Getting difference from values of two different SQL Statements

Question

Hello,
I have two SQL Queries like the following:
1. Statement:
SELECT name, SUM(a1), SUM(b1),SUM(c1),SUM(d1)
FROM table 1, table 2
WHERE ...
GROUP BY name
2. Statement:
SELECT name, SUM(a2), SUM(b2),SUM(c2),SUM(d2)
FROM table 3, table 4
WHERE ...
GROUP BY name
I need now a combination of these SQL Statements in one Statement where the result should be the following records
name, a1-a2 as a, b1-b2 as b, c1-c2 as c, d1-d2 as d
Name is a VARCHAR and in both queries the values of the field name are the same
all other fields are integer.
I hope someone can help me.
Regards

Answer 1

You can use this
with t1 as (
          SELECT name, SUM(a1) as a1, SUM(b1) as b1,SUM(c1) as c1,SUM(d1) as d1
          FROM table 1, table 2
          WHERE ...
          GROUP BY name
     ), t2 as (
          SELECT name, SUM(a2) as a2, SUM(b2) as b2,SUM(c2) as c2,SUM(d2) as d2
          FROM table 3, table 4
          WHERE ...
          GROUP BY name     
     ), tt as (
          select name
          from t1
          union
          select name
          from t2
select *
from tt
     natural left outer join t1
     natural left outer join t2
where a1 <> a2
     or b1 <> b2
     or c1 <> c2
     or d1 <> d2Bye Alessandro