Magento Version : 1.9.2.2

I have some Custom Options fields for my products which could potentially contain sensitive information. I do not want the data associated with the customer after I have fulfilled the order. I would therefore like to purge just the Custom Options data from the database.

I have crafted the following mysql query which removes ALL the "Custom Options" from both sales and quotes and it appears to work. Obviously I would limit this to just the orders I wanted to clear.

UPDATE `sales_flat_order_item` SET product_options='';
UPDATE `sales_flat_quote_item_option` SET VALUE='' WHERE (`code` NOT LIKE 'info_buyRequest' AND `code` NOT LIKE 'option_ids');

• Will the above queries purge all the "Custom Options" data from the database?
• Will clearing the data in this way cause any other problems within Magento ?
• Is there perhaps a better way of doing this than resorting to manually clearing the fields with a mysql query?