REVOKE SELECT ON TABLE Emp FROM U5 RESTRICT;C. REVOKE QUERY ON TABLE Emp FROM U5 CASCADE;D. GRANT SELECT ON TABLE Emp TO U5 WITH GRANT OPTION;
以下语句错误的是( )A. alter table emp delete column addcolumn;B. alter table emp modify column addcolumn char(10);C.alter table emp change addcolumn addcolumn int;D. alter table emp add column addcolumn int;
以下能够删除一列的是( )A.alter table emp remove addcolumnB.alter table emp drop column addcolumnC.alter table emp delete column addcolumnD.alter table emp delete addcolumn
You plan to use Flashback Drop feature to recover a dropped table SALES_EMP. No other table with the same name exists in the schema.You query RECYCLEBIN and find multiple entries for the SALES_EMP table as follows, You then issue the following statement to recover the table:SQL FLASHBACK TABLE sales_emp TO BEFORE DROP;What would be the outcome of the precedent statement?()A. It retrieves the latest version of the table from the recycle binB. It retrieves the oldest version of the table from the recycle binC. It retrieves the version of the table for which undo information is availableD. It returns an error because the table name is not specified as per the names in the OBJECT_NAME column
Which is a valid CREATE TABLE statement? () A. CREATE TABLE EMP9$# AS (empid number(2));B. CREATE TABLE EMP*123 AS (empid number(2));C. CREATE TABLE PACKAGE AS (packid number(2));D. CREATE TABLE 1EMP_TEST AS (empid number(2));
下列哪个操作可以将表中的数据删除,并且不需要回滚删除后回收其所占有的空间,但表定义保留() A.DELETE FROM EMP;B.TUNCATE TABLE EMP;C.TUNCATE TABLE EMP REUSE STORAGE;D.DROP TABLE EMP;E.以上所述都不正确
You are shrinking the SCOTT.EMP table by executing the ALTER TABLE SCOTT.EMP SHRINK SPACE CASCADE statement. What is a prerequisite for shrinking the SCOTT.EMP table?()A、 You must enable the block change tracking feature.B、 You must have enable the flashback feature.C、 You must use the OMF in your database.D、 You must define the tablespace of the SCOTT.EMP table for automatic segment space management.
下列哪个操作可以将表中的数据删除,并且不需要回滚删除后回收其所占有的空间,但表定义保留()A、DELETE FROM EMP;B、TUNCATE TABLE EMP;C、TUNCATE TABLE EMP REUSE STORAGE;D、DROP TABLE EMP;E、以上所述都不正确
Why would you use the following FLASHBACK TABLE command?() FLASHBACK TABLE emp TO TIMESTAMP (’11:45’,’hh12:mi’); A、to undo the changes made to the EMP table since the specified timeB、to restore the EMP table that was wrongly dropped from the databaseC、to view the transactions that have modified the EMP table since the specified timeD、to view the changes made to the EMP table for one or more rows since the specified timeE、to recover the EMP table to a point in time in the past by restoring the most recent backup
You executed the following FLASHBACK TABLE command: FLASHBACK TABLE emp TO TIMESTAMP (’11:45’,’hh12:mi’); Which two statements are correct? ()A、 The FLASHBACK TABLE statement will not be written to the alert log file.B、 The EMP table that was dropped by mistake from the database will be restored.C、 The changes made to the EMP table since the specified time will be undone.D、 The FLASHBACK TABLE statement will not maintain the existing indexes on the EMP table.E、 The FLASHBACK TABLE statement will be executed within a single transaction.F、 The list of transactions that have modified the EMP table since the specified time will be displayed.
单选题The EMP table contains these columns: EMPLOYEE_ID NUMBER(4) EMPNAME VARCHAR2 (25) SALARY NUMBER(9,2) HIRE_DATE DATE You query the database with this SQL statement: SELECT empname,hire_date HIREDATE, salary FROM EMP ORDER BY hire_date; How will the results be sorted?()ArandomlyBascending by dateCdescending by dateDascending alphabeticallyEdescending alphabetically
单选题View the Exhibit and examine the structure of the EMP table. You executed the following command to add a primary key to the EMP table: ALTER TABLE emp ADD CONSTRAINT emp_id_pk PRIMARY KEY (emp_id) USING INDEX emp_id_idx; Which statement is true regarding the effect of the command?()A The PRIMARY KEY is created along with a new index.B The PRIMARY KEY is created and it would use an existing unique index.C The PRIMARY KEY would be created in a disabled state because it is using an existing index.D The statement produces an error because the USING clause is permitted only in the CREATE TABLE command.
单选题下列哪个操作可以将表中的数据删除,并且不需要回滚删除后回收其所占有的空间,但表定义保留()ADELETE FROM EMP;BTUNCATE TABLE EMP;CTUNCATE TABLE EMP REUSE STORAGE;DDROP TABLE EMP;E以上所述都不正确
多选题In which two scenarios should you issue the following command?() FLASHBACK TABLE SCOTT.EMP TO TIMESTAMP SYSTIMESTAP- INTERVAL ’15’ MINUTE;Awhen the schema of the user, SCOTT, was deleted by mistake 15 minutes agoBwhen the table EMP of the SCOTT schema was dropped by mistake 15 minutes agoCwhen some rows of the table, EMP, in the SCOTT schema were deleted by mistake 15 minutes agoDwhen some incorrect values were inserted in the EMP table in the user Scott’s schema during the last 15 minutesEnever, because FLASHBACK TABLE is not a valid command in Oracle 10g.
单选题Why would you use the following FLASHBACK TABLE command?() FLASHBACK TABLE emp TO TIMESTAMP (’11:45’,’hh12:mi’);Ato undo the changes made to the EMP table since the specified timeBto restore the EMP table that was wrongly dropped from the databaseCto view the transactions that have modified the EMP table since the specified timeDto view the changes made to the EMP table for one or more rows since the specified timeEto recover the EMP table to a point in time in the past by restoring the most recent backup
单选题删除emp表的全部数据,但不提交,以下正确的语句是()ADELETE * FROM. EMPBDELETE FROM EMPCTRUNCATE TABLE EMPDDELETE TABLE EMP
单选题Why would you use the following FLASHBACK TABLE command?() FLASHBACK TABLE emp TO TIMESTAMP (’11:45’.’hh12:mi’);A to undo the changes made to the EMP table since the specified timeB to restore the EMP table that was wrongly dropped from the databaseC to view the transactions that have modified the EMP table since the specified timeD to view the changes made to the EMP table for one or more rows since the specified time
多选题You executed the following FLASHBACK TABLE command: FLASHBACK TABLE emp TO TIMESTAMP (’11:45’,’hh12:mi’); Which two statements are correct?()AThe FLASHBACK TABLE statement will not be written to the alert log file.BThe changes made to the EMP table since the specified time will be undone.CThe EMP table that was dropped by mistake from the database will be restored.DThe FLASHBACK TABLE statement will be executed within a single transaction.EThe FLASHBACK TABLE statement will not maintain the existing indexes on the EMP table.FThe list of transactions that have modified the EMP table since the specified time will be displayed.
单选题Which SQL statement defines a FOREIGN KEY constraint on the DEPTNO column of the EMP table?()ACREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);BCREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));CCREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));DCREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));
单选题You are performing the shrink operation on the SCOTT.EMP table. You want to perform the same operation on all dependent objects of the SCOTT.EMP table. What is NOT a prerequisite for the operation?()A You must enable the row movement on the SCOTT.EMP table.B You must define the tablespace of the SCOTT.EMP table for automatic segment space management.C You must use the CASCADE clause in the ALTER TABLE SHRINK SPACE statement.D You must use the COMPACT clause in the ALTER TABLE SHRINK SPACE statement.
单选题You are shrinking the SCOTT.EMP table by executing the ALTER TABLE SCOTT.EMP SHRINK SPACE CASCADE statement. What is a prerequisite for shrinking the SCOTT.EMP table?()A You must enable the block change tracking feature.B You must have enable the flashback feature.C You must use the OMF in your database.D You must define the tablespace of the SCOTT.EMP table for automatic segment space management.
单选题Which is a valid CREATE TABLE statement?()ACREATE TABLE EMP9$# AS (empid number(2));BCREATE TABLE EMP*123 AS (empid number(2));CCREATE TABLE PACKAGE AS (packid number(2));DCREATE TABLE 1EMP_TEST AS (empid number(2));
多选题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 job FROM emp 2 WHERE job=’CLERK’ FOR UPDATE OF empno; SCOTT has opened another session to work with the database. Which three operations would wait when issued in SCOTT’s second session?()ALOCK TABLE emp IN SHARE MODE;BLOCK TABLE emp IN EXCLUSIVE MODE;CDELETE FROM emp WHERE job=’MANAGER’;DINSERT INTO emp(empno,ename) VALUES (1289,’Dick’);ESELECT job FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno;
多选题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()ALOCK TABLE emp IN SHARE MODE;BLOCK TABLE emp IN EXCLUSIVE MODE;CUPDATE emp SET sal=sal*1.2 WHERE job=MANAGER;DINSERT INTO emp(empno,ename) VALUES (1289,’Harry’);ESELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno;
多选题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()ALOCK TABLE emp IN SHARE MODE;BLOCK TABLE emp IN EXCLUSIVE MODE;CUPDATE emp SET sal=sal*1.2 WHERE job=ANAGER?UPDATE emp SET sal=sal*1.2 WHERE job=?ANAGER?DINSERT INTO emp(empno,ename) VALUES (1289,’Harry’);ESELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno
单选题Which SQL statement defines the FOREIGN KEY constraint on the DEPTNO column of the EMP table?()ACREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) NOT NULL CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);BCREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));CCREATE TABLE EMP (empno NUMBER(4) ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));DCREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp deptno fk REFERENCES dept (deptno));
单选题Management has asked you to calculate the value 12*salary* commission_pct for all the employees in the EMP table. The EMP table contains these columns: LAST NAME VARCNAR2(35) NOT NULL SALARY NUMBER(9,2) NOT NULL COMMISION_PCT NUMBER(4,2) Which statement ensures that a value is displayed in the calculated columns for all employees?()ASELECT last_name, 12*salary* commission_pct FROM emp;BSELECT last_name, 12*salary* (commission_pct,0) FROM emp;CSELECT last_name, 12*salary*(nvl(commission_pct,0)) FROM emp;DSELECT last_name, 12*salary*(decode(commission_pct,0)) FROM emp;
单选题EXHIBIT, Emp Table Exhibit A Exhibit B Examine the data from the EMP table. Evaluate this SQL statement: SELECT * FROM emp WHERE emp _ id = 3); WHERE commission = (SELECT commission FROM emp What is the result when the query is executed?()A Exhibit AB Exhibit BC The query returns no rowsD The query fails because the outer query is retrieving more than one columnE The query fails because both the inner and outer queries are retrieving data from the same table.