I am wondering if this query can be modified to achieve what I want:
SELECT
cv.[ID]
,cv.[CustomValue]
,cf.[SpecialInformationId]
FROM #CustomFields cf
FULL OUTER JOIN #CustomValues cv ON cf.SpecialInformationId = cv.id
This returns all cv.Id's. It also returns any unmatched cf.SpecialInformationId's with a NULL for the cv information. What I actually want is for each instance of cv, I want every cf to show. cf is a lookup table. In this instance there are 12 values, but that varies everytime the query runs. Here is an example:
What this query currently returns:
cv.id cv.customvalue cf.specialinformationid
1 003 1
1 abc 2
2 004 1
2 1/1/2010 4
2 开发者_如何学JAVA abc 2
3 009 1
4 003 1
4 acb 2
4 1/2/2010 4
What I want it to return:
cv.id cv.customvalue cf.specialinformationid
1 003 1
1 abc 2
1 NULL 3
1 NULL 4
1 NULL 5
2 004 1
2 abc 2
2 NULL 3
2 1/1/2010 4
2 NULL 5
3 009 1
3 NULL 2
3 NULL 3
3 NULL 4
3 NULL 5
4 003 1
4 acb 2
4 NULL 3
4 1/2/2010 4
4 NULL 5
A Left join cannot be used because there are only 12 rows in the lookup table so if a left join is used the same result will be achieved as the full outer join.
This is a spinoff of my other question: SQL 2 tables always return all rows from 1 table match existing on other
Thanks
I believe a CROSS JOIN will achieve the results you're looking for.
The problems are arising because your Table2 is not really a 'vehicle' table. Because the VehicleId does not uniquely identify a record in that table. This is where all of the confusion is coming from. So to solve that and get your problem to work I did a select distinct on table2 against the values in table 1 (I also did a select distinct for clarity, but it was not necessary.) Hope this helps.
CREATE TABLE #Table1 (Id INT)
CREATE TABLE #Table2 (VehicleID INT, Value VARCHAR(50), Table1ID INT)
INSERT INTO #Table1 VALUES (1),(2),(3),(4),(5)
INSERT INTO #Table2 VALUES (1, 't', 1),(1, 'q', 2),(3, 'w', 3),(3, 'e', 4),(4, 't', 1),(5, 'e', 1),(5, 'f', 2),(5, 'g', 4)
SELECT * FROM #Table1
SELECT * FROM #Table2
SELECT t2.VehicleID, t2.Value
FROM ( SELECT t2.VehicleId, t1.Id
FROM ( SELECT DISTINCT
VehicleId
FROM #Table2 ) t2
CROSS JOIN ( SELECT Id
FROM #Table1 ) t1 ) Base
LEFT JOIN #Table2 t2
ON Base.VehicleId = t2.VehicleID
AND Base.Id = t2.Table1ID
WHERE (Base.VehicleId BETWEEN 1 AND 3)
DROP TABLE #Table1
DROP TABLE #Table2
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