参数来自 vb.net 的 postgreSQL 查询
postgreSQL query with parameter from vb.net
我正在尝试编写一个 select 语句 (postgreSQL)，它使用我的应用程序屏幕中的一个字段。
我已经2天没成功了。
任何帮助 and/or 解释等...将不胜感激。
下面是整个子。 （代码尚未完成、优化或测试，因此请原谅任何错误的编码）
在以下行收到错误：ODBCdaDups.Fill(dsDups2)
收到的错误是：ERROR [42883] ERROR: operator does not exist: @text; & vblf & "Error while executing the query"
我尝试使用编号参数（$1、$2 等...），但也无法弄清楚。
Private Sub Check4Duplicate()
Dim DupMessage As String
Try
Dim DupSQL As String = Nothing
Dim DupConn As New OdbcConnection()
Dim strConn As String = ""
If GlobalVariables.logProd = 1 Then
strConn = "Driver={PostgreSQL ANSI};database=SacredSelections;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
Else
strConn = "Driver={PostgreSQL ANSI};database=SacredSelectionsTest;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
End If
Dim dsDups2 As New DataSet
Dim ODBCdaDups As OdbcDataAdapter
Dim cmdbldDups As OdbcCommandBuilder
Dim cmdDups As OdbcCommand
DupConn = New OdbcConnection(strConn)
DupConn.Open()
dsDups2 = New DataSet
ODBCdaDups = New OdbcDataAdapter
cmdbldDups = New OdbcCommandBuilder(ODBCdaDups)
dsDups2.DataSetName = "auctions"
' Create the SelectCommand.
' Original SQL Server command
'cmdDups = New OdbcCommand("Select * From auctions where auction_name = @auction_name;", DupConn)
' Trying to create new postgresql command
cmdDups = New OdbcCommand("do $$
begin
select *
from auctions
where auction_name = @auction_name;
end;
$$
", DupConn)
cmdDups.Parameters.Add("auction_name", SqlDbType.Text).Value = txt_auction_name.Text
cmdDups.Prepare()
ODBCdaDups.SelectCommand = cmdDups
ODBCdaDups.Fill(dsDups2)
DupConn.Close()
If Not DupConn Is Nothing Then DupConn.Dispose()
DupMessage = ""
' Loop over tables in the DataSet.
Dim collection As DataTableCollection = dsDups2.Tables
If dsDups2.Tables(0).Rows.Count = 0 Then
DupTitle = "Unique Record - Save Allowed"
If strEditType = "Edit" Then
DupMessage = "This will save changes to an existing Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
Else
DupMessage = "This will create a Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
End If
Else
DupTitle = "Duplicate Record - Save NOT Allowed"
DupMessage = "A record already exists with Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
MessageBox.Show(DupMessage, DupTitle)
End If
Catch ex As Exception
DupTitle = "Connection failed"
DupMessage = "Unable to Open Auction Information Connection to check for Existing Records"
MessageBox.Show(DupMessage, DupTitle)
End Try
End Sub
ODBC 中的参数名称无关紧要。重要的是参数在 sql 命令中出现的顺序必须与它们添加到 ParametersCollection.
的顺序相匹配
Using...End Using 即使出现错误也会阻止关闭和处置数据库对象。
我不得不猜测字段名称和数据类型，因此请检查您的数据库以获取实际值并相应地调整您的代码。如果任何字段是数字类型，您将不会将文本框的 .Text 属性 转换为正确的类型。
通常主键字段永远不会更新，因此从代码中删除主键字段的更新。如果字段自动递增，则不会为该字段插入值。通过删除自动编号字段中的任何插入来调整代码。
Private Function GetConnectionString() As String
Dim strConn As String
If GlobalVariables.logProd = 1 Then
strConn = "Driver={PostgreSQL ANSI};database=SacredSelections;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
Else
strConn = "Driver={PostgreSQL ANSI};database=SacredSelectionsTest;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
End If
Return strConn
End Function
Private Sub Check4Duplicate(strEditType As String)
Dim DupMessage As String
Dim DupTitle As String
Try
Dim dt As New DataTable
Using DupConn As New OdbcConnection(GetConnectionString())
Using cmdDups As New OdbcCommand("select auction_name from auctions where auction_name = ?;", DupConn)
cmdDups.Parameters.Add("@auction_name", OdbcType.VarChar).Value = txt_auction_name.Text
dt.Load(cmdDups.ExecuteReader)
End Using
End Using
If dt.Rows.Count = 0 Then
DupTitle = "Unique Record - Save Allowed"
If strEditType = "Edit" Then
DupMessage = "This will save changes to an existing Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
UpdateAuction()
Else
DupMessage = "This will create a Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
InsertAuction()
End If
Else
DupTitle = "Duplicate Record - Save NOT Allowed"
DupMessage = $"A record already exists with Auction ID {txt_auction_id.Text} and Auction Name {txt_auction_name.Text} and Location Name {txt_location_address.Text}"
MessageBox.Show(DupMessage, DupTitle)
End If
Catch ex As Exception
DupTitle = "Connection failed"
DupMessage = "Unable to Open Auction Information Connection to check for Existing Records"
MessageBox.Show(DupMessage, DupTitle)
End Try
End Sub
Private Sub InsertAuction()
Using DupConn As New OdbcConnection(GetConnectionString())
Using cmd As New OdbcCommand("Insert Into auctions (auction_id, auction_name, auction_address) Values (?,?,?)")
cmd.Parameters.Add("id", OdbcType.VarChar).Value = txt_auction_id.Text
cmd.Parameters.Add("name", OdbcType.VarChar).Value = txt_auction_name.Text
cmd.Parameters.Add("address", OdbcType.VarChar).Value = txt_location_address.Text
DupConn.Open()
cmd.ExecuteNonQuery()
End Using
End Using
End Sub
Private Sub UpdateAuction()
Using DupConn As New OdbcConnection(GetConnectionString())
Using cmd As New OdbcCommand("Update auctions Set auction_id = ?, auction_name = ?, auction_address = ? Where aution_name = ?")
cmd.Parameters.Add("id", OdbcType.VarChar).Value = txt_auction_id.Text
cmd.Parameters.Add("name", OdbcType.VarChar).Value = txt_auction_name.Text
cmd.Parameters.Add("address", OdbcType.VarChar).Value = txt_location_address.Text
cmd.Parameters.Add("name2", OdbcType.VarChar).Value = txt_auction_name.Text
DupConn.Open()
cmd.ExecuteNonQuery()
End Using
End Using
End Sub
这看起来像是代码重复，重复连接和命令的构造，但将这些项目保留在使用它们的方法中可以让我们确保它们已关闭和处置。
我正在尝试编写一个 select 语句 (postgreSQL)，它使用我的应用程序屏幕中的一个字段。
我已经2天没成功了。 任何帮助 and/or 解释等...将不胜感激。
下面是整个子。 （代码尚未完成、优化或测试，因此请原谅任何错误的编码） 在以下行收到错误：ODBCdaDups.Fill(dsDups2) 收到的错误是：ERROR [42883] ERROR: operator does not exist: @text; & vblf & "Error while executing the query" 我尝试使用编号参数（$1、$2 等...），但也无法弄清楚。
Private Sub Check4Duplicate()
Dim DupMessage As String
Try
Dim DupSQL As String = Nothing
Dim DupConn As New OdbcConnection()
Dim strConn As String = ""
If GlobalVariables.logProd = 1 Then
strConn = "Driver={PostgreSQL ANSI};database=SacredSelections;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
Else
strConn = "Driver={PostgreSQL ANSI};database=SacredSelectionsTest;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
End If
Dim dsDups2 As New DataSet
Dim ODBCdaDups As OdbcDataAdapter
Dim cmdbldDups As OdbcCommandBuilder
Dim cmdDups As OdbcCommand
DupConn = New OdbcConnection(strConn)
DupConn.Open()
dsDups2 = New DataSet
ODBCdaDups = New OdbcDataAdapter
cmdbldDups = New OdbcCommandBuilder(ODBCdaDups)
dsDups2.DataSetName = "auctions"
' Create the SelectCommand.
' Original SQL Server command
'cmdDups = New OdbcCommand("Select * From auctions where auction_name = @auction_name;", DupConn)
' Trying to create new postgresql command
cmdDups = New OdbcCommand("do $$
begin
select *
from auctions
where auction_name = @auction_name;
end;
$$
", DupConn)
cmdDups.Parameters.Add("auction_name", SqlDbType.Text).Value = txt_auction_name.Text
cmdDups.Prepare()
ODBCdaDups.SelectCommand = cmdDups
ODBCdaDups.Fill(dsDups2)
DupConn.Close()
If Not DupConn Is Nothing Then DupConn.Dispose()
DupMessage = ""
' Loop over tables in the DataSet.
Dim collection As DataTableCollection = dsDups2.Tables
If dsDups2.Tables(0).Rows.Count = 0 Then
DupTitle = "Unique Record - Save Allowed"
If strEditType = "Edit" Then
DupMessage = "This will save changes to an existing Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
Else
DupMessage = "This will create a Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
End If
Else
DupTitle = "Duplicate Record - Save NOT Allowed"
DupMessage = "A record already exists with Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
MessageBox.Show(DupMessage, DupTitle)
End If
Catch ex As Exception
DupTitle = "Connection failed"
DupMessage = "Unable to Open Auction Information Connection to check for Existing Records"
MessageBox.Show(DupMessage, DupTitle)
End Try
End Sub
ODBC 中的参数名称无关紧要。重要的是参数在 sql 命令中出现的顺序必须与它们添加到 ParametersCollection.
Using...End Using 即使出现错误也会阻止关闭和处置数据库对象。
我不得不猜测字段名称和数据类型，因此请检查您的数据库以获取实际值并相应地调整您的代码。如果任何字段是数字类型，您将不会将文本框的 .Text 属性 转换为正确的类型。
通常主键字段永远不会更新，因此从代码中删除主键字段的更新。如果字段自动递增，则不会为该字段插入值。通过删除自动编号字段中的任何插入来调整代码。
Private Function GetConnectionString() As String
Dim strConn As String
If GlobalVariables.logProd = 1 Then
strConn = "Driver={PostgreSQL ANSI};database=SacredSelections;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
Else
strConn = "Driver={PostgreSQL ANSI};database=SacredSelectionsTest;server=127.0.0.1;port=5432;uid=SSApp;sslmode=disable;readonly=0;protocol=7.4;User ID=SSApp;password=Cordova123;"
End If
Return strConn
End Function
Private Sub Check4Duplicate(strEditType As String)
Dim DupMessage As String
Dim DupTitle As String
Try
Dim dt As New DataTable
Using DupConn As New OdbcConnection(GetConnectionString())
Using cmdDups As New OdbcCommand("select auction_name from auctions where auction_name = ?;", DupConn)
cmdDups.Parameters.Add("@auction_name", OdbcType.VarChar).Value = txt_auction_name.Text
dt.Load(cmdDups.ExecuteReader)
End Using
End Using
If dt.Rows.Count = 0 Then
DupTitle = "Unique Record - Save Allowed"
If strEditType = "Edit" Then
DupMessage = "This will save changes to an existing Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
UpdateAuction()
Else
DupMessage = "This will create a Unique record for Auction ID " + txt_auction_id.Text + " and Auction Name " + txt_auction_name.Text + " and Location Name " + txt_location_address.Text
InsertAuction()
End If
Else
DupTitle = "Duplicate Record - Save NOT Allowed"
DupMessage = $"A record already exists with Auction ID {txt_auction_id.Text} and Auction Name {txt_auction_name.Text} and Location Name {txt_location_address.Text}"
MessageBox.Show(DupMessage, DupTitle)
End If
Catch ex As Exception
DupTitle = "Connection failed"
DupMessage = "Unable to Open Auction Information Connection to check for Existing Records"
MessageBox.Show(DupMessage, DupTitle)
End Try
End Sub
Private Sub InsertAuction()
Using DupConn As New OdbcConnection(GetConnectionString())
Using cmd As New OdbcCommand("Insert Into auctions (auction_id, auction_name, auction_address) Values (?,?,?)")
cmd.Parameters.Add("id", OdbcType.VarChar).Value = txt_auction_id.Text
cmd.Parameters.Add("name", OdbcType.VarChar).Value = txt_auction_name.Text
cmd.Parameters.Add("address", OdbcType.VarChar).Value = txt_location_address.Text
DupConn.Open()
cmd.ExecuteNonQuery()
End Using
End Using
End Sub
Private Sub UpdateAuction()
Using DupConn As New OdbcConnection(GetConnectionString())
Using cmd As New OdbcCommand("Update auctions Set auction_id = ?, auction_name = ?, auction_address = ? Where aution_name = ?")
cmd.Parameters.Add("id", OdbcType.VarChar).Value = txt_auction_id.Text
cmd.Parameters.Add("name", OdbcType.VarChar).Value = txt_auction_name.Text
cmd.Parameters.Add("address", OdbcType.VarChar).Value = txt_location_address.Text
cmd.Parameters.Add("name2", OdbcType.VarChar).Value = txt_auction_name.Text
DupConn.Open()
cmd.ExecuteNonQuery()
End Using
End Using
End Sub
这看起来像是代码重复，重复连接和命令的构造，但将这些项目保留在使用它们的方法中可以让我们确保它们已关闭和处置。