SQL Server 2017

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DECLARE @ColumnList VARCHAR(MAX)
	DECLARE @sqlCommand VARCHAR(MAX)

;WITH CTE(Class,Name,Date)
	AS
	(
		SELECT A.Cl Class,B.Name,B.Date
		FROM (
			SELECT 'A' Cl UNION ALL SELECT 'B' UNION ALL SELECT 'C' UNION ALL SELECT 'D'
		)A
		INNER JOIN 
		(
			SELECT 'John' Name,'15/06/2019' Date,'AB' Class UNION ALL
			SELECT 'John','14/06/2019','B' UNION ALL
			SELECT 'John','13/06/2019','C' UNION ALL
			SELECT 'Tom','14/06/2019','C' UNION ALL
			SELECT 'Tom','13/06/2019','D'
		)
		B
		ON  B.Class LIKE '%' + A.Cl + '%'
	)

SELECT  @ColumnList =

STUFF((SELECT DISTINCT  ('],[' +  A.Class)
            FROM CTE A
            --ORDER BY (A.Class) 
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)')
        ,1,1,'')+']'
	FROM CTE

SET @sqlCommand= 
	N'
	SELECT 
	Name,A ClassA, B ClassB,C ClassC,D ClassD,
	A+B+C+D ClassCount
	FROM
	(
		SELECT Name,'+SUBSTRING(@ColumnList,2,LEN(@ColumnList))+'
		FROM
		(
			SELECT A.Cl Class,B.Name,B.Date
			FROM (
				SELECT ''A'' Cl UNION ALL SELECT ''B'' UNION ALL SELECT ''C'' UNION ALL SELECT ''D''
			)A
			INNER JOIN 
			(
				SELECT ''John'' Name,''15/06/2019'' Date,''AB'' Class UNION ALL
				SELECT ''John'',''14/06/2019'',''B'' UNION ALL
				SELECT ''John'',''13/06/2019'',''C'' UNION ALL
				SELECT ''Tom'',''14/06/2019'',''C'' UNION ALL
				SELECT ''Tom'',''13/06/2019'',''D''
			)
			B
			ON  B.Class LIKE ''%'' + A.Cl + ''%''
		)A
		PIVOT(
			COUNT(Date)
			FOR Class IN('+SUBSTRING(@ColumnList,2,LEN(@ColumnList))+')
		)PVT
	)AA'

--PRINT @sqlCommand
    EXEC (@sqlCommand)

Name	ClassA	ClassB	ClassC	ClassD	ClassCount
John	1	2	1	0	4
Tom	0	0	1	1	2