Thread: how to write querey return the unique CustomerId with the first CustomerName ?

hii ,sorry what do you mean by sure-fire signal ? yes i agree with you that the data is look bad , but i work on a huge data that which is extracted by the Customers them self so i can not edit any thing. many thanks

Member 3018046 wrote: hii ,sorry what do you mean by sure-fire signal It means that it is time to examine why you have 2 customer records with the same Id, but different names.

Maybe it ins't the best solution but you can use a group by (CustomerId), then you have to choose wich CustomerName is the choosen (min(CustomerName), max(CustomerName...). Sql: > select CustomerId, max(CustomerName) from Customer group by CustomerId.

You can even try this declare @tblcustomer table(customerid int,customername varchar(50)) insert into @tblcustomer select 12,'Jone' union all select 25,'Mark' union all select 25,'Marc' union all select 10,'AJ' select x.customerid ,x.customername from ( select ROW_NUMBER() over (partition by customerid order by customerid) as rn ,customerid ,customername from @tblcustomer)X(rn,customerid,customername)...

How do you know which is the first CustomerName? Is the 'first' name always the correct one?