CSV Data (Comma Seperated value)

Declare @table table (CityName varchar(50))

insert into @table values ('London')
insert into @table values ('Birmingham')
insert into @table values ('Manchester')
insert into @table values ('Glasgow')

1._________________________________________________________________
declare @csv as varchar(500)
select @csv = case  when @csv is null then ''
else @csv + ',' end + CityName from @table
select @csv as csv

2.__________________________________________________________________
declare @csv as varchar(500)
SELECT @CSV = COALESCE(@csv + ', ','') + CityName
FROM @table
select @csv as csv

3.__________________________________________________________________
declare @csv as varchar(500)
set @csv = (select CityName + ',' from @table for xml path(''))
select @csv as csv