Question

I’m thinking of building query from these 2 tables (on SQL Server 2008). I have 2 tables as shown below:

Table 1

 MemberId  . MemberName .  Percentage .  Amount1
 00000001    AAA                 1.0     100
 00000002    BBB                 1.2     800
 00000003    ZZZ                 1.0     700

Table 2

 MemberId  . MemberName .  Percentage .  Amount2
 00000002    BBB                 1.5     500
 00000002    BBB                 1.6     100
 00000002    BBB                 1.6     150

The result I want is

 MemberId  . MemberName .  Percentage .  Amount . NettAmount
 00000001    AAA                 1.0      100     100
 00000002    BBB                 1.2      800      50 <-- 800-(500+100+150)
 00000002    BBB                 1.5      500     500
 00000002    BBB                 1.6      250     250
 00000003    ZZZ                 1.0      700     700

50 comes from 800 in Table1 minus sum of Amount2 in table2 for MemberID=00000002

Plz someone help me to build the query to reach this result.

Thank you in advance.

Answer 1

What you need to do is something like this:

1. Select from Table1
2. Do a GROUP BY select from Table2
3. Join the results of those two queries by MemberId

SQL code:

SELECT ... FROM Table1
INNER JOIN (SELECT MemberId, SUM(Amount2) FROM Table2 GROUP BY MemberId) Agg
ON Table1.MemberId = Agg.MemberId

Then you should be able to select “Amount1 – Amount2” from the join.

HTH.