After installing JoomSEF, there are SQL queries visible over my page, why is that?

This means that JoomSEF could not run the SQL query on your database. Please, check that Joomla has right privileges set to access all the DB tables. This error can also occure when there is some older version of needed table left in your database - try uninstalling JoomSEF, manually deleting the needed table and installing JoomSEF again. Always backup your database prior to doing such changes! Please note this especially occures after you had sh404sef installed previously. sh40sef will not remove its tables correctly, so you need to make sure they are removed before installing JoomSEF. If you had sh404sef component installed previously, please, check the related topic in our support forums for the right procedure: Installing JoomSEF after sh404sef.