的QuickFix

Question

我正在学习如何在MySQL中编写查询，我有一个包含交易的表格，希望获得总计1. revenues sold through the full life span，2. Revenues in a day，3. Revenues in a week和{{1 }}。所有这些都返回具有相同列的表。

所以我有两个表，交易表保存我的所有交易和价格表，保存所有项目的价格，在购买物品时，我从价格表中获取itemid，以便我获取价格事务我需要加入这两个，这是我的表结构：

价格表

4. Revenues in a month

交易表

         |priceid | itemName | price |
         -----------------------------
         |1      |Bread     | 20    |

我知道如何使用3个查询获得一天，一周和一个月的总收入，收入，但想要一种方法在一个查询中获取所有3个值

我所知道的是

        |transactionid |pricefk |  transactiondate |
        --------------------------------------------
        |112           |1       |2018-03-22 19:15:05|

获取所有终身收入

SELECT  SUM(p.price) as totalrevenue FROM transaction_table t JOIN price_tb p ON p.priceid = t.pricefk

获得一天的收入

SELECT  SUM(p.price) as totalrevenue FROM transaction_table t JOIN price_tb p ON p.priceid = t.pricefk  where t.transactiondate >= NOW() - INTERVAL 1 DAY

获得一周的收入

SELECT  SUM(p.price) as totalrevenue FROM transaction_table t JOIN price_tb p ON p.priceid = t.pricefk  where YEARWEEK(t.transactiondate)=YEARWEEK(NOW())

获得一个月的收入

如何在一个查询中组合所有这些查询？

Answer 1

的QuickFix

您可以将它们包装在一个选择中，如下所示：

SELECT 
(SELECT SUM(p.price) FROM transaction_table t JOIN price_tb p ON p.priceid = t.pricefk) 
as lifetimeRevenue,
(SELECT  SUM(p.price) FROM transaction_table t JOIN price_tb p ON p.priceid = t.pricefk  where t.transactiondate >= NOW() - INTERVAL 1 DAY) 
as dayRevenue,
(SELECT  SUM(p.price) FROM transaction_table t JOIN price_tb p ON p.priceid = t.pricefk  where YEARWEEK(t.transactiondate)=YEARWEEK(NOW())) 
as weekRevenue,
(SELECT  SUM(p.price) FROM transaction_table t JOIN price_tb p ON p.priceid = t.pricefk  WHERE MONTH(t.transactiondate) = MONTH(CURRENT_DATE()) AND YEAR(t.transactiondate) = YEAR(CURRENT_DATE())) 
as monthRevenue

在这里工作小提琴：http://www.sqlfiddle.com/#!9/70ef6/5

使其更简单

您没有使用任何外键，它们将有助于保持数据的完整性，并且通过使用它可以使查询变得更加简单。

您可以在transaction_table的创建表语句中添加类似的内容。

foreign key (pricefk) references price_tb(priceid)

之后，在表的所有连接语句中，只包含表名：

SELECT 
(SELECT SUM(price) FROM transaction_table,price_tb)
as lifetimeRevenue,
(SELECT  SUM(price) FROM transaction_table,price_tb where transactiondate >= NOW() - INTERVAL 1 DAY) 
as dayRevenue,
(SELECT  SUM(price) FROM transaction_table,price_tb where YEARWEEK(transactiondate)=YEARWEEK(NOW())) 
as weekRevenue,
(SELECT  SUM(price) FROM transaction_table,price_tb WHERE MONTH(transactiondate) = MONTH(CURRENT_DATE()) AND YEAR(transactiondate) = YEAR(CURRENT_DATE())) 
as monthRevenue

完整的工作小提琴：http://www.sqlfiddle.com/#!9/9f333/6

（注意：我已将pricefk列重命名为priceid作为标准做法。）

Answer 2

所有这些查询只返回一行，所以如果你需要在一行上得到结果，你可以尝试使用交叉连接

  select t1.totalrevenue_lifetime, t2.totalrevenue_day, t3.totalrevenue_week , t4.totalrevenue_month
  from (
      SELECT  SUM(p.price) as totalrevenue_lifetime 
      FROM transaction_table t 
      JOIN price_tb p ON p.priceid = t.pricefk
  ) t1 
  CROSS JOIN (
    SELECT  SUM(p.price) as totalrevenue_day 
    FROM transaction_table t 
    JOIN price_tb p ON p.priceid = t.pricefk  
    where t.transactiondate >= NOW() - INTERVAL 1 DAY

  ) t2 
  CROSS JOIN (
    SELECT  SUM(p.price) as totalrevenue_week 
    FROM transaction_table t 
    JOIN price_tb p ON p.priceid = t.pricefk  
    where YEARWEEK(t.transactiondate)=YEARWEEK(NOW())
  ) t3
  CROSS JOIN (
      SELECT  SUM(p.price) as totalrevenue_month 
      FROM transaction_table t 
      JOIN price_tb p ON p.priceid = t.pricefk  
      WHERE MONTH(t.transactiondate) = MONTH(CURRENT_DATE())
      AND YEAR(t.transactiondate) = YEAR(CURRENT_DATE())
  ) t4

将独立选择查询的结果合并到一个表

2 个答案:

的QuickFix

使其更简单