Question

我对adodb参数查询存在以下问题，该查询因错误而失败或返回空记录集。但是，类似的DAO查询也会成功。

这一切都在MS Access中

首先，SQL-Find_Post_Code-设计为采用一个或两个参数：

PARAMETERS [Local] Text ( 255 ), FState Text ( 255 );
SELECT PCodes.postcode, PCodes.locality, PCodes.state, PCodes.long, PCodes.lat
FROM PCodes
WHERE (((PCodes.locality) Like "*" & [Local] & "*") AND ((PCodes.state)=[FState])) OR (((PCodes.locality) Like "*" & [Local] & "*") AND ((([PCodes].[state]) Like [FState]) Is Null))
ORDER BY PCodes.locality;

现在有了ADODB功能：

Public Function GetPostCode(varLocality As Variant, varState As Variant) As String
'//Purpose: Return Post Code for a varLocality and/or varState

  Dim cmd As New ADODB.Command
  Dim rst As New ADODB.Recordset

On Error GoTo Handle_err

  With cmd
    .CommandText = "Find_Post_Code"
    .CommandType = adCmdStoredProc
    Set .ActiveConnection = CurrentProject.Connection
    .Parameters.Append .CreateParameter("Local", adVarChar, adParamInput, , CStr(Nz(varLocality, "")))
    .Parameters.Append .CreateParameter("FState", adVarChar, adParamInput, , CStr(Nz(varState, "")))
    rst.CursorType = adOpenStatic
    Set rst = .Execute
  End With

  If Not rst.EOF Then
    GetPostCode = rst!postcode
  End If
  rst.Close

Handle_err:
  If Err Then
    MsgBox "Error " & Format(Err.Number) & " " & Err.Description, vbCritical, AppTitle
    Err.Clear
  End If

  Set rst = Nothing
  Set cmd = Nothing

End Function

这失败，并显示错误消息：错误3708参数对象定义不正确。提供的信息不一致或不完整。

如果我将参数强制转换为adBSTR，则没有错误，但是结果记录集没有数据

但是，如果我使用以下DAO函数，一切都很好

Public Function GetPostCode2(Locality As String, State As String) As String
'//Purpose: Return Post Code for a varLocality and/or varState

  Dim db As Database
  Dim qd As DAO.QueryDef
  Dim prmLocality As DAO.Parameter
  Dim prmFSTate As DAO.Parameter
  Dim rst As DAO.Recordset

On Error GoTo Handle_err

  Set db = CurrentDb
  Set qd = db.QueryDefs("Find_Post_Code")
  Set prmLocality = qd.Parameters!Local
  prmLocality.Value = Locality

  Set prmFSTate = qd.Parameters!FState
  prmFSTate.Value = State

  Set rst = qd.OpenRecordset

  If Not rst.EOF Then
    GetPostCode2 = rst!postcode
  End If

  rst.Close

Handle_err:
  If Err Then
    MsgBox "Error " & Format(Err.Number) & " " & Err.Description, vbCritical, AppTitle
    Err.Clear
  End If
  Set rst = Nothing
  Set prmLocality = Nothing
  Set prmFSTate = Nothing
  Set qd = Nothing
  Set db = Nothing

End Function

我不希望在ADODB和DAO之间交换和更改以实现我的目标。非常感谢您的帮助

Answer 1

感谢您的输入。解决方法如下： 1.按照HansUp的建议修改SQL语句。

PARAMETERS [Local] Text ( 255 ), FState Text ( 255 );
SELECT PCodes.postcode, PCodes.locality, PCodes.state, PCodes.long, PCodes.lat
FROM PCodes  WHERE (((PCodes.locality) Like "%" & [Local] & "%") AND ((PCodes.state)= 
[FState])) OR (((PCodes.locality) Like "%" & [Local] & "%") AND ((([PCodes].[state]) 
Like [FState]) Is Null)) ORDER BY PCodes.locality;

有趣的是，如果在Access UI中使用此查询，则不会返回任何值

将ADO参数设置为adBSTR-adVarChar和adVarWChar都返回错误3708参数对象定义不正确。提供的信息不一致或不完整。

vba adodb参数查询失败

1 个答案: