Combine columns from tables into single table - sql-server

Question

I have four tables with data I want to put the respective total columns from each in a different column. However, I would like to match on dealerId. So if there is a dealerId in Table 1 and Table 3 that are the same, they should be a single row.
Table 1
dealerId | t1 Total Amount
---------+---------------
1 | 123
2 | 456
Table 2
dealerId | t2 Total Amount
---------+----------------
3 | 111
4 | 222
5 | 333
Table 3
dealerId | t3 Total Amount
---------+----------------
1 | 555
3 | 565
6 | 888
Table 4
dealerId | t4 Total Amount
---------+----------------
1 | 88
2 | 99
3 | 11
Desired Outcome
dealerId | t1Total Amount | t2Total Amount | t3 Total Amount | t4 Total Amount
---------+----------------+----------------+-----------------+-----------------
1 | 123 | null | 555 | 88
2 | 456 | null | null | 99
3 | null | 111 | 565 | 11
4 | null | 222 | null | null
5 | null | 333 | null | null
6 | null | null | 888 | null
I have basically created views (I don't know if this is the correct term for it) and tried to UNION ALL them, but this only gives me a single column with all the totals.
SELECT *
FROM
(
SELECT o.DealerId, Sum(oi.Amount) as T1_Total
FROM ....
) AS T1
UNION ALL
SELECT *
FROM
(
SELECT o.DealerId, Sum(oi.Amount) as T2_Total
FROM ....
) AS T2
UNION ALL
...
-- repeat for T3 and T4

Answer 1

You can also use the pivot operator:
select dealerId, T1, T2, T3, T4
from (
select dealerId, 'T1' as Src, "t1 Total Amount" as Amt from T1
union all
select dealerId, 'T2' , "t2 Total Amount" from T2
union all
select dealerId, 'T3' , "t3 Total Amount" from T3
union all
select dealerId, 'T4' , "t4 Total Amount" from T4
) vert
pivot (sum(Amt) for Src in (T1,T2,T3,T4)) horiz
Results:
dealerId T1 T2 T3 T4
----------- ----------- ----------- ----------- -----------
1 123 NULL 555 88
2 456 NULL NULL 99
3 NULL 111 565 11
4 NULL 222 NULL NULL
5 NULL 333 NULL NULL
6 NULL NULL 888 NULL

Answer 2

Try doing something like this:
with all_dealer_ids AS (
SELECT DISTINCT dealerId
FROM Table1
UNION
SELECT DISTINCT dealerId
FROM Table2
UNION
SELECT DISTINCT dealerId
FROM Table3
UNION
SELECT DISTINCT dealerId
FROM Table4
)
SELECT adi.dealerId, SUM(t1.TotalAmount) As T1TotalAmount, SUM(t2.TotalAmount) As
T2TotalAmount, SUM(t3.TotalAmount) AS T3TotalAmount, SUM(t4.TotalAmount) AS T4TotalAmount
FROM all_dealer_ids adi
LEFT JOIN Table1 t1
ON adi.dealerId = t1.dealerId
LEFT JOIN Table2 t2
ON adi.dealerId = t2.dealerId
LEFT JOIN Table3 t3
ON adi.dealerId = t3.dealerId
LEFT JOIN Table4 t4
ON adi.dealerId = t4.dealerId
GROUP BY adi.dealerId
ORDER BY adi.dealerId ASC

Answer 3

You'll want to use JOIN instead of UNION to accomplish what you're looking for. UNIONs are typically used to stack data, which is why you are seeing all your data in one column. You can try something like this to accomplish what you are looking for.
SELECT COALESCE(t1_totals.dealerID, t2_totals.dealerID, t3_totals.dealerID, t4_totals.dealerID) AS dealerId
, t1_totals.t1_total_amount
, t2_totals.t2_total_amount
, t3_totals.t3_total_amount
, t4_totals.t4_total_amount
FROM (
SELECT dealerID, sum(amount) AS t1_total_amount FROM t1 GROUP BY t1.dealerID
) AS t1_totals
FULL JOIN (
SELECT dealerID, sum(amount) AS t2_total_amount FROM t2 GROUP BY t2.dealerID
) AS t2_totals
ON t2_totals.dealerID = t1_totals.dealerID
FULL JOIN (
SELECT dealerID, sum(amount) AS t3_total_amount FROM t3 GROUP BY t3.dealerID
) AS t3_totals
ON t3_totals.dealerID = t1_totals.dealerID
FULL JOIN (
SELECT dealerID, sum(amount) AS t4_total_amount FROM t4 GROUP BY t4.dealerID
) AS t4_totals
ON t4_totals.dealerID = t1_totals.dealerID
ORDER BY dealerId