sql數據分析

查詢一個月（5月）每天加分記錄

SELECT
	date(t.date),
	count(1)
FROM
	t_addmcoinrecord t
WHERE
	date BETWEEN '2019-05-01'
AND '2019-05-30'
GROUP BY
	date(t.date)
ORDER BY date(t.date)

查詢近四年每月使用數據量（按日期順序查詢）
SELECT
YEAR(date), – 年份(日期) –
MONTH(date),
count(1)
FROM
t_addmcoinrecord t
WHERE
date BETWEEN ‘2015-05-01’
AND ‘2019-05-30’
GROUP BY
YEAR(date),
MONTH(date)

查詢近四年每月數據量（順序查詢）

查詢多少員工

select count(1) from t_user

查詢加分次數
select count(1) from t_addmcoinrecord t

查詢當月（5月）加分類型數據量（倒序）

SELECT
	t.typeID,
	tt.type_Name,  -- 類型表名稱 --
	count(1)
FROM
	t_addmcoinrecord t
LEFT JOIN t_type tt on tt.type_ID = t.typeID  -- 查詢加分表ID和類型表ID相同的數據 --
where
  date BETWEEN '2019-05-01' AND '2019-05-30'
GROUP BY
  t.typeID
ORDER BY
	count(tt.type_Name) DESC  -- 按照類型數量倒序排序 --

查詢當月（5月）部門數據量（倒序）

select 
	t.departmentName,
	count(1)
FROM
	t_addmcoinrecord t
WHERE
  date between '2019-05-01' and '2019-05-30'
GROUP BY
	t.departmentName
ORDER BY
	count(t.departmentName) DESC

將數據做成表格形式如下：

sql訓練：