主题：[求助]SQLGroupTableBuilder统计语句执行错误

请高手指点以下语句错误出在哪。

Dim b As New SQLGroupTableBuilder("统计表","OrderDetail")
b.C
b.AddTable("OrderDetail","OrderID","OrderINF","OrderID")
b.AddTable("OrderDetail","UserID","UserINF","UserID")
b.Groups.AddDef("Region")
b.Groups.AddDef("{OrderINF}.OrderDate", DateGroupEnum.Year, "年")
b.Totals.AddDef("成交额")
b.Build
MainTable = Tables("统计表")

表OrderINF与表OrderDetail有同名列OrderDate。当执行以上语句时报错，报错信息为：列名"OrderDate”不明确