i'm trying to figure out what's wrong with my code,
I'm trying to extract the value of employe ID selected from a dropdown, then get all information of that employee and place it in a textbox vb.net form, but there's a error whenever i select an employee ID
it's giving me an error message of : "An unhandled exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll
Additional information: No value given for one or more required parameters."
Thus highlighting reader, i'm not sure what's the problem, i have initialized the reader... Please guide me. Thanks
Private Sub eNumText_SelectedIndexChanged(sender As Object, e As EventArgs) Handles eNumText.SelectedIndexChanged
Dim dbSource = "Data Source= C:\Databse\Company_db.accdb"
con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source= c:\Databse\Company_db.accdb"
Dim sqlQuery As String
Dim sqlCommand As New OleDbCommand
Dim sqlAdapter As New OleDbDataAdapter
Dim Table As New DataTable
Dim empNum As String
Dim empFname As String
Dim empLname As String
Dim empDept As String
Dim empStat As String
Dim empYears As String
empNum = eNumText.Text
empFname = empFnameText.Text
empLname = empLnameText.Text
empDept = DeptText.Text
empStat = StatText.Text
empYears = yearstext.Text
sqlQuery = "SELECT * FROM tbl_empinfo WHERE EmpID like empNum"
With sqlCommand
.CommandText = sqlQuery
.Connection = con
.Parameters.AddWithValue("EmpID", empNum)
With sqlAdapter
.SelectCommand = sqlCommand
.Fill(Table)
End With
With DataGridView1
.DataSource = Table
End With
End With
Dim path = "Data Source= C:\Databse\Company_db.accdb"
Dim command = "SELECT * FROM tbl_empinfo WHERE EmpID like empNum"
QueryData(path, Command)
con.Close()
End Sub
Private Sub QueryData(PathDb As String, command As String)
PathDb = "Data Source= C:\Databse\Company_db.accdb"
Using connection As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & PathDb)
Using da As New System.Data.OleDb.OleDbCommand(command, con)
con.Open()
Dim reader = da.ExecuteReader()
If reader.Read() Then
empFnameText.Text = reader("FirstName")
empLnameText.Text = reader("LastName")
End If
con.Close()
End Using
End Using
End Sub
You need to prefix your parameter empNum with an #: #empNum. See this answer: How to pass a parameter from vb.net for an example.
Related
Hey there are many question like this however i didn't find the right one. i keep on getting this error,
image
i am Using
vb.net and Ms-access database.
I have researched and didn't get anything, i checked the name "productID" and it is correct. So i dont know what wrong? Please help
My Code:
Private Sub btnAdd_Click(sender As Object, e As EventArgs) Handles btnAdd.Click
Dim dbProvider As String
Dim dbSource As String
Dim MyDocumentsFolder As String
Dim TheDatabase As String
Dim FullDatabasePath As String
Dim Sql As String
Dim con As New OleDb.OleDbConnection
Dim empty = Me.Controls.OfType(Of TextBox)().Where(Function(txt) txt.Text.Length = 0)
If empty.Any Then
MessageBox.Show("Please fill all informations")
Else
dbProvider = "PROVIDER=Microsoft.Jet.OLEDB.4.0;"
TheDatabase = "C:\Users\jacob\Desktop\MS Office\project.mdb"
MyDocumentsFolder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
FullDatabasePath = MyDocumentsFolder & TheDatabase
dbSource = "Data Source = " & TheDatabase
con.ConnectionString = dbProvider & dbSource
Sql = "INSERT INTO tblUsers (productID, quantity, price, productSection, supplierID) VALUES (#ProductID, #Quantity, #Price, #ProductSection, #SupplierID)"
MessageBox.Show("Database is now open")
con.Open()
Dim command As New OleDb.OleDbCommand(Sql, con)
command.Parameters.Add("#ProductID", OleDb.OleDbType.VarChar).Value = txtProductName.Text
command.Parameters.Add("#Quantity", OleDb.OleDbType.Integer).Value = txtQuantity.Text
command.Parameters.Add("#Price", OleDb.OleDbType.Currency).Value = txtPrice.Text
command.Parameters.Add("#ProductSection", OleDb.OleDbType.VarChar).Value = txtSection.Text
command.Parameters.Add("#SupplierID", OleDb.OleDbType.VarChar).Value = txtSupplier.Text
command.ExecuteNonQuery()
MessageBox.Show("Product Added Successfully")
con.Close()
MessageBox.Show("Database is now Closed")
End If
End Sub
The error is shown in this line : command.ExecuteNonQuery()
SQL is case sensitive, check if something is capitalized in your Sql variable and not capitalized in your table in SQL server or vise versa.
you can also check if the capitalization on the parameters might be causing the issue as well.
I am trying learn how to use Access within VB.NET so i tried to make a simple application using an Access Database that can be used as a dictionary where someone can add some words int the database and then he can search for them.
My db contains two tables one with Word | Description and another one with Word | Synonym
The issue is that one word may have more than one Synonyms so i was thinking i could type all the synonyms in a textbox and using Regex.Split(" ") to split them and insert them in a loop. Can this be done with OleDbParameters?
This is what i have done so far but it only inserts the last record:
str = "insert into Synonyms ([Word],[Synonym]) values (#word,#synonym)"
cmd = New OleDbCommand(str, myConnection)
cmd.Parameters.Add(New OleDbParameter("Word", CType(txtWord.Text,
String)))
cmd.Parameters.Add("#synonym", OleDbType.VarChar)
Dim syn As String() = Regex.Split(txtSynonyms.Text, " ")
Dim i As Integer = 0
While i < syn.Length()
cmd.Parameters("#synonym").Value = syn(i)
i = i + 1
End While
Try
cmd.ExecuteNonQuery()
cmd.Dispose()
MsgBox("Synonyms for word """ & txtWord.Text & """ added")
txtWord.Clear()
txtSynonyms.Clear()
Catch ex As Exception
MsgBox(ex.Message)
End Try
myConnection.Open()
While i < syn.Length()
cmd.Parameters("#synonym").Value = syn(i)
cmd.ExecuteNonQuery()
i = i + 1
End While
myConnection.Close()
Maybe you will find this helpful.
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Dim con As New OleDb.OleDbConnection
Dim dbprovider As String
Dim dbsource As String
Dim ds As New DataSet
Dim da As OleDb.OleDbDataAdapter
Dim sql As String
Dim inc As Integer
dbprovider = "Provider=Microsoft.ACE.OLEDB.12.0;"
dbsource = "Data Source = C:\your_path_here\Nwind_Sample.accdb"
con.ConnectionString = dbprovider & dbsource
con.Open()
sql = "SELECT * FROM [OrderDetails]"
da = New OleDb.OleDbDataAdapter(sql, con)
da.Fill(ds, "OrderDetails")
Dim builder As New OleDbCommandBuilder(da)
Dim dsnewrow As DataRow
dsnewrow = ds.Tables("OrderDetails").NewRow()
dsnewrow.Item(0) = OrderID.Text
dsnewrow.Item(1) = ProductID.Text
dsnewrow.Item(2) = UnitPrice.Text
dsnewrow.Item(3) = Quantity.Text
dsnewrow.Item(4) = Discount.Text
'dsnewrow.Item(6) = True
ds.Tables("OrderDetails").Rows.Add(dsnewrow)
da.Update(ds, "OrderDetails")
End Sub
End Class
I'm trying to update the records from textboxes into the Access database, I'm wondering every time I hit save, it generates an error
An unhandled exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll
Additional information: No value given for one or more required parameters.
Highlighting .ExecuteNonQuery()
What does it mean? It's preventing me to run my code :(
Private Sub SaveButton_Click(sender As Object, e As EventArgs) Handles SaveButton.Click
Dim empNum As String
Dim empFname As String
Dim empLname As String
Dim empDept As String
Dim empStat As String
Dim empYears As String
empNum = eNumText.Text
empFname = empFnameText.Text
empLname = empLnameText.Text
empDept = DeptText.Text
empStat = StatText.Text
empYears = yearstext.Text
con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source= c:\Databse\Company_db.accdb"
con.Open()
Dim SqlAdapter As New OleDbDataAdapter
Dim Table As New DataTable
Dim sqlQuery As String = "UPDATE tbl_empinfo " & _
"SET FirstName=empFname, LastName=empLname, Department=empDept, " & _
"Status=empStat, Years=empYears " & _
"WHERE empID=empNum"
Dim cmd As New OleDbCommand
With cmd
.CommandText = sqlQuery
.Connection = con
.Parameters.AddWithValue("FirstName", empFname)
.Parameters.AddWithValue("LastName", empLname)
.Parameters.AddWithValue("Department", empDept)
.Parameters.AddWithValue("Status", empStat)
.Parameters.AddWithValue("Years", empYears)
.ExecuteNonQuery()
End With
Using cmd2 = New OleDbCommand(sqlQuery, con)
cmd.Parameters.AddWithValue("FirstName", empFname)
cmd.Parameters.AddWithValue("LastName", empLname)
cmd.Parameters.AddWithValue("Department", empDept)
cmd.Parameters.AddWithValue("Status", empStat)
cmd.Parameters.AddWithValue("Years", empYears)
cmd.ExecuteNonQuery()
End Using
sqlQuery = "SELECT * FROM tbl_empinfo "
Dim cmd1 As New OleDbCommand
Dim da As New OleDbDataAdapter
With cmd1
.CommandText = sqlQuery
.Connection = con
With SqlAdapter
.SelectCommand = cmd1
.Fill(Table)
End With
With DataGridView1
.DataSource = Table
End With
End With
con.Close()
End Sub
You are trying to set an UPDATE command text for the SelectCommand of the Adapter. This, of course has no way to be successful. Last but not least the UPDATE command text doesn't contain a WHERE clause, and so, if executed, it updates every record in the table tbl_empinfo with the same data.
In this context there is no need to use an adapter. You could simply execute the command, providing an appropriate WHERE clause and the values for the other parameters
Dim sqlQuery As String = "UPDATE tbl_empinfo " & _
"SET FirstName=?, LastName=?, Department=?, " & _
"Status=?, Years=? " & _
"WHERE empID=?"
Dim cmd As New OleDbCommand
With cmd
.CommandText = sqlQuery
.Connection = con
.Parameters.AddWithValue("#p1", empFName)
.Parameters.AddWithValue("#p2", empLName)
.Parameters.AddWithValue("#p3", empDept)
.Parameters.AddWithValue("#p4", empStat)
.Parameters.AddWithValue("#p5", empYears)
.Parameters.AddWithValue("#p6", empNum)
.ExecuteNonQuery()
End With
After this you could call the code that reloads the data to fill your grid
sqlQuery = "SELECT * FROM tbl_empinfo"
Dim cmd1 As New OleDbCommand
Dim da As New OleDbDataAdapter
Dim Table As New DataTable
With cmd1
.CommandText = sqlQuery
.Connection = con
With da
.SelectCommand = cmd1
.Fill(Table)
End With
With DataGridView1
.DataSource = Table
End With
End With
Notice that I have changed the name of the command and the adapter to a less confusing names. SqlCommand And SqlDataAdapter are the names of the classes equivalent to the OleDbCommand and OleDbDataAdapter but used for Sql Server. At first sight I was thinking that you were trying to use the SqlClient classes to update an MS-Access database.
Hi guys I'm trying to search an employee information using SQL from MS Access, and hoping to put the fname lname and such details in their respective textbox which correspond to a specific employee's ID number. I have managed to make the SQL work but I don't know how to extract files from my sql statement and place it inside .text(text box), can you please guide me? Thanks
Here is my code so far:
(UPDATED my code) got an error message : Additional information: ExecuteReader: Connection property has not been initialized. Highlighting Reader below. How can i fix this? I'm trying to extract data and place it into the textbox? Thanks
Private Sub eNumText_SelectedIndexChanged(sender As Object, e As EventArgs) Handles eNumText.SelectedIndexChanged
Dim dbSource = "Data Source= C:\Databse\Company_db.accdb"
con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source= c:\Databse\Company_db.accdb"
Dim sqlQuery As String
Dim sqlCommand As New OleDbCommand
Dim sqlAdapter As New OleDbDataAdapter
Dim Table As New DataTable
Dim empNum As String
Dim empFname As String
Dim empLname As String
Dim empDept As String
Dim empStat As String
Dim empYears As String
empNum = eNumText.Text
empFname = empFnameText.Text
empLname = empLnameText.Text
empDept = DeptText.Text
empStat = StatText.Text
empYears = yearstext.Text
sqlQuery = "SELECT * FROM tbl_empinfo WHERE EmpID like empNum"
With sqlCommand
.CommandText = sqlQuery
.Connection = con
.Parameters.AddWithValue("EmpID", empNum)
With sqlAdapter
.SelectCommand = sqlCommand
.Fill(Table)
End With
With DataGridView1
.DataSource = Table
End With
End With
Dim path = "Data Source= C:\Databse\Company_db.accdb"
Dim command = "SELECT * FROM tbl_empinfo WHERE EmpID like empNum"
QueryData(path, command)
con.Close()
End Sub
Private Sub QueryData(PathDb As String, command As String)
Using connection As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & PathDb)
Using da As New System.Data.OleDb.OleDbCommand(command, connection)
connection.Open()
Dim reader = da.ExecuteReader()
If reader.Read() Then
empFnameText.Text = reader("fname")
empLnameText.Text = reader("lname")
End If
connection.Close()
End Using
End Using
End Sub
for this, you need only this classes: Connection, Command, Reader.
Other classes in the code in question, some are redundant and some are required but in complicated than a simple case presentation.
Private Sub QueryData(PathDb As String, command As String)
Using connection As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & PathDb)
Using com As New System.Data.OleDb.OleDbCommand(command, connection)
connection.Open()
Dim reader = com.ExecuteReader()
If reader.Read() Then
TextBox1.text = reader("fname")
TextBox2.text = reader("lname")
End If
connection.Close()
End Using
End Using
End Sub
call the method so:
Dim path = "C:\Databse\Company_db.accdb"
Dim command = "SELECT * FROM tbl_empinfo WHERE EmpID like empNum"
QueryData(path, command)
EDIT - Use parameters:
Private Sub QueryData(PathDb As String, command As String, id As String)
Using connection As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & PathDb)
Using com As New System.Data.OleDb.OleDbCommand(command, connection)
com.Parameters.AddWithValue("", id)
connection.Open()
Using reader = com.ExecuteReader()
If reader.Read() Then
TextBox1.Text = reader("fname")
TextBox2.Text = reader("lname")
End If
End Using
connection.Close()
End Using
End Using
End Sub
Call the method:
Dim path = "C:\Databse\Company_db.accdb"
Dim command = "SELECT * FROM tbl_empinfo WHERE EmpID = ?"
Dim empNum = "..."
QueryData(path, command, empNum)
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.