最近12個月，每週一組

Question

我有一個表REGDATE列，註冊日期（YYYY-MM-DD HH：MM：SS）。我想顯示一個直方圖（ExtJS），以瞭解用戶註冊的年份。我希望在過去的十二個月內就當前日期進行此操作，並按星期分組。

任何提示？

Answer 1

在MySQL

：

SELECT COUNT(*), DATE_FORMAT(regdate, "%X%V") AS regweek FROM table GROUP BY regweek; 

或

SELECT COUNT(*), YEARWEEK(NOW(), 2) as regweek FROM table GROUP BY regweek; 

PostgreSQL中：

SELECT COUNT(*), EXTRACT(YEAR FROM regdate)::text || EXTRACT(WEEK FROM regdate)::text AS regweek FROM table GROUP BY regweek; 

Answer 2

提示：（SQL）

SELECT CONVERT (VARCHAR(7), REGDATE, 120) AS [RegistrationMonth] 
FROM ... 
GROUP BY CONVERT (VARCHAR(7), REGDATE, 120) 
ORDER BY CONVERT (VARCHAR(7), REGDATE, 120) 

Answer 3

FWIW PostgreSQL中，Karaszi有問題的解答，但有一個更快的查詢：

SELECT date_trunc('week', REGDATE) AS "Week" , count(*) AS "No. of users" 
FROM <<TABLE>> 
WHERE REGDATE > now() - interval '12 months' 
GROUP BY 1 
ORDER BY 1; 

我基於這一關的Ben Goodacre

Answer 4

工作也許這？

select to_char(REGDATE,'WW') "Week number", 
     count(*) "number of signups", 
from YOUR_TABLE 
where REGDATE > current_date-365 
group by to_char(REGDATE,'WW') 
order by to_char(REGDATE,'WW')