Pass GridView Rows to SQL Database in one postback.

Question

Hi.... 

I am using 3 tier architecture i want a fucntion to pass grdiview rows to Data access layer and save it to a table in SQL Server 2005 Express edition. 
Can anyone give an idea to save each row without opening connection at each time. Here my problem is if i have 500 rows , 500 times it is opening connection in Data access layer........ 

Thanks and Regards 
Sankar 
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