VB6 ADO Disconnected记录集不返回任何记录

Question

我正在创建、打开MySQL数据库的记录集，然后断开连接。这对一个查询有效，但对数据库中存在行的另一个查询返回0条记录。在它工作的地方，我也可以从记录集中删除记录。

返回记录的查询：

sql = "select convert(v.wonotes using UTF8) as WonData, v.wo_cat_id, v.id As wo_desc_id, v.line_no as line_no, " & _
      " v.wo_id as wo_id, v.prop_id as prop_id, convert(v.description using UTF8) as description, v.cat_id as cat_id, " & _
      " v.completion_date as completion_date from vw_property_wo_desc v " & _
      " where v.wo_cat_id= 6 and **(v.wo_status = 'completed' or v.wo_status = 'approved')** " & _
      " and v.wonotes is not null and v.wonotes<> '' "

不返回记录的查询：

sql = "select convert(v.wonotes using UTF8) as WonData, v.wo_cat_id, v.id As wo_desc_id, v.line_no as line_no, " & _
      " v.wo_id as wo_id, v.prop_id as prop_id, convert(v.description using UTF8) as description, v.cat_id as cat_id, " & _
      " v.completion_date as completion_date from vw_property_wo_desc v " & _
      " where v.wo_cat_id= 6 and **v.wo_status = 'unassigned'** " & _
      " and v.wonotes is not null and v.wonotes<> '' "

没有其他变化。

如果我将游标类型更改为adOpenDynamic，查询会返回记录，但我无法断开它的连接。这只是为了证明数据库中有满足该查询的记录。

断开连接的记录集代码：

With rsToUse
    If .State = adStateOpen Then .Close
    .ActiveConnection = GetConnection
    .Source = sql
    .CursorLocation = adUseClient
    .CursorType = adOpenForwardOnly
    .LockType = adLockBatchOptimistic
    .Open
    If .EOF Then
        .Close
        Exit Function
    End If
    .ActiveConnection = Nothing
End With

我没什么主意了，请帮帮我。

Answer 1

这是我用来从SQL Server数据库获取断开连接的记录集的代码。我怀疑它也适用于MySQL数据库（当然，除了连接字符串）。

Public Function GetRecordset(ByVal SQL As String) As ADODB.Recordset
    Dim DB As ADODB.Connection
    Dim RS As ADODB.Recordset
    Set DB = CreateObject("ADODB.Connection")
    DB.ConnectionString = globalConnectionString
    DB.CursorLocation = adUseClient
    DB.CommandTimeout = 0
    Call DB.Open
    Set RS = CreateObject("ADODB.Recordset")
    RS.CursorLocation = adUseClient
    Call RS.Open(SQL, DB, adOpenForwardOnly, adLockReadOnly)
    Set RS.ActiveConnection = Nothing
    Set GetRecordset = RS
    Set RS = Nothing
    DB.Close
    Set DB = Nothing
End Function

这个确切的代码已经生产了至少5年，没有任何问题。我鼓励你试一试。

我认为使用断开连接的记录集的神奇组合是确保连接对象的CursorLocation设置为UseClient，并且记录集对象是ForwardOnly和LockReadOnly。