DIH outer joins

[Rui António da Cruz Pereira]

I have queries with outer joins defined in some entities and for the 
same root object I can have two or more lines with different objects, 
for example:

Taking the following 3 tables, andquery defined in the entity with outer 
joins between tables:
Table1 -> Table2 -> Table3
I can have the following lines returned by the query:
Table1Instance1 -> Table2Instance1 -> Table3Instance1
Table1Instance1 -> Table2Instance1 -> Table3Instance2
Table1Instance1 -> Table2Instance2 -> Table3Instance3
Table1Instance2 -> Table2Instance3 -> Table3Instance4

I wanted to have a single document per root object instance (in this 
case per Table1 instance) but with the values from the different lines 
returned.

Is it possible to have this behavior in DataImportHandler? How?

Thanks in advance,
   Rui Pereira