report builder ,create file with TAB

[ang21]

HI,
I need to create file a.txt with REPORT BUILDER be like this:
sum(a)||ch(9)|| sum(b)
1 ||a1)||ch(9)|| b1
2 ||a2)||ch(9)|| b2
3 ||a3)||ch(9)|| b3
..
.
.
n ||an)||ch(9)|| bn



result of my report is file but instead mark "TAB" there is space

first row I create with :

function CF_sumrowFormula return varchar2 is
tm varchar(1):= chr(9);
begin
sumrow:= ltrim(to_charcs_a,'999999'))||tm ||
ltrim(to_charcs_b,'999999'))||;
return(sumrow);
end;



another with:

function CF_rowFormula return varchar2 is
tm varchar(1):= chr(9);
begin
sumrow:= ltrim(to_charn,'999999'))||tm ||
ltrim(to_chara,'999999'))||tm ||
ltrim(to_charb,'999999'))||;
return(sumrow);
end;


Thanks .