When SQL Mode ONLY_FULL_GROUP_BY activated, which is a default since version 5.7, the dashboard widget throws an exception.
Expression #3 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'typo3.tx_tracking_pageview.sys_language_uid' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by
When SQL Mode ONLY_FULL_GROUP_BY activated, which is a default since version 5.7, the dashboard widget throws an exception.
Expression #3 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'typo3.tx_tracking_pageview.sys_language_uid' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by