pgsql 分组查询，每组取10条

需求： 按照表的字段分组，然后每组取10条结果，返回即可

sql 如下：

SELECT
	* 
FROM (SELECT chk_id,feature_id,task_id, ROW_NUMBER () OVER (PARTITION BY chk_id ORDER BY chk_id) AS row_num 
      FROM ics_check_report 
      WHERE task_id = '10069' 
	) as a
WHERE a.row_num < 11

展示查询结果：

sql解释语法如下：

row_number() over( partition by col1 order by col2desc)

partition by chk_id ：要分组的字段

order by chk_id ： 要排序字段

row_number () ：为返回的记录定义各行编号