Insert data into datagridview based on indicator in cell

Hi

I have a datagridview with data populated in Col 1 and Col 2. The user captures data in Col 3, which can be Numeric,AlphaNumeric or Date type data. The data in Co1 and Col 3 must be inserted into one of 3 tables:
                        tbNumeric OR
                        tbAlphanumeric OR
                        tbDate
based on the indicator in Col 2 (d_date OR d_Alpha OR d_Num). AND only if data is supplied in Col 3.

Further, i have the insert statements for the 3 tables.

Question: How do i iterate through the rows in the datagridview and fire the appropriate INSERT Statement based on the Indicator in Col 2?

Thanks