NexusDB

drop function if exists getVarDatum;
create function getVarDatum
(
  aYear integer,
  aMonth integer
)
returns date
begin
  declare date_string varchar(10);
  set date_string = cast(aYear as char(4)) || '-' ||
  case 
    when aMonth < 10 then '0'||cast(aMonth as char(1))
  else
    cast(aMonth as char(2))
  end || '-' || '01';
  return cast(date_string as date);
end;