This page explains how to troubleshoot your ODBC connection to BigCommerce in DBxtra.
Due to incompatibilities between DBxtra and BigCommerce, leaving the SQL dialect property to its default might present various issues. To resolve compatibility issues, set the property to MS Access 2000/XP/2003 or ANSI SQL/2003 for DBxtra version 11.0.1 or newer, and to ANSI SQL/2003 for versions prior to 11.0.1.