oracle - Multiple column update -

i have execute following lines of update in procedure. can update in single line. 1 table present here.

    update magic_table set first_col=0,last_col=my_value first_col not null;     update magic_table set second_col=0,last_col=my_value second_col not null;     update magic_table set third_col=null,last_col=my_value third_col not null; 

if give performance improvements?

update magig_table     set first_col  = nvl2(first_col , 0, first_col ),         second_col = nvl2(second_col, 0, second_col),         third_col  = nvl2(third_col , 0, third_col ),         last_col   = my_value   first_col    not null or         second_col   not null or         third_col    not null;