SELECT 招聘岗位,COUNT(招聘岗位) AS 频数统计 FROM 招聘信息

GROUP BY 招聘岗位 ORDER BY 频数统计 DESC

SELECT 招聘单位,COUNT(招聘单位) AS 频数统计 FROM 招聘信息

GROUP BY 招聘单位 ORDER BY 频数统计 DESC 

SELECT 招聘单位,AVG(REPLACE(SUBSTR(薪资区间,1,2),'K',''))*1000 AS 平均最低薪酬,

AVG(REPLACE(REPLACE(SUBSTR(薪资区间,4,3),'K',''),'-',''))*1000 AS 平均最高薪酬 FROM `招聘信息`  GROUP BY 招聘单位 ORDER BY 平均最低薪酬 DESC;