需求:統計當前數據庫user_tasks表中,不一樣status字段值對應的記錄條數及佔比sql
sql語句:數據庫
SELECT `status`, number, concat(round(number / total * 100.00, 2), '%') percent FROM ( SELECT * FROM ( SELECT `status`, COUNT(1) number FROM `user_tasks` GROUP BY `status` ) t1 INNER JOIN( SELECT COUNT(1) total FROM `user_tasks` ) t2 ON 1 = 1 ) t
解析:函數