This is my code I have put behind my submit button, I have two text boxes Name and E-mail that I want to be added to my database that it does not work wonder if anyone can help
Dim Strnm As String = Request.Form("txtname")
Dim Strem As String = Request.Form("txtemail")
Dim objConnection As OleDbConnection = Nothing
Dim objcmd As OleDbCommand = Nothing
Dim StrSQL As String
Dim dbConn As OleDbConnection = Nothing
Dim filepath = "G:\WebSites\WebSite1\App_Data\register_log.ldf"
dbConn = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=G:\registration.accdb")
dbConn.Open()
StrSQL = "insert into tblregistration (Name, E-mail) values (?,?)"
objcmd = New OleDbCommand(StrSQL, dbConn)
objcmd.Parameters.Add(New System.Data.OleDb.OleDbParameter("#txtname", Strnm))
objcmd.Parameters.Add(New System.Data.OleDb.OleDbParameter("#txtemail", Strem))
'close connection
dbConn.Close()
Response.Write("submitted successfully")
You did not execute the query. Your code can be also be shortened with Using blocks which declare and dispose of things:
Dim Strnm As String = Request.Form("txtname")
Dim Strem As String = Request.Form("txtemail")
Dim StrSQL = "insert into tblregistration (Name, E-mail) values (?,?)"
Using dbConn = New OleDbConnection(connection string...),
objcmd = New OleDbCommand(StrSql, objConnection)
dbConn.Open()
objcmd.Parameters.Add(New System.Data.OleDb.OleDbParameter("#txtname", Strnm))
objcmd.Parameters.Add(New System.Data.OleDb.OleDbParameter("#txtemail", Strem))
objcmd.ExecuteNonQuery ' execute the query
End Using ' close and dispose of dbConn, objcmd
Response.Write("submitted successfully")
There are also 2 Connection objects declared (objConnection and dbConn) in the code.
Using acts like Dim in so far the code can declare and initialize things in one line of code. But mainly it assures that these things are closed and disposed of at the end of the block. The code also uses the constructor to pass the SQL and Connection to dbConn and objCmd when they are created. It only saves a line or two of code, but assumes that they have what they need from the moment they are created.
You can write also use a function to return a Connection object so that you do not have to have the connection string throughout your code. See this answer.
Related
I can select the data from an Access database, but I tried many ways to INSERT INTO database. There is no error message, but it didn't insert the data.
Code:
Dim conn As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & CurDir() & "\fsDB1.accdb")
Dim cmd As OleDbCommand
Dim dr As OleDbDataReader
conn.Open()
Dim CommandString As String = "INSERT INTO tblfile(stdUname,filePw,filePath,status) VALUES('" & userName & "','" & filePw & "','" & filePath & "','A')"
Dim command As New OleDbCommand(CommandString, conn)
Command.Connection = conn
Command.ExecuteNonQuery()
I just want a simple easy way to INSERT INTO an Access database. Is it possible because of the problem of Access database? I can insert this query by running query directly in Access.
Firstly I would check the database settings. If your app copies a new copy of the database each time you run it that would explain why you can select existing data and why your new data is not being saved (Well it is being saved, but the database keeps getting replaced with the old one). Rather set it up to COPY IF NEWER.
Further, you should ALWAYS use parameterized queries to protect your data. It is also is less error prone than string concatenated commands ans is much easier to debug.
Also, I recommend using a USING block to handle database connections so that your code automatically disposes of resources no longer needed, just in case you forget to dispose of your connection when you are done. Here is an example:
Using con As New OleDbConnection
con.ConnectionString = "Provider = Microsoft.ACE.OLEDB.12.0; " & _
"Data Source = "
Dim sql_insert As String = "INSERT INTO Tbl (Code) " & _
"VALUES " & _
"(#code);"
Dim sql_insert_entry As New OleDbCommand
con.Open()
With sql_insert_entry
.Parameters.AddWithValue("#code", txtCode.Text)
.CommandText = sql_insert
.Connection = con
.ExecuteNonQuery()
End With
con.Close()
End Using
Here is an example where data operations are in a separate class from form code.
Calling from a form
Dim ops As New Operations1
Dim newIdentifier As Integer = 0
If ops.AddNewRow("O'brien and company", "Jim O'brien", newIdentifier) Then
MessageBox.Show($"New Id for Jim {newIdentifier}")
End If
Back-end class where the new primary key is set for the last argument to AddNewRow which can be used if AddNewRow returns true.
Public Class Operations1
Private Builder As New OleDbConnectionStringBuilder With
{
.Provider = "Microsoft.ACE.OLEDB.12.0",
.DataSource = IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Database1.accdb")
}
Public Function AddNewRow(
ByVal CompanyName As String,
ByVal ContactName As String,
ByRef Identfier As Integer) As Boolean
Dim Success As Boolean = True
Dim Affected As Integer = 0
Try
Using cn As New OleDbConnection With {.ConnectionString = Builder.ConnectionString}
Using cmd As New OleDbCommand With {.Connection = cn}
cmd.CommandText = "INSERT INTO Customer (CompanyName,ContactName) VALUES (#CompanyName, #ContactName)"
cmd.Parameters.AddWithValue("#CompanyName", CompanyName)
cmd.Parameters.AddWithValue("#ContactName", ContactName)
cn.Open()
Affected = cmd.ExecuteNonQuery()
If Affected = 1 Then
cmd.CommandText = "Select ##Identity"
Identfier = CInt(cmd.ExecuteScalar)
Success = True
End If
End Using
End Using
Catch ex As Exception
Success = False
End Try
Return Success
End Function
End Class
I'm trying to pass this Update command to a database, it completes ok with no errors but it doesnt update the database and I can't understand why?
Dim Cmd As OleDbCommand
Dim SQL As String
Dim objCmd As New OleDbCommand
Dim Con = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & My.Settings.MasterPath)
Dim Item = "08/08/2015"
SQL = ("UPDATE [Hol Dates] SET [" & EmployeeList.Text & "]= #Htype WHERE [HDate]=#Hdate")
Cmd = New OleDbCommand(SQL, Con)
objCmd = New OleDbCommand(SQL, Con)
objCmd.Parameters.AddWithValue("#Hdate", item)
objCmd.Parameters.AddWithValue("#Htype", "None")
Con.Open()
Dim ans = MsgBox("Do you want to unbook this holiday?", MsgBoxStyle.YesNo)
If ans = MsgBoxResult.Yes Then
objCmd.ExecuteNonQuery()
Else
Exit Sub
End If
Con.Close()
Con.Dispose()
You need to reverse the order in which you add the parameters to the OleDbCommand object. OleDb allows us to assign names to parameters but it ignores the names and only pays attention to the order in which the parameters appear in the CommandText.
Therefore, since your SQL statement refers to Htype and then Hdate you need to add the parameters in that same order.
This is a new concept for me and I can't quite see what's causing the error
I'm attempting to populate a datagridview control from a single field in an Access database (from a combo and Text box source).
Using literals works, but not with the parameter.
Dim conn As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & Backend & ";Persist Security Info=False;")
Dim command As New OleDbCommand("Select Year from tblTest ", conn)
Dim criteria As New List(Of String)
If Not cboYear.Text = String.Empty Then
criteria.Add("Year = #Year")
command.Parameters.AddWithValue("#Year", cboYear.Text)
End If
If criteria.Count > 0 Then
command.CommandText &= " WHERE " & String.Join(" AND ", criteria)
End If
Dim UserQuery As New OleDbDataAdapter(command.CommandText, conn)
Dim UserRet As New DataTable
UserQuery.Fill(UserRet)
With frmDGV.DataGridView2
.DataSource = UserRet
End With
frmDGV.DataGridView2.Visible = True
frmDGV.Show()
Trying to Fill the datatable shows exception 'No value given for one or more required parameters.'
The value of command.CommandText at that point is "Select Year from tblTest WHERE Year = #Year"
Your instance of OleDbDataAdapter was created using two parameters query text and connection.
Dim UserQuery As New OleDbDataAdapter(command.CommandText, conn)
In this case DataAdapter doesn't know about parameters at all.
Instead use constructor with paremeter of type OleDbCommand.
Dim UserQuery As New OleDbDataAdapter(command)
In your code instance of OleDbCommand already associated with connection
Below code is supposed to update a table in oracle with rows imported. But it seems to update all columns in the table with only the first column which is imported from the CSV file. I figure its the "ReadFields" property which needs to manipulated/changed.. PLEASE offer me any suggestions, its urgent.
MsgBox("Saving...")
Dim parser As New FileIO.TextFieldParser("C:\Documents and Settings\test\Desktop\test.csv")
parser.Delimiters = New String() {","} ' fields are separated by comma
parser.HasFieldsEnclosedInQuotes = True
parser.TrimWhiteSpace = True
Dim i As Integer
For i = 0 To DataGridView1.ColumnCount - 1
**Dim CurrentField = parser.ReadFields()**
Dim sConnectionString As String = "Data Source=TEST;User ID=TEST;Password=TEST;"
Dim strSql As String = "INSERT INTO SHOP_MATERIAL_ALLOCT(ORDER_NO, LINE_ITEM_NO, CONTRACT, PART_NO, QTY_REQUIRED, QTY_PER_ASSEMBLY) VALUES (:ORDER_NO,:LINE_ITEM_NO,:CONTRACT,:PART_NO,:QTY_REQUIRED,:QTY_PER_ASSEMBLY)"
Using conn As New OracleClient.OracleConnection(sConnectionString)
Using cmd As New OracleClient.OracleCommand()
Dim adapter As New OracleDataAdapter
conn.Open()
cmd.Connection = conn
cmd.CommandText = strSql
cmd.Parameters.AddWithValue("ORDER_NO", CurrentField(i))
cmd.Parameters.AddWithValue("LINE_ITEM_NO", CurrentField(i))
cmd.Parameters.AddWithValue("CONTRACT", CurrentField(i))
cmd.Parameters.AddWithValue("PART_NO", CurrentField(i))
cmd.Parameters.AddWithValue("QTY_REQUIRED", CurrentField(i))
cmd.Parameters.AddWithValue("QTY_PER_ASSEMBLY", CurrentField(i))
cmd.CommandText = strSql
adapter.InsertCommand = New OracleCommand(strSql, conn)
adapter.UpdateCommand = cmd
'adapter.Update(table)
cmd.ExecuteNonQuery()
cmd.Connection.Close()
DataGridView1.DataSource = Nothing
End Using
End Using
Next
End Sub
The FileIO.TextFieldParser.ReadFields method parses all the fields in the input string and stores them in an array. In the case above, you should iterate over the individual values in the returned array, but you're always using CurrentField(i). Try using the following to replace the relevant lines above:
cmd.Parameters.AddWithValue("ORDER_NO", CurrentField(0))
cmd.Parameters.AddWithValue("LINE_ITEM_NO", CurrentField(1))
cmd.Parameters.AddWithValue("CONTRACT", CurrentField(2))
cmd.Parameters.AddWithValue("PART_NO", CurrentField(3))
cmd.Parameters.AddWithValue("QTY_REQUIRED", CurrentField(4))
cmd.Parameters.AddWithValue("QTY_PER_ASSEMBLY", CurrentField(5))
Share and enjoy.
I have a VB.Net app that should enable the user to import CSV file into the datagrid (which it does) and then update those rows to a table in Oracle.
Here is what I have so far but it doesn't seem to work neither throw an error.
Private Sub Update_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Update.Click
MsgBox("Saving...")
Dim table As New DataTable()
Dim BindingSource As New BindingSource()
BindingSource.DataSource = table
table.Columns.Add("ORDER_NO")
table.Columns.Add("LINE_ITEM_NO")
table.Columns.Add("CONTRACT")
table.Columns.Add("PART_NO")
table.Columns.Add("QTY_REQUIRED")
table.Columns.Add("QTY_PER_ASSEMBLY")
table.Columns.Add("RELEASE_NO")
table.Columns.Add("SEQUENCE_NO")
table.Columns.Add("ORDER_CODE")
table.Columns.Add("PART_OWNERSHIP")
Dim parser As New FileIO.TextFieldParser("C:\Documents and Settings\User\Desktop\solution.csv")
parser.Delimiters = New String() {","} ' fields are separated by comma
parser.HasFieldsEnclosedInQuotes = True
parser.TrimWhiteSpace = True
parser.ReadLine()
Dim sConnectionString As String = "Data
Source=MYSERVER.COM;User ID=MYNAME;Password=MYPASSWD;"
Dim strSql As String = "INSERT INTO SHOP_MATERIAL_ALLOC_TAB(ORDER_NO,
LINE_ITEM_NO, CONTRACT, PART_NO, QTY_REQUIRED, QTY_PER_ASSEMBLY,
RELEASE_NO,SEQUENCE_NO,ORDER_CODE,PART_OWNERSHIP) VALUES (#ORDER_NO,
#LINE_ITEM_NO,#CONTRACT,#PART_NO,#QTY_REQUIRED,#QTY_PER_ASSEMBLY,#RELEASE_NO,#SEQUENCE_NO,#ORDER_CODE,#PART_OWNERSHIP)"
Using conn As New OracleClient.OracleConnection(sConnectionString)
Dim adapter As New OracleDataAdapter
Dim cmd As New OracleClient.OracleCommand()
cmd.Connection = conn
cmd.Connection.Open()
cmd.CommandText = strSql
adapter.InsertCommand = New OracleCommand(strSql, conn)
adapter.UpdateCommand = cmd
adapter.Update(table)
'--cmd.ExecuteReader()
cmd.Connection.Close()
MsgBox("Saved! Kindly check your Shop order!")
DataGridView1.DataSource = Nothing
End Using
End Sub
Now I have brought it down to inserting records in the table, but problem is it only parses the first column in the row.
So all suppose 6 columns in the table are updated with values from the first field in the CSV.
MsgBox("Saving...")
Dim parser As New FileIO.TextFieldParser("C:\Documents and Settings\nUser\Desktop\solution.csv")
parser.Delimiters = New String() {","} ' fields are separated by comma
parser.HasFieldsEnclosedInQuotes = True
parser.TrimWhiteSpace = True
Dim i As Integer
For i = 0 To DataGridView1.RowCount - 1
Dim CurrentField = parser.ReadFields()
'--parser.ReadLine()
Dim sConnectionString As String = "Data Source=MYSERVER.COM;User ID=MYUSER;Password=MYPASSWD;"
Dim strSql As String = "INSERT INTO SHOP_MATERIAL_ALLOCT(ORDER_NO, LINE_ITEM_NO, CONTRACT, PART_NO, QTY_REQUIRED, QTY_PER_ASSEMBLY) VALUES (:ORDER_NO, :LINE_ITEM_NO,:CONTRACT,:PART_NO,:QTY_REQUIRED,:QTY_PER_ASSEMBLY)"
Using conn As New OracleClient.OracleConnection(sConnectionString)
Using cmd As New OracleClient.OracleCommand()
Dim adapter As New OracleDataAdapter
conn.Open()
cmd.Connection = conn
cmd.CommandText = strSql
cmd.Parameters.AddWithValue("ORDER_NO", CurrentField(i))
cmd.Parameters.AddWithValue("LINE_ITEM_NO", CurrentField(i))
cmd.Parameters.AddWithValue("CONTRACT", CurrentField(i))
cmd.Parameters.AddWithValue("PART_NO", CurrentField(i))
cmd.Parameters.AddWithValue("QTY_REQUIRED", CurrentField(i))
cmd.Parameters.AddWithValue("QTY_PER_ASSEMBLY", CurrentField(i))
cmd.CommandText = strSql
adapter.InsertCommand = New OracleCommand(strSql, conn)
adapter.UpdateCommand = cmd
'adapter.Update(table)
cmd.ExecuteNonQuery()
cmd.Connection.Close()
DataGridView1.DataSource = Nothing
End Using
End Using
Next
Never used oracle so please ignore me if I'm being stupid.
Have you tried conn.Connect() rather than cmd.Connection.Open()?
I don't understand the part of your code that create a DataTable and add columns.
It's not used anywhere, so is not related to your issue.
Let's look at code relating data connection
' If I remember well, the parameters in an oracle statement are prefixed by a ":"
Dim strSql As String = "INSERT INTO SHOP_MATERIAL_ALLOC_TAB(ORDER_NO," +
"LINE_ITEM_NO, CONTRACT, PART_NO, QTY_REQUIRED, QTY_PER_ASSEMBLY, " +
"RELEASE_NO,SEQUENCE_NO,ORDER_CODE,PART_OWNERSHIP) VALUES (:ORDER_NO, " +
":LINE_ITEM_NO,:CONTRACT,:PART_NO,:QTY_REQUIRED,:QTY_PER_ASSEMBLY, " +
":RELEASE_NO,:SEQUENCE_NO,:ORDER_CODE,:PART_OWNERSHIP)"
' Connection and Command are Disposable, so use `Using` around them
Using conn As New OracleClient.OracleConnection(sConnectionString)
Using cmd As New OracleClient.OracleCommand()
Dim adapter As New OracleDataAdapter
conn.Open()
cmd.Connection = conn
cmd.CommandText = strSql
' Now you need to add the parameters to your command
' One parameter for each column used in the insert statement
' I suppose that values for the paramenter are in the current line from your CSV
cmd.Parameters.Add("ORDER_NO", OracleType.VarChar).Value = parser[index_of_orderNumber_Text])
' .... other parameters to be added....
' Now you can execute the INSERT statement directly with your command
cmd.ExecuteNonQuery()
End Using
And, as last thing, the OracleClient namespace has been deprecated by Microsoft, so you should try to replace with ODP directly from Oracle.