select 查询中的字符串计算，长度大于255，如何赋值给recordset

[bhguo]

大家好，
我程序后台用的是access数据库，采用Microsoft.Jet.OLEDB.4.0的方式连接数据库。select查询时，有一个字段的值是通过字符串拼接得到的，现发现，如果结果字符串的长度大于255，赋值给recordset后，结果是不对的，会被截断。

同样的select语句在access数据库中执行，返回的结果正常，说明select语句本身没问题。请问，长度大于255的字符串计算结果如何赋值给recordset，谢谢！

程序如下：

Dim Conn As New ADODB.Connection
Dim rst As New ADODB.Recordset
Dim strConn$, strSQL$, strExpression$

strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\try.mdb;Persist Security Info=False"
Conn.CursorLocation = adUseClient
Conn.Open strConn

'这里本应为字符串计算表达式，为了简化问题，我用固定字符串替代，总长度为554
strExpression = "'1,2,3,4,5,6,7,8,9,11,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,201,203,204,205,206'"

strSQL = "Select *," & strExpression & " as MayViewFields from SheetList"

With rst
.CursorType = adOpenStatic
.LockType = adLockOptimistic
.CursorLocation = adUseClient
.Open strSQL, Conn
End With

Debug.Print rst.Fields("MayViewFields")
'打印的字符串，只有255个字符：1,2,3,4,5,6,7,8,9,11,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,
'也就是说，总长度为554的字符串，通过sql select语句赋值给字段后，只剩下255个字符，其它被截断丢失

rst.Close
Conn.Close

[易登软件Access开发]

access最长只能是255

[风常度]

据说引号要转换。你这种情况，不如试试用数组来处理数据。

[xyxhz]

access最长只能是255，建议换一个数据类型，附件，可以解决问题

[zhu_terry]

什么样的查询会键入这么长的关键词？ 实际应用中我是没碰到过这样的需求。是不是可以尝试从源头去更改解决这个问题的思路，而不要局限于在数据库端。