ADODB.Recordset.RecordCount 问题。

wh3862881 2007-12-11 02:07:26

Public Function getLastCode(letter As String) As String
Dim rs As New ADODB.Recordset
Dim sqlstr As String

rs.CursorLocation = adUseClient
rs.CursorType = adOpenStatic
'sqlstr = "select top 1 * from equipment where code like '" & letter & "#####' order by code desc"
sqlstr = "select top 1 * from equipment where code like '" & letter & "*' order by code desc"
Set rs = cn.Execute(sqlstr)

If rs.RecordCount > 0 Then
getLastCode = rs(0).Value
Else
getLastCode = letter & "000000"
End If
End Function

本人刚一直研究C#，刚接触VB 对ADODB还不熟悉，
ask：上述代码，为何rs.RecordCount 始终为0，请达人指教

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neituib 2007-12-12

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我特别恨菜继明！

想找到更合适的工作，通过内部推荐更容易成功

内推网内部推荐求职快线

zuoxingyu 2007-12-12

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rs.CursorLocation = adUseClient
把游标类型改成客户端的，就可以了

白发程序猿 2007-12-11

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是0的话，肯定是SQL语句的问题，就按上面说的把*改成%试一下就好了

TimLee✿ 2007-12-11

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1. rs.CursorLocation = adUseClient
2. vb的sql语句通配符是 %和_

vbman2003 2007-12-11

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0是没有数据返回，是你SQL语法错误，在ACCESS环境中用通配符用*，VB中是通过jet引擎执行SQL语句，JET引擎只支持%通配符

wh3862881 2007-12-11

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If rs.EOF Then
getLastCode = letter & "000000"
Else
getLastCode = rs(0).Value
End If

用了这代码，但程序判断始终是EOF 无论数据库是否有记录。。

of123 2007-12-11

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或



  'Set rs = cn.Execute(sqlstr) 

  rs.Open sqlstr, cn

wh3862881 2007-12-11

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RecordCount是0还是-1？

RecordCount的值是0 是不-1
-1 是因为游标设置问题，这个我知道

of123 2007-12-11

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        If rs.EOF Then 

            getLastCode = letter & "000000"

        Else 

            getLastCode = rs(0).Value 

        End If

大王派我去巡山 2007-12-11

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RecordCount是0还是-1？

wh3862881 2007-12-11

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Set cn = New ADODB.Connection
cn.CursorLocation = adUseClient
cn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & App.Path & "\data\E0508.mdb;Persist Security Info=False;Jet OLEDB:Database Password=hwrj"
cn.Open

cn的设置代码。。

_码农一个_ 2007-12-11

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rs.CursorType = adOpenStatic 是对的
但是数据库连接cn 类型是否设置正确？

大王派我去巡山 2007-12-11

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Sorry，我发错了，没仔细看，原来是like语法的问题。

算我没说：）

wh3862881 2007-12-11

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sqlstr = "select top 1 * from equipment where code like '"& letter &"%' order by code desc

sqlstr = "select top 1 * from equipment where code like '"& letter &"*' order by code desc

我在ACCESS数据库中运行过，是可以查询到记录的·通用。
SQL语句无任何问题

大王派我去巡山 2007-12-11

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http://topic.csdn.net/u/20071206/12/24be2e04-1772-4148-8f67-ec6f91845d46.html

vbman2003 2007-12-11

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ACCESS数据库，VB中查询like语句中的“*”要改为"%"号







sqlstr = "select top 1 * from equipment where code like '"& letter &"%' order by code desc"

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