An exception has been thrown during the rendering of a template ("SQLSTATE[42000]: Syntax error or access violation: 1055 Expression #1 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column 'ctc_billing_db.p.priority' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by") in "mod_order_index.phtml" at line 20.

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