主题：懵了，求大神指点

命令窗口里测试

Dim qssj As Date = "2014-9-1"
Dim jzsj As Date = "2014-9-2"
Dim dfs As Double = DataTables("员工业绩子表").SQLCompute("sum(包厢个数)","日期>= '" & qssj & "' And 日期<= '" & jzsj & "'")
output.Show(dfs)

dfs的值为0，实际是有数据的，哪里有问题呢？