Scalar Function Coalesce Rows - sql

Question

I am trying to get a scalar function to work that combines all the rows of display values.
When I run my distinct query I get results I expect:
SELECT DISTINCT [tblMSC_Notes].[Display]
FROM [tblMSC_Notes]
INNER JOIN [tblUnits_Notes] ON [tblUnits_Notes].[NotesID] = [tblMSC_Notes].[NoteID]
WHERE (([tblMSC_Notes].[Display] IS NOT NULL) AND ([tblUnits_Notes].[UnitID] = 15))
ORDER BY [tblMSC_Notes].[Display]
Rows Displayed:
♦
ML
No Cloak
What I am trying to do now is output the Display as a single field "♦, ML, No Cloak"
Looking at the various examples I think I am close but I keep getting errors with the query:
BEGIN
-- Declare the return variable here
DECLARE #Result nvarchar(Max)
SET #Result = ''
WITH Display_CTE (Display)
AS
(
SELECT DISTINCT [tblMSC_Notes].[Display]
FROM [tblMSC_Notes]
INNER JOIN [tblUnits_Notes] ON [tblUnits_Notes].[NotesID] = [tblMSC_Notes].[NoteID]
WHERE (([tblMSC_Notes].[Display] IS NOT NULL) AND ([tblUnits_Notes].[UnitID] = #UnitID))
ORDER BY [tblMSC_Notes].[Display]
)
SET #Result = (SELECT COALESCE(#Result + ', ','') as DisplayResult
FROM (
SELECT [tblMSC_Notes].[Display]
FROM [tblMSC_Notes]
WHERE [Display] IN (SELECT Display FROM Display_CTE)
ORDER BY [tblMSC_Notes].[Display]
)
)
-- Return the result of the function
RETURN #Result
END
I was going to make this a scalar function in another query.
Here is some sample data from the tblMSC_Notes table:
ID UnitID NotesID
1 1513 154
2 1513 154
3 5032 152
4 5032 155
5 5033 152
6 5033 155
7 5033 43
8 5034 43
9 5034 152
10 5034 155
11 5035 152
12 5035 155
13 5035 43
Here is join using the Note ID
ID UnitID NotesID Display
1 1513 154 LB
2 1513 154 LB
3 5032 152 AL
4 5032 155 PL
5 5033 152 AL
6 5033 155 PL
7 5033 43 N
8 5034 43 N
9 5034 152 AL
10 5034 155 PL
Mohd - Thanks for the help so I would just need to change my create function to:
CREATE FUNCTION [dbo].[fnAnnex03_MasterShipChart_Notes] (
-- Add the parameters for the function here
#UnitID int
)
RETURNS nvarchar(Max)
AS
BEGIN
-- Declare the return variable here
DECLARE #Result nvarchar(Max)
SET #Result = ''
SET #Result = (SELECT string_agg(DISTINCT [tblMSC_Notes].[Display], ',') FROM [tblMSC_Notes] INNER JOIN [tblUnits_Notes] ON [tblUnits_Notes].[NotesID] = [tblMSC_Notes].[NoteID] WHERE (([tblMSC_Notes].[Display] IS NOT NULL) AND ([tblUnits_Notes].[UnitID] = #UnitID)) ORDER BY [tblMSC_Notes].[Display])
-- Return the result of the function
RETURN #Result
END
GO

Answer 1

Could you please provide a FIDDLE for this example with data.
You just need to use string_agg in this query as below:
SELECT string_agg(DISTINCT [tblMSC_Notes].[Display], ',')
FROM [tblMSC_Notes]
INNER JOIN [tblUnits_Notes] ON [tblUnits_Notes].[NotesID] = [tblMSC_Notes].[NoteID]
WHERE (([tblMSC_Notes].[Display] IS NOT NULL) AND ([tblUnits_Notes].[UnitID] = #UnitID))
ORDER BY [tblMSC_Notes].[Display]