updated format of import data

src/Sql/Sql.sqlproj

@@ -190,5 +190,6 @@
     <Build Include="dbo\Stored Procedures\OrganizationUser_UpdateWithCollections.sql" />
     <Build Include="dbo\Stored Procedures\CollectionUser_Delete.sql" />
     <Build Include="dbo\Stored Procedures\GroupUser_ReadByOrganizationId.sql" />
+    <Build Include="dbo\Stored Procedures\GroupUser_UpdateUsers.sql" />
   </ItemGroup>
 </Project>

src/Sql/dbo/Stored Procedures/GroupUser_UpdateUsers.sql

@@ -0,0 +1,46 @@
+CREATE PROCEDURE [dbo].[GroupUser_UpdateUsers]
+    @GroupId UNIQUEIDENTIFIER,
+    @OrganizationUserIds AS [dbo].[GuidIdArray] READONLY
+AS
+BEGIN
+    SET NOCOUNT ON
+
+    DECLARE @OrgId UNIQUEIDENTIFIER = (
+        SELECT TOP 1
+            [OrganizationId]
+        FROM
+            [dbo].[Group]
+        WHERE
+            [Id] = @GroupId
+    )
+
+    ;WITH [AvailableUsersCTE] AS(
+        SELECT
+            [Id]
+        FROM
+            [dbo].[OrganizationUser]
+        WHERE
+            [OrganizationId] = @OrgId
+    )
+    MERGE
+        [dbo].[GroupUser] AS [Target]
+    USING 
+        @OrganizationUserIds AS [Source]
+    ON
+        [Target].[GroupId] = @GroupId
+        AND [Target].[OrganizationUserId] = [Source].[Id]
+    WHEN NOT MATCHED BY TARGET
+    AND [Source].[Id] IN (SELECT [Id] FROM [AvailableUsersCTE]) THEN
+        INSERT VALUES
+        (
+            @GroupId,
+            [Source].[Id]
+        )
+    WHEN NOT MATCHED BY SOURCE
+    AND [Target].[GroupId] = @GroupId
+    AND [Target].[OrganizationUserId] IN (SELECT [Id] FROM [AvailableUsersCTE]) THEN
+        DELETE
+    ;
+
+    -- TODO: Bump account revision date for all @OrganizationUserIds
+END