Hello,
1) I’m not sure about this, it’s your site. This plugin does not come bundled with our theme, so we don’t have any recommendations about this. Read the plugin description and decide if you need it or not.
2) If you take a look at links you’ll see that it comes to settings of the third-party plugin (Abandoned Cart Lite for WooCommerce), not to our theme settings or files. We don’t see any queries in our theme that could cause the mentioned error and any links to our settings in the error logs, so check the third-party plugins that you use. For example, plugin mentioned above.
Also, if you check the WooCommerce > Status > Logs you’ll see that GreenPay by Green Payment Processing plugin generates log files everyday http://prntscr.com/qq5cou So, clear from the plugin author if you need these logs and disable them in plugin settings if not.
Regards