SQL Way To Suppress Repeated Values

This is a problem I usually solve with procedural code, but I am wondering how/if it could be done with SQL queries.

A simple one to many query like:

Select inv.invnbr, inv.freight, invline.quantity, invline.partnbr, invline.cost from inv inner join invline on inv.id = invline.InvID

Returns something like:

invnbr freight quantity partnbr cost

100 50 3 abc 50
100 50 6 def 65
100 50 10 ghi 70

Is there way I can rewrite the query, or add a subquery such that the result set would be:

invnbr freight quantity partnbr cost



100 50 3 abc 50

100 0 6 def 65

100 0 10 ghi 70

Eg, the freight value, which comes from the one/header table, would show up in only one of the lines for invnbr 100?

Many thanks
Mike Thomas