update set 按條件更新不同字段

if(@b1<>'-' )

begin

update table set f1=@f1,f2=@f2,f3=@f3 where id= 100

end

else

if(@b2<>'-')

begin

update table set begin f4=@f4,f5=@f5,f6=@f6 where id= 100

end