Extract array of JSONs to columns in SQL

I have the following table with JSON collections:

As can be see in the example not all records have a value, and those that have the length of the array vary (by a maximum of 9 items). Ideally I would like to create a column for each slider that contains its entry value, but there are about 400 million records and about 80 different sliders.

So I would be happy to create a columns only for certain sliders, say 4 and 5 and get the following table.

Or alternatively create a table that will extract the json to the columns in the following way:

Both options are good and working for me, the only consideration is efficiency because as mentioned there are a millions of records (and maybe there are other options that are preferred and I have not thought about). It also important that each record be associated with its original id.

So far I tried the following proceeder, however even when I execute it on very small amount of rows (only 100) it took hours, so I guess something wrong.

DECLARE @NOTE_ID uniqueidentifier
DECLARE @USER_ID uniqueidentifier
DECLARE @SINGEL_SLIDER NVARCHAR(MAX)

DECLARE SLIDER_CURSOR CURSOR FOR SELECT [NoteID],[UserID],[SliderJSON]  FROM [dbo].[SmallData]
OPEN SLIDER_CURSOR

FETCH NEXT FROM SLIDER_CURSOR INTO @NOTE_ID, @USER_ID, @SINGEL_SLIDER
WHILE @@FETCH_STATUS = 0  
BEGIN

IF len(@SINGEL_SLIDER)>1
    BEGIN 

        IF OBJECT_ID('tempdb..#TMP') IS NOT NULL
        DROP TABLE #TMP 

        SELECT *
        INTO #TMP
        FROM OPENJSON(@SINGEL_SLIDER)

        DECLARE @SLIDER_VALUE NVARCHAR(MAX)

        DECLARE SLIDER_VALUE_CURSOR CURSOR FOR SELECT [value]  FROM #TMP
        OPEN SLIDER_VALUE_CURSOR
        FETCH NEXT FROM SLIDER_VALUE_CURSOR INTO  @SLIDER_VALUE
        WHILE @@FETCH_STATUS = 0  
        BEGIN

        IF OBJECT_ID('tempdb..#TMP1') IS NOT NULL
        DROP TABLE #TMP1

        SELECT *
        INTO #TMP1
        FROM OPENJSON(@SLIDER_VALUE)

        DECLARE @SLIDER_ID NVARCHAR(100)
        DECLARE @SLIDER_OPTION_ID  NVARCHAR(100)

        SET @SLIDER_ID = (SELECT [value] FROM #TMP1 WHERE [key] = 'Slider')
        SET @SLIDER_OPTION_ID = (SELECT [value] FROM #TMP1 WHERE [key] = 'Value')

        IF @SLIDER_ID = 4 
            BEGIN
                UPDATE [dbo].[SmallData]
                SET [4] = @SLIDER_OPTION_ID
                WHERE [NoteID] = @NOTE_ID
            END
        ELSE IF @SLIDER_ID = 7 
            BEGIN
                UPDATE [dbo].[SmallData]
                SET [7] = @SLIDER_OPTION_ID
                WHERE [NoteID] = @NOTE_ID
            END
        ELSE IF @SLIDER_ID = 1
            BEGIN
                UPDATE [dbo].[SmallData]
                SET [1] = @SLIDER_OPTION_ID
                WHERE [NoteID] = @NOTE_ID
            END
        ELSE IF @SLIDER_ID = 10
            BEGIN
                UPDATE [dbo].[SmallData]
                SET [10] = @SLIDER_OPTION_ID
                WHERE [NoteID] = @NOTE_ID
            END
        ELSE IF @SLIDER_ID = 43
            BEGIN
                UPDATE [dbo].[SmallData]
                SET [43] = @SLIDER_OPTION_ID
                WHERE [NoteID] = @NOTE_ID
            END
        ELSE IF @SLIDER_ID = 15
            BEGIN
                UPDATE [dbo].[SmallData]
                SET [15] = @SLIDER_OPTION_ID
                WHERE [NoteID] = @NOTE_ID
            END
        ELSE IF @SLIDER_ID = 18
            BEGIN
                UPDATE [dbo].[SmallData]
                SET [18] = @SLIDER_OPTION_ID
                WHERE [NoteID] = @NOTE_ID
            END
    END

 FETCH NEXT FROM SLIDER_VALUE_CURSOR INTO @SLIDER_VALUE
END 

CLOSE SLIDER_VALUE_CURSOR  
DEALLOCATE SLIDER_VALUE_CURSOR 

FETCH NEXT FROM SLIDER_CURSOR INTO @NOTE_ID, @USER_ID, @SINGEL_SLIDER 
END 

CLOSE SLIDER_CURSOR  
DEALLOCATE SLIDER_CURSOR 

I would appreciate any help on this subject.