问题描述
大家好，
我有一个主表和明细表.对应于master中的ID，我在明细表中将有2/更多行.基于详细信息的ID，我在另一个表(例如table3)中有值.这意味着，如果我有2行详细信息，我将在table3中有2行.表3中有一个字段licensecount，该行的两行值都相同.我需要基于mastertable中的ID查找该licensecount的计数.
问题是当我加入这些表并接受SUM(table3.licensecount)时，我会添加作为结果添加的重复值.例如:如果licensecount是20，我得到的是40，我应该得到的是20..
谁能帮助我.在此先感谢
Hi guys,
I have a master table and detail table.Corresponding to an ID in master i will have 2/more rows in detail table. Based on the ID of detail i have values in another table say table3. That means if i have 2 rows in detail i will have 2 rows in table3. There is a field licensecount in table 3 and both rows wil have same values for that column. I need to find count of that licensecount based on the id in the mastertable.
The problem is when i join these table and take SUM(table3.licensecount) i ger the duplicate values added as result. For ex: if the licensecount is 20 what i get is 40 where i should be getting is 20..
Can anyone pls help me out. Thanks in advance
推荐答案
select count(licensecount) from
table1,table2,table3
where
table2.sameid= table3.sameid
and table2.id = table1.id
谢谢
Milind
Thanks
Milind
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