SQL Errors on "Products Purchased" report in Admin

Hi,

I am on Open Cart 1.4.9, getting a few SQL errors.

Error: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET SQL_MAX_JOIN_SIZE=# if the SELECT is okay
Error No: 1104
SELECT * FROM `order` o LEFT JOIN `order_product` op ON (o.order_id = op.order_id) WHERE o.order_status_id > '0' GROUP BY model

Any ideas?

Thanks
Anthony