define my_super_stream every HOUR =
  parent_stream
  {
    string field1
    int field2
    int cnt = Sum(<<1>>) // Like count(*)
  }

define other_stream every HOUR = @anti_join
{
  stream1
  {
    string field1
  }
  stream2 [DAY @ -HOUR] // window of 1 day and offset of - 1h
  {
    string field1
  }
}