As we do not have access to the related JomSocial code can you debug a bit more and what kind of call they initiated? It must be something in the lines of their modules.
16 JFDatabase->query() /home/ACCOUNTUSERNAME/public_html/components/com_community/models/activities.php:271
17 interceptDB->setRefTables() /home/ACCOUNTUSERNAME/public_html/plugins/system/jfdatabase/jfdatabase_inherit.php:642
18 interceptDB->_getFieldCount() /home/ACCOUNTUSERNAME/public_html/plugins/system/jfdatabase/intercept.jdatabasemysql.php:225
Also is it possible that you switch on the debug mode and PHP error reporting to see if there are more information posted why the classes do have an issue there.
Last but not least, what MySQL Version are you using? And also are you using the mysqli
driver for your database or the standard one? Looks like the standard one while the i version is the recommended!
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