Get specific columns from join without join syntax? - sql-server

Question

Is there another way to write this?
SELECT src.ID, factDeviceBuild.ID
FROM #factDeviceBuild as src
INNER JOIN AppsFlyer.FactDeviceBuild AS factDeviceBuild
ON src.[DimDevice_Id] = factDeviceBuild.[DimDevice_Id] AND
src.[DimDeviceModel_Id] = factDeviceBuild.[DimDeviceModel_Id] AND
src.[DimPlatform_Id] = factDeviceBuild.[DimPlatform_Id] AND
src.[DimOSVersion_Id] = factDeviceBuild.[DimOSVersion_Id] AND
src.[DimSDKVersion_Id] = factDeviceBuild.[DimSDKVersion_Id] AND
src.[DimCarrier_Id] = factDeviceBuild.[DimCarrier_Id] AND
src.[DimOperator_Id] = factDeviceBuild.[DimOperator_Id]
I've been trying to do some different things (that don't work) like this
SELECT *, factDeviceBuild.ID
FROM #factDeviceBuild
WHERE EXISTS (
SELECT [DimDevice_Id], [DimDeviceModel_Id], [DimPlatform_Id],
[DimOSVersion_Id], [DimSDKVersion_Id], [DimCarrier_Id],
[DimOperator_Id]
FROM AppsFlyer.FactDeviceBuild AS factDeviceBuild
)
or like this (also doesn't work):
SELECT factDeviceBuild.ID,
factDeviceBuild.[ID]
FROM (
SELECT [DimDevice_Id], [DimDeviceModel_Id], [DimPlatform_Id],
[DimOSVersion_Id], [DimSDKVersion_Id], [DimCarrier_Id],
[DimOperator_Id]
FROM AppsFlyer.FactDeviceBuild AS factDeviceBuild
INTERSECT
SELECT [DimDevice_Id], [DimDeviceModel_Id], [DimPlatform_Id],
[DimOSVersion_Id], [DimSDKVersion_Id], [DimCarrier_Id],
[DimOperator_Id]
FROM AppsFlyer.#factDeviceBuild AS factDeviceBuild
) AS A
I'm just playing around with some query tuning. EXCEPT and INTERSECT are particularly interesting because of the way they treat NULLS.
Obviously I could use a CROSS JOIN or OUTER JOIN to construct my INNER JOIN form scratch, but I don't see a particular gain there.

Answer 1

I believe you are looking for something like this:
SELECT src.ID, fact.ID
FROM #factDeviceBuild as src
INNER JOIN AppsFlyer.FactDeviceBuild AS fact
ON EXISTS (
SELECT src.DimDevice_Id, src.DimDeviceModel_Id, src.DimPlatform_Id,
src.DimOSVersion_Id, src.DimSDKVersion_Id, src.DimCarrier_Id,
src.DimOperator_Id
INTERSECT
SELECT fact.DimDevice_Id, fact.DimDeviceModel_Id, fact.DimPlatform_Id,
fact.DimOSVersion_Id, fact.DimSDKVersion_Id, fact.DimCarrier_Id,
fact.DimOperator_Id
)
Using this INTERSECT syntax (instead of the usual conditions) has the advantage of treating NULL-s as the same values. For example, if only the DimCarrier_Id and DimOperator_Id columns would allow NULL-s, the equivalent condition would need be:
SELECT src.ID, fact.ID
FROM #factDeviceBuild as src
INNER JOIN AppsFlyer.FactDeviceBuild AS fact
ON src.DimDevice_Id = fact.DimDevice_Id AND
src.DimDeviceModel_Id = fact.DimDeviceModel_Id AND
src.DimPlatform_Id = fact.DimPlatform_Id AND
src.DimOSVersion_Id = fact.DimOSVersion_Id AND
src.DimSDKVersion_Id = fact.DimSDKVersion_Id AND
(src.DimCarrier_Id = fact.DimCarrier_Id OR src.DimCarrier_Id IS NULL AND fact.DimCarrier_Id IS NULL) AND
(src.DimOperator_Id = fact.DimOperator_Id OR src.DimOperator_Id IS NULL AND fact.DimOperator_Id IS NULL)

Answer 2

Following is same
SELECT src.ID, factDeviceBuild.ID
FROM #factDeviceBuild as src, AppsFlyer.FactDeviceBuild AS factDeviceBuild
WHERE
src.[DimDevice_Id] = factDeviceBuild.[DimDevice_Id] AND
src.[DimDeviceModel_Id] = factDeviceBuild.[DimDeviceModel_Id] AND
src.[DimPlatform_Id] = factDeviceBuild.[DimPlatform_Id] AND
src.[DimOSVersion_Id] = factDeviceBuild.[DimOSVersion_Id] AND
src.[DimSDKVersion_Id] = factDeviceBuild.[DimSDKVersion_Id] AND
src.[DimCarrier_Id] = factDeviceBuild.[DimCarrier_Id] AND
src.[DimOperator_Id] = factDeviceBuild.[DimOperator_Id]

Answer 3

Without either data or a visualization of the expected result, my guess is you need to "unpivot" the 7 id types into less columns, which reduces the join syntax complexity. e.g.:
select
src.id, f.fact_id, ca.id_type, ca.id_value
from #factDeviceBuild as src
cross apply (
values
('DimDevice_Id',src.[DimDevice_Id])
,('DimDeviceModel_Id',src.[DimDeviceModel_Id])
,('DimPlatform_Id',src.[DimPlatform_Id])
,('DimOSVersion_Id',src.[DimOSVersion_Id])
,('DimSDKVersion_Id',src.[DimSDKVersion_Id])
,('DimCarrier_Id',src.[DimCarrier_Id])
,('DimOperator_Id',src.[DimOperator_Id])
) ca (id_type, id_value)
inner join (
select
fact.id fact_id, ca.id_type, ca.id_value
from AppsFlyer.FactDeviceBuild AS fact
cross apply (
values
('DimDevice_Id',fact.[DimDevice_Id])
,('DimDeviceModel_Id',fact.[DimDeviceModel_Id])
,('DimPlatform_Id',fact.[DimPlatform_Id])
,('DimOSVersion_Id',fact.[DimOSVersion_Id])
,('DimSDKVersion_Id',fact.[DimSDKVersion_Id])
,('DimCarrier_Id',fact.[DimCarrier_Id])
,('DimOperator_Id',fact.[DimOperator_Id])
) ca (id_type, id_value)
where ca.id_value IS NOT NULL
) as f on ca.id_type = f.id_type and ca.id_value = f.id_value
Note I have not used the "unpivot" feature of TSQL as I prefer the syntax you see above. There is NO additional performance disadvantage when using this apply/values syntax.
NB: all 7 of those id type columns must be "compatible" data types for the "unpivot" to work without error. All 7 as integer for example, which would make the id_value a column of integers.