How do I declare a variable using dynamic SQL? - sql-server

Question

I am currently attempting to edit a pair of variables that are part of a larger stored procedure. These variables are currently set up like so:
DECLARE #Container_3Month_Avg money = (
SELECT AVG(cntr.[PricePerContainer])
FROM plx.[Part_v_Part_e]
OUTER APPLY (
SELECT TOP 3 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 1
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) cntr
)
DECLARE #Container_Last money = (
SELECT TOP 1 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 1
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
)
What I would like to do is modify these variables to be a little more complicated. [idContainerIndex] = 1 represents a subset of the data. I need to modify the code so that it combines the [PricePerContainer] values for two different [idContainerIndex] into a single variable. For instance, I need #Container_3Month_Avg to be the SUM of the AVG of the TOP 3 [PricePerContainer] for [idContainerIndex] = 1 and [idContainerIndex] = 14. The same applies for #Container_Last, I need this to be the SUM of the TOP 1 [PricerPerContainer] for [idContainerIndex] = 1 and [idContainerIndex] = 14.
This is just about as far as I got:
DECLARE #Container_3Month_Avg money = (
**fbx01avg + fbx01-ipiavg**
(
SELECT AVG(cntr.[PricePerContainer])
FROM plx.[Part_v_Part_e]
OUTER APPLY (
SELECT TOP 3 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 1
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) cntr
) fbx01avg
(
SELECT AVG(inbd.[PricePerContainer])
FROM plx.[Part_v_Part_e]
OUTER APPLY (
SELECT TOP 3 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 14
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) inbd
) fbx01-ipiavg
)
fbx01avg + fbx01-ipiavg => how do I write this bit of code?
DECLARE #Container_Last money = (
**fbx01 + fbx01-ipi**
(
SELECT TOP 1 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 1
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) fbx01
(
SELECT TOP 1 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 14
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) fbx01-ipi
)
fbx01 + fbx01-ipi => how do I write this bit of code?
The bolded text is really what I'm looking to accomplish in simple terms. I just need to add these two select statements together somehow to get a single return for each variable. Any assistance would be greatly appreciated.

Answer 1

Why not just:
DECLARE #Container_3Month_Avg money = (
(
SELECT AVG(cntr.[PricePerContainer])
FROM plx.[Part_v_Part_e]
OUTER APPLY (
SELECT TOP 3 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 1
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) cntr
)
+
(
SELECT AVG(inbd.[PricePerContainer])
FROM plx.[Part_v_Part_e]
OUTER APPLY (
SELECT TOP 3 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 14
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) inbd
)
)
Your actual queries are kinda weird though. You do an average of cntr.[PricePerContainer], but there's no condition between [Part_v_Part_e] and [PricePerContainer]
What's the purpose of plx.[Part_v_Part_e] at all.

Answer 2

I think this may have worked:
SELECT SUM(avgPricePerContainer) as avgPricePerContainer
FROM
(
(
SELECT AVG(cntr.[PricePerContainer]) as avgPricePerContainer
FROM plx.[Part_v_Part_e]
OUTER APPLY (
SELECT TOP 3 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 1
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) cntr
)
union all
(
SELECT AVG(inbd.[PricePerContainer]) as avgPricePerContainer
FROM plx.[Part_v_Part_e]
OUTER APPLY (
SELECT TOP 3 [PricePerContainer]
FROM [mtx].[ContainerIndexPrice]
WHERE 1 = 1
AND [idContainerIndex] = 14
AND [DateDeactivated] IS NULL
ORDER BY [DateMonthStart] DESC
) inbd
)
) s