MySQL:一个 SQL 语句中多个条件的总和列表 [英] MySQL: list of sum for several conditions in one SQL statement

问题描述

我的 MySQL 语句有问题:

I have a problem with a MySQL statement:

select sum(x) as "sum", "01.06.2010" as "date" from (
   select distinct a.id as ID, a.dur as x from b_c 
      inner join c on b_c.c_id = c.id 
      inner join a on c.id = a.c_id 
      inner join a_au on a.id = a_aud.id 
      inner join d on a_au.rev = d.rev 
      where 
         b_c.b_id = 30 and 
         a_au.stat != 1 and 
         DATE(FROM_UNIXTIME(rtime)) = DATE('2010-06-01')
) AS SubSelectTable;

此语句返回一行，其中包含sum"和date"列.

This statement returns one row with the colums "sum" and "date".

现在我不仅有一个日期('2010-06-01')，我有很多日期我必须得到它的 sum()，但不是在一行中.我希望每天有一个结果行.

Now I have not only one date ('2010-06-01'), I have many dates I have to get the sum() of it, but not in one single row. I want to have per day one result row.

例如，上面的语句返回了我

So, for example, the statement above returns me

sum            date
-------------------
 20      01.06.2010

现在我有日期 2010-06-01, 2010-06-02, 2010-06-03, ...我能做的是为每个日期编写一个更改日期的 sql 语句.所以如果我有 10 个日期，我将有 10 条数据库的 sql 语句.但是我确实想要一个 SQL 语句，结果不应该是所有给定日期的总和，我希望每个日期有一个结果行.所以结果应该是这样的:

Now I have the dates 2010-06-01, 2010-06-02, 2010-06-03, ... What I can do is to write for every date one sql statement changing the DATE. So if I have 10 dates, I will have 10 sql statements for the database. But I did want it with one SQL statement, and the result should not be the sum of all given dates, I want to have one result row per date. So the result should like that:

sum            date
-------------------
 20      01.06.2010
133      02.06.2010
 19      03.06.2010
 88      04.06.2010
...             ...

我该怎么做?有人知道吗?

How can I do this? Does anyone know?

提前致谢&最好的问候.

Thanks a lot in advance & Best Regards.

推荐答案

使用 mysql GROUP BY 命令.完全未经测试的代码示例:

Use the mysql GROUP BY command. Completely untested code example:

select sum(x) as "sum", date as "date" from (
   select distinct a.id as ID, a.dur as x, DATE(FROM_UNIXTIME(rtime)) as date from b_c 
      inner join c on b_c.c_id = c.id 
      inner join a on c.id = a.c_id 
      inner join a_au on a.id = a_aud.id 
      inner join d on a_au.rev = d.rev 
      where 
         b_c.b_id = 30 and 
         a_au.stat != 1
) AS SubSelectTable
group by date;

见:http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html

这篇关于MySQL:一个 SQL 语句中多个条件的总和列表的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！