Help converting problem to sql solution

Hi

I cannot seem to find a proper sql query for my problem.

Input: (small set)

TicketNr|CustomerKey|

11 | 1

11 | 2

22 | 1

22 | 3

33 | 4

33 | 5

44 | 6

55 | 7

66 | 7

77 | 8

88 | 8

88 | 9

Output:

CustomerKey|NewKey

1 | 1

2 | 1

3 | 1

4 | 2

5 | 2

6 | 3

7 | 4

8 | 5

9 | 5

Explanation :

One ticket can contain muliple customers. I want to create a new Key bases on all customers that can be linked to each other.

CustomerKey 1 is used in Tickets 11 and 12 so all customer keys connecting to these tickets must be converted to on. That means that CustomerKey's 1,2 and 3 are combined.

I have tried subqueries/Ranks/first_value but cannot seem to get it to work correctly

Test code if anyone is interested

Any help appreciated!

USE [TestDb]
GO

DROP TABLE [dbo].[InputTable]
CREATE TABLE [dbo].[InputTable]
(
	[TicketNr] [int] NULL,
	[CustomerKey] [int] NULL
) ON [PRIMARY]

INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (11,1)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (11,2)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (22,1)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (22,3)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (33,4)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (33,5)

INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (44,6)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (55,7)

INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (66,7)

INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (77,8)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (88,8)
INSERT INTO [dbo].[InputTable]   ([TicketNr],[CustomerKey]) VALUES   (88,9)




GO