A.select ename,job,sal from emp where sal in(select avg(sal) from emp group by deptno)
B.select ename,job,sal from emp where sal in(select min(sal) from emp order by deptno)
C.select ename,job,sal from emp where sal in(select min(sal) from emp group by deptno)
D.select ename,job,min(sal) from emp where sal group by deptno
A.job;work
B.work;job
C.job;job
D.work;work
A.select deptno, max(salary) from emp group by deptn
B.select job, max(salary) from emp group by job having max(salary)>10000
C.select job, max(salary) from emp order by job
D.select job, max(salary) from emp group by salary having max(salary)>10000
Apache Spark是专为大规模数据处理而设计的快速通用的计算引擎,将Job中间输出结果可以保存在()中,从而不再需要读写HDFS。因此Spark能更好地适用于数据挖掘与机器学习等需要迭代的Map Reduce的算法。