Get related tables not contains result - sql

Question

I have a DesignGroup table as:
+--------------------------------------+----------+
| DesignGroupId | Name |
+--------------------------------------+----------+
| 3A81C1FF-442F-4291-B8E2-7079D80920CF | Design 1 |
| 3238F4C6-7BA7-4B3F-9383-17702B0D1CC3 | Design 2 |
+--------------------------------------+----------+
Each DesignGroup can have multiple customers, so I have a table DesignGroupCustomers as:
+--------------------------------------+--------------------------------------+-------------+
| DesignGroupCustomerId | DesignGroupId (FK) | CustomerKey |
+--------------------------------------+--------------------------------------+-------------+
| D0828677-F295-46F7-BB85-65888D5A48B7 | 3A81C1FF-442F-4291-B8E2-7079D80920CF | 10 |
| 10C01BB9-1DDB-4DB4-BEC4-9539E030BF68 | 3A81C1FF-442F-4291-B8E2-7079D80920CF | 20 |
| F88C9F66-C0D9-EB11-8481-5CF9DDF6DC87 | 3238F4C6-7BA7-4B3F-9383-17702B0D1CC3 | 10 |
+--------------------------------------+--------------------------------------+-------------+
Each customer have a CustomerType as, customerTable:
+-------------+-------------+
| CustomerKey | CustTypeKey |
+-------------+-------------+
| 10 | 2 |
| 20 | 1 |
+-------------+-------------+
That I want to achieve is to get only this statement:
return only the DesignGroup who not have a customer with custTypeKey = 1
In this case it should return Design 2 because it does not have customer with custTypeKey = 1
I was thinking about CTE usage but I just have not idea how to get the desire result:
;WITH CTE
AS (SELECT
[DG].[DesignGroupId]
, ROW_NUMBER() OVER(PARTITION BY [DesignGroupCustomer]) AS [RN]
FROM [DesignGroup] AS [DG]
INNER JOIN [DesignGroupCustomer] AS [DGC] ON [DG].[DesignGroupId] = [DGC].[DesignGroupId]
INNER JOIN [Customer] AS [C] ON [DGC].[CustomerKey] = [C].[CustomerKey]
INNER JOIN [CustomerType] AS [CT] ON [C].[CustTypeKey] = [CT].[CustTypeKey])
SELECT
[DesignGroupId]
FROM [CTE] -- WHERE CustomerType NOT CONTAINS (1)

Answer 1

WITH temp AS (
SELECT DISTINCT
dgc.DesignGroupId AS DesignGroupId
FROM DesignGroupCustomers dgc
INNER JOIN customerTable ct
ON dgc.CustomerKey = ct.CustomerKey
WHERE ct.CustTypeKey = 1
)
SELECT
DesignGroupId
FROM DesignGroup
WHERE DesignGroupId NOT IN (
SELECT
DesignGroupId
FROM temp
)
Firstly, you can get all designgroups having CustTypeKey =1 and then get all other designgroups using NOT IN. Please let me know if you face any issues

Answer 2

You can use a subquery to return the design groups which have this customer type key of 1 and then LEFT JOIN the subquery on the design table and filter down to results that have a DesignGroupId of null (any design group that isn't included in the dataset of the subquery)
SELECT d.[DesignGroupId]
FROM [DesignGroup] AS d
LEFT JOIN
(
SELECT dgc.[DesignGroupId]
FROM [DesignGroupCustomer] AS dgc
ON dgc.[DesignGroupId] = d.[DesignGroupId]
INNER JOIN [Customer] AS c
ON c.[CustomerKey] = dgc.[CustomerKey]
WHERE c.[CustTypeKey] = 1
GROUP BY dgc.[DesignGroupId]
) x
ON x.[DesignGroupId] = d.[DesignGroupId]
WHERE x.[DesignGroupId] IS NULL