对于以下SQL语句说法正确的是()SELECT ename FROM empWHERE sal IN (SELECT MAX(sal)FROM emp GROUP BY deptno); A. 这个语句是符合语法的B. 这个语句是不能执行的,因为缺少HAVING子句C. 这个语句是不能执行的,因为分组的条件列不在SELECT列表中D. 这个语句是不能执行的,因为GROUP BY子句应该在主查询中,而不是在子查询中E. 在主查询的WHERE条件中,不应该用IN,而应该用等号
对于以下SQL语句说法正确的是()SELECT ename FROM empWHERE sal IN (SELECT MAX(sal)FROM emp GROUP BY deptno);
A. 这个语句是符合语法的
B. 这个语句是不能执行的,因为缺少HAVING子句
C. 这个语句是不能执行的,因为分组的条件列不在SELECT列表中
D. 这个语句是不能执行的,因为GROUP BY子句应该在主查询中,而不是在子查询中
E. 在主查询的WHERE条件中,不应该用IN,而应该用等号
相关考题:
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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;
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
The EMP table has these columns: ENAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATE Management wants a list of names of employees who have been with the company for more than five years. Which SQL statement displays the required results?()A、SELECT ENAME FROM EMP WHERE SYSDATE-HIRE_DATE 5;B、SELECT ENAME FROM EMP WHERE HIRE_DATE-SYSDATE 5;C、SELECT ENAME FROM EMP WHERE (SYSDATE_HIRE_DATE)/365 5;D、SELECT ENAME FROM EMP WHERE (SYSDATE_HIRE_DATE)*/365 5;
单选题Evaluate this SQL statement: SELECT ename, sal, 12* sal+100 FROM emp; The SAL column stores the monthly salary of the employee. Which change must be made to the above syntax to calculate the annual compensation as "monthly salary plus a monthly bonus of $100, multiplied by 12"?()ANo change is required to achieve the desired results.BSELECT ename, sal, 12* (sal+100) FROM emp;CSELECT ename, sal, (12* sal)+100 FROM emp;DSELECT ename, sal +100,*12 FROM emp;
单选题对于以下SQL语句说法正确的是() SELECT ename FROM emp WHERE sal IN (SELECT MAX(sal) FROM emp GROUP BY deptno);A这个语句是符合语法的B这个语句是不能执行的,因为缺少HAVING子句C这个语句是不能执行的,因为分组的条件列不在SELECT列表中D这个语句是不能执行的,因为GROUP BY子句应该在主查询中,而不是在子查询中E在主查询的WHERE条件中,不应该用IN,而应该用等号
单选题A user executes a query on the EMP table, which contains thousands of rows, to get details about employees in one of the departments. The user receives the following error: SQL SELECT ename FROM emp WHERE deptno=10 ORDER BY sal; SELECT ename FROM emp WHERE deptno=10 ORDER BY sal * ERROR at line 1: ORA/x7f01157: cannot identify/lock data file 201 /x7f see DBWR trace file ORA/x7f01110: data file 201: ’/u01/app/oracle/oradata/orcl/temp01.dbf’ What is a possible reason?()AThe tempfile belonging to the default temporary tablespace is missing.BThe database is opened in restricted mode, so queries are not allowed.CThe default temporary tablespace required to execute the query is offline.DThe default temporary tablespace required to execute the query is dropped.EThe default temporary tablespace required to execute the query is readonly.
单选题A user executes a query on the EMPtable, which contains thousands of rows, to get details about employees in one of the departments. The user receives the following error: SQL SELECT ename FROM emp WHERE deptno=10 ORDER BY sal; SELECT ename FROM emp WHERE deptno=10 ORDER BY sal ERROR at line 1: ORA-01157: cannot identify/lock data file 201 - see DBWR trace file ORA-01110: data file 201:’/u01/app/oracle/oradata/orcl/temp01.dbf’ What is a possible reason?()A The tempfile belonging to the default temporary tablespace is missing.B The database is opened in restricted mode, so queries are not allowedC The default temporary tablespace required to execute the query is offline.D The default temporary tablespace required to execute the query is dropped.E The default temporary tablespace required to execute the query is read-only.
单选题执行如下两个查询,结果为() Select ename name,sal salary from emp order by salary Select ename name,sal“salary”from emp order by sal ascA两个查询结果完全相同B第一个查询正确,第二个查询错误C两个查询结构不同D第二个查询正确,第一个查询错误
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