运行时错误'-2147217904(80040e10)':至少一个参数没有被指定值

Sub test11()
  Dim cnn As New ADODB.Connection
  Dim rs As New ADODB.Recordset
  Dim sql As String
  Dim mybook As String
  mybook = ThisWorkbook.FullName
  With cnn
    If Application.Version = "11.0" Then
      .Provider = "microsoft.jet.oledb.4.0"
      .ConnectionString = "extended properties=""excel 8.0;HDR=YES;"";data source=" & mybook
    Else
      .Provider = "microsoft.ACE.oledb.12.0"
      .ConnectionString = "extended properties=""excel 12.0;HDR=YES;"";data source=" & mybook
    End If
    .Open
  End With
  sql = "select * from [期中$a2:e] where 编码 in (select 编码 from [期末$a2:e])"
  rs.Open sql, cnn, adOpenKeyset, adLockOptimistic
  With Worksheets("期中期末共有")
    .Range("a4").CopyFromRecordset rs
  End With

  rs.Close
  sql = "select * from [期末$a2:e] where 编码 in (select 编码 from [期中$a2:e])"
  rs.Open sql, cnn, adOpenKeyset, adLockOptimistic
  With Worksheets("期中期末共有")
    .Range("g4").CopyFromRecordset rs
  End With

  rs.Close
  sql = "select * from [期中$a2:e] where 编码 not in (select 编码 from [期末$a2:e])"
  rs.Open sql, cnn, adOpenKeyset, adLockOptimistic
  With Worksheets("期中有期末没有")
    .Range("a4").CopyFromRecordset rs
  End With

  rs.Close
  sql = "select * from [期末$a2:e] where 编码 not in (select 编码 from [期中$a2:e] where not isnull(编码))"
  rs.Open sql, cnn, adOpenKeyset, adLockOptimistic
  With Worksheets("期末有期中没有")
    .Range("a4").CopyFromRecordset rs
  End With
End Sub

运行上述宏时，出现以下错误：运行时错误'-2147217904(80040e10)':至少一个参数没有被指定值，点调试时显示错误在：rs.Open sql, cnn, adOpenKeyset, adLockOptimistic
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