Question

我是php，mysql的新手。

我使用了四列，companyname，issuedwt，receiptwt＆amp;我的数据库中workloss。

我使用以下查询来获得已发行的wtwt，receiptwt＆amp; workloss。

$result = mysql_query("SELECT SUM(issuedwt) AS IssuedTotal, SUM(receiptwt) AS ReceiptTotal, SUM(workloss) AS Balance FROM `worksheet`")
or die(mysql_error());

我想使用基于companyname的过滤选项。（即company1，company2，company3）

如果我过滤company1，我只需要company1。我该怎么办？

Answer 1

您只需使用companyname子句过滤WHERE：

SELECT  
  SUM(issuedwt) AS IssuedTotal, 
  SUM(receiptwt) AS ReceiptTotal,
  SUM(workloss) AS Balance 
FROM `worksheet`
WHERE compamnyname = 'company1' -- for example

这将仅为IssuedTotal提供ReceiptTotal，Balance和company1。

但是，如果您想获得companyname和总计的列表，请使用GROUP BY companyname，但您仍然可以过滤公司名称：

SELECT companyname, 
  SUM(issuedwt) AS IssuedTotal, 
  SUM(receiptwt) AS ReceiptTotal, 
  SUM(workloss) AS Balance 
FROM `worksheet`
GROUP BY companyname

Answer 2

在查询中添加“group by”选项将让mysql知道哪些元素属于一起，并且它将计算每组的总和：

"SELECT 
  SUM(issuedwt) AS IssuedTotal, 
  SUM(receiptwt) AS ReceiptTotal, 
  SUM(workloss) AS Balance 
  FROM worksheet 
  group by companyname"

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

您可以随时使用“where”选项限制显示哪些公司，（从TABLE中选择COLUMN = VALUE）但我假设您想要获取每个公司的数据;然后只使用分组。

Answer 3

试试这个：

SELECT SUM(issuedwt) AS IssuedTotal, SUM(receiptwt) AS ReceiptTotal, 
       SUM(workloss) AS Balance 
FROM `worksheet`
WHERE companyname = 'company1';

如果您想要公司明智的数据而不是使用以下查询：

SELECT companyname, SUM(issuedwt) AS IssuedTotal, SUM(receiptwt) AS ReceiptTotal, 
       SUM(workloss) AS Balance 
FROM `worksheet`
GROUP BY companyname;

Answer 4

使用GROUP BY子句和您的查询：

SELECT companyname, SUM(issuedwt) AS IssuedTotal, SUM(receiptwt) AS ReceiptTotal,
SUM(workloss) AS Balance FROM `worksheet`
GROUP BY companyname

如何获得过滤数据的总和

4 个答案: