一、运行一下算圆周率的测试代码,看下报错
cd /home/data_warehouse/module/hadoop-3.1.3/share/hadoop/mapreduce hadoop jar hadoop-mapreduce-examples-3.1.3.jar pi 1000 1000
后面2个数字参数的含义: 第1个1000指的是要运行1000次map任务 …
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SELECT employee_id, first_name, last_name, hire_date, salary
FROM employees
ORDER BY first_name; --按字母,默认升序
ORDER BY hire_date ASC; --升序
ORDER BY hire_date DESC; --降序SELECT employee_id, first_name, last_name, hire_date, salary
F…