embedded table

HSMorales

I have a report with 2 tables binded to 2 different datasets.
Table_1 has a header section and a detail section.
In the detail section of Table_1, I embedded Table_2.
Table_2 has a filter equating a field to a field in table_1.
The dataset for table_2 has a computed column of Row_Count to count the number of rows.

How can I suppress the detail section of Table_1 when Table_2 row_Count is 0 ??
I have a border around the header of Table_1 and when there is no detail, the border line seems to double in width.

I am doing it this way because I am unable to use a merged dataset.

Thanks for all Your Help.
BIRT 3.7.0