.net - ADODB .NET 互操作游标

Question

我不明白为什么会这样……

我有以下代码：

        var connection = new Connection();
        connection.CursorLocation = CursorLocationEnum.adUseClient;
        connection.ConnectionString = GetOdbcConnectionString(connectionString);
        connection.Open();

        var rs = new Recordset();
        rs.CursorType = CursorTypeEnum.adOpenStatic;
        rs.CursorLocation = CursorLocationEnum.adUseClient;
        rs.LockType = LockTypeEnum.adLockBatchOptimistic;
        // this issues the SQL SELECT * FROM Test
        rs.Open("SELECT * FROM Test", connection); 
        rs.ActiveConnection = null;
        rs.Close();
        rs = null;

        var rs2 = new Recordset();
        rs2.CursorType = CursorTypeEnum.adOpenStatic;
        rs2.CursorLocation = CursorLocationEnum.adUseClient;
        rs2.LockType = LockTypeEnum.adLockBatchOptimistic;

        /* this doesn't output the expected SQL...it outputs:
declare @p1 int
set @p1=180150003
declare @p3 int
set @p3=4
declare @p4 int
set @p4=1
declare @p5 int
set @p5=-1
exec sp_cursoropen @p1 output,N'SELECT * FROM Test',@p3 output,@p4 output,@p5 output
select @p1, @p3, @p4, @p5

*/

        rs2.Open("SELECT * FROM Test", connection);

如果我Marshal.ReleaseComObject(rs)在打开 rs2 之前手动操作，第二个记录集会发出与第一个相同的简单 SQL，而不使用游标。从第一个 rs 开始，一定有什么东西挂在上面……但我不知道当连接和记录集都设置了 OpenStatic 和 UseClient 时，它是什么、为什么或为什么会导致使用游标。

Answer 1

在这个问题上敲了半天，终于找到了问题所在：

DRIVER={SQL Server};

需要更改为

Provider=SQLOLEDB;