Fetch data from multiple rows

Hi,

I am passing in put @z to the stored procedure like below

Input parameter :

Declare @z varchar(50)

SET @z = 1

Table data :

x     y         z
12  test     5,2,3,4
1    test1   1,7

I want to pass the @z parameter as 1 to  z  column in the above table

I want to output like below

Out  Put