sql - 如何将年月与日分开？创建一个统计每月雇用人数的视图

Question

创建一个统计每个月雇佣人数的视图。按年排序列表，然后按月及其雇用人数。

但是因为包含“DAYS”，所以输出没有组合成一行。如何将年月与日分开？

任何人都可以改进我的答案吗？

这是我的脚本

SELECT YEAR (hireDate) AS "YEAR ", MONTH (hireDate) AS "MONTH",  COUNT (hireDate) "hires for each month"
FROM employee
GROUP BY  hireDate;

标签： sqlsortingselectgroup-bycount

Answer 1

您需要按总年数和月数进行分组。

SELECT YEAR (hireDate) AS "YEAR ", MONTH (hireDate) AS "MONTH",  COUNT (hireDate) "hires for each month"
FROM employee
GROUP BY  YEAR (hireDate), MONTH (hireDate)