There are many occasions in programs where you need to manipulate strings of characters that are delimited by a particular character, such as a comma, or a space. This function enables you to extract a substring from the string at a specified occurence of the delimter.
declare @Data varchar(255)
set @Data = 'A,B,C,D,E'
print dbo.field(@data,',',2,2)
Result:-
B,C