SQL不会在Access和.Net中返回类似的数据

Question

仅供参考:使用VS 2010和Access 2010创建Windows桌面应用程序

在尝试查询和访问数据库时,我在VB.Net中遇到了一些奇怪的行为.我有一个SQL脚本,当在Access中运行时,会生成一个包含记录的数据集.但是,当我在VB.Net(连接到同一访问数据库)中运行相同的脚本时,查询不会产生任何结果.这是我的.Net脚本:

Dim strConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & item.Text
Dim conn As System.Data.OleDb.OleDbConnection
Dim da As OleDbDataAdapter
Dim s As String = " SELECT" & vbCrLf _ 
   & "  GrantData.[Grant Number]," & vbCrLf _
   & " OutputData.[Output], " & vbCrLf _
   & " OutputData.PlanNumber, " & vbCrLf _
   & " OutputData.ActualNumber" & vbCrLf _
   & " FROM " & vbCrLf _
   & " Themes, " & vbCrLf _
   & " GrantThemes, " & vbCrLf _
   & " GrantData," & vbCrLf _
   & " OutputData" & vbCrLf _
   & " WHERE" & vbCrLf _
   & " Themes.ThemeID = GrantThemes.ThemeId AND" & vbCrLf _
   & " GrantData.[Grant Number] = GrantThemes.[Grant Number] AND" & vbCrLf _
   & " GrantData.[Grant Number] =OutputData.[Grant Number] AND" & vbCrLf _
   & " ( " & vbCrLf _
   & " (GrantData.Status in ('Cleared', 'Completed', 'Closed')) AND" & vbCrLf _
   & " (Themes.Theme Like '*infrastructure*' or Themes.Theme Like '*construction*')" & vbCrLf _
   & " )" & vbCrLf _
   & " ORDER BY" & vbCrLf _
   & " GrantData.[Grant Number];"


conn = New System.Data.OleDb.OleDbConnection(strConnectionString)
conn.Open()
Try
   da = New OleDbDataAdapter(s, strConnectionString)
   da.Fill(ds, sqlStatement)   
Catch ex As Exception   

Finally
End Try

所以,就像我说的,如果我运行它,数据集是空的(我在ds上有一个断点,可以查看数据集).但是,如果我在SQL字符串上放置一个断点并将其复制到Access数据库中,它运行就好了.有人有什么建议吗？

Answer 1

Like外卡有问题.

虽然这适用于Access会话...

Themes.Theme Like '*infrastructure*' or Themes.Theme Like '*construction*'

您需要将其替换%为*与OleDb的...

Themes.Theme Like '%infrastructure%' or Themes.Theme Like '%construction%'

或者,如果您更喜欢一个查询,它会从OleDb中获得与Access相同的结果,请使用ALike而不是Like.

Themes.Theme ALike '%infrastructure%' or Themes.Theme ALike '%construction%'