select
  TAB1.FIELD1,
  extract(year from TAB1.DATE_FIELD),
  extract(month from TAB1.DATE_FIELD),
  sum(
  case
    when TAB2.FIELD2 = 0 then
        TAB2.FIELD3 * case TAB1.FIELD4
                        when 13 then
                            TAB2.FIELD5
                        else -TAB2.FIELD5
                      end
    else 0
  end),
  sum(
  case
    when TAB2.FIELD2 <> 0 then
        TAB2.FIELD3 * case TAB1.FIELD4
                        when 13 then
                            TAB2.FIELD5
                        else -TAB2.FIELD5
                      end
    else 0
  end)
from
    TAB2
  inner join
    TAB1 using (FIELD6)
group by
         TAB1.FIELD1, extract(year from TAB1.DATE_FIELD),
         extract(month from TAB1.DATE_FIELD)