Find out latest transaction for particular Customers.

select * from  [dbo].[Transaction] order by name

ID	name	Transdate	Transnumber	Product
4	CP	2019-02-12 00:00:00.000	1004	TOY
7	CP	2019-03-01 00:00:00.000	1007	TOY
1	rahul	2019-02-02 00:00:00.000	1001	book
2	rahul	2019-02-12 00:00:00.000	1002	book
3	RAVI	2019-02-15 00:00:00.000	1003	TOY
5	RP	2019-02-13 00:00:00.000	1005	BOOK
8	RP	2019-02-28 00:00:00.000	1008	BOOK
6	SUMIT	2019-02-12 00:00:00.000	1006	BOOK

select max(Transdate),name,product from [dbo].[Transaction] group by product,name

transaction date	name	product
2019-03-01 00:00:00.000	CP	TOY
2019-02-12 00:00:00.000	rahul	book
2019-02-15 00:00:00.000	RAVI	TOY
2019-02-28 00:00:00.000	RP	BOOK
2019-02-12 00:00:00.000	SUMIT	BOOK