tIncome: in_id (pr_k), qnt(количество прихода), cur_qnt (количество сейчас) ...
tOutcome: out_id (pr_k), in_id (fk), qnt(количество реализации)... 

create procedure sp_del_out_in (d date)
as
begin
  delete from tOutcome o
  where exists
  (
  select i.in_id
  from Tincome i, Toutcome o
  where  (i.in_id=o.in_id) and (i.indate<'01/01/2018')
  group by i.in_id
  having i.qnt-sum(o.qnt)<0.001
  )

qIn.open;                                                                    
  while not qIn.Eof do begin
    qOutDelete.Params[0].AsInteger:= qInIn_id.AsInteger;  
    qOutDelete.ExecSQL;

    qInDelete.Params[0].AsInteger:=qInIn_id.asInteger;
    qIn.ExecSQL;

    qIn.Next;
  end;

create procedure sp_del_out_in (d date)
as
begin
for select i.in_id
from tIncome i, tOutcome o
where
 (i.qnt-(select sum(o.qnt) from tOutcome o where outdate<:d)<0.001) and
 (i.in_id=o.in_id)
into :in_id 
do 
begin
  delete from tOutcome where in_id = :in_id;
  delete from tIncome where in_id = :in_id;
end
end

 (i.qnt-(select sum(o.qnt) from tOutcome o where outdate<:d)<0.001)

create procedure pr_del_recg_recs (d date)
as
declare variable in_id numeric(10,4);
declare variable out_id numeric(10,4);
declare variable o_qnt numeric(10,4);
declare variable i_qnt numeric(10,4);
for  select i.in_id,i.qnt
     from tInCome i
     where i.indate < :d rows 10    -- limit of rows
   into :in_id, :i_qnt
do begin
   o_qnt=0;
   select sum(o.qnt)
        from tOutcome o
        where o.in_id = :in_id
        group by o.in_id
        having max(o.outdate) < :d
     into :o_qnt;

   if (i_qnt - o_qnt < 0.001) then
   begin
       delete from tInCome i where i.in_id=:in_id;
       delete from tOutCome o where o.in_id=:in_id;
   end
end