You should only pass the data that you're going to use in the computation, I don't think that you need to pass dates, strings, ...
You should extract the simple data from each row to pass them by using several buffers, one buffer per field, one value per row. Let's assume that you have three rows and two fields, you'll build two buffers and you'll put three values in each buffer.
It's possible to use "structs" in OpenCL but maybe it's overkill in your case.