主题：关于合并多个查询结果中的表达式列问题

Dim k As String = Tables("资金流向明细表").current("账号名称")
Dim g As Date = Tables("资金流向明细表").current("开始时间")
Dim f As Date = Tables("资金流向明细表").current("结束时间")

Dim jb1 As New SQLJoinTableBuilder("查询表1","资金账号")
jb1.C
jb1.AddTable("资金账号","账号编号","资金支出单","账号编号")
jb1.AddCols("付款单编号","{资金支出单}.单据类型","账号名称", "(-支出金额)","付款日期")
jb1.filter = "账号名称 ='" & k & "'"

Dim jb2 As New SQLJoinTableBuilder("查询表1","资金账号")
jb2.C
jb2.AddTable("资金账号","账号编号","资金收入单","账号编号")
jb2.AddCols("收款单编号","{资金收入单}.单据类型","账号名称", "收入金额","收款日期")
jb2.filter = "账号名称 ='" & k & "'"

Dim jb3 As New SQLJoinTableBuilder("查询表1","资金账号")
jb3.C
jb3.AddTable("资金账号","账号编号","工厂销售收款单","账号编号")
jb3.AddCols("收款单编号","{工厂销售收款单}.表名代码","收款账号","应收款金额","收款日期")
jb3.filter = "账号名称 ='" & k & "'"

以上代码中，由于jb3中的应收款金额为表达式列，造成列名无效，请问怎么办