What's wrong in here, I always get some nasty errors even if the same code that I used earlier works. But when I apply it to other form it gives me the error above.
here's my code:
Imports System.Data.OleDb
Public Class Updater2
Public adminID As String
Public adminName As String
Public adminPass As String
Private con As New OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\db1.mdb;Jet OLEDB:Database Password=nrew123$%^;")
Private com As OleDb.OleDbCommand
Public Sub New()
con.Open()
com = New OleDb.OleDbCommand("Select * from admintable")
com.Connection = con
End Sub
Public Sub updates()
com.CommandText = "UPDATE admintable SET AdminName = '" & adminName & "', AdminPassS = '" & adminPass & "' WHERE ID = '" & adminID & "'"
com.ExecuteNonQuery()
End Sub
End Class
And here's the code in the button which tries to update the data:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
shikai.adminID = textbox1.text
shikai.adminName = TextBox4.Text
shikai.adminPass = TextBox3.Text
shikai.updates()
MsgBox("Successfully updated!")
End Sub
what might be wrong here?
A good trick for dealing with a no value given for one or more required parameters error when developing for an Access back end is to grab the content of the CommandText and paste it into a dummy query in Access itself. Then Access will offer you a popup identifying which field is causing the problem (usually a typo, as in your case).
The usual reason for this error is a missing or misspelled value. It seems likely that adminName is Null or a zero-length string.
When pasting the command text into access itself and Access pops up telling you which field is the problem, if there does not appear to be a type, try enclosing the field name in square brackets. [ ] It is possible that one of your columns may contain a keyword. This happened to me, which the column LL_ID - I had to change it to [LL_ID].
SELECT pt.person_name,pt.obile_no,pt.address_info FROM person_table pt LEFT JOIN company_table ct ON pt.com_id=ct.com_id WHERE pt.com_id=14
I used it for access database then this type of erro "no value given for one or more required parameters" happened.
I actually did typo error like pt.obile, but it will be pt.mobile. When i corrected this was working well.
For my side, there is a field I have used in my query but not in my access db. After adding that field in ms access db, it works. May be you also need to check well if the field you have in query are the same as in your db
Related
This is gonna be somewhat tricky to explain but I'll try to break it down. Note that this is created using VB.Net 2003.
I have a Web page which requires user to input data to save into SQL. They are required to fill in:
Course: {Select via drop-down table} \\ Variable name = Crse
Emp No: {Manually type the number} \\ Variable name = Emp
For the drop down list for Course, the data is obtained from an SQL table 'Course', with the columns:
| Course Code | Course Title |
Once input complete, I can then save the entry into my Emp_Course table in SQL using the query:
Dim updateState As String = "insert into EMP_COURSE" _
& "(Employee_No, CourseCode)" _
& "values('" & Emp.Text & "', " _
& "'"Crse.SelectedItem.ToString & "')"
Previously the drop-down list only needed the show Course Code, but now I'm required to add in the Course Title as well. Another thing to point out is that the Course Code has no fixed length.
Drop-down list sample:
Before:
A001
BX003
After:
A001 - Course A
BX003 - Course BX
Meaning I have to change the logic in populating the drop-down list:
Dim list As New SqlCommand("select CourseCode + ' - ' " _
& "+ CourseTitle as Course from [SQL].[dbo].[Course] " _
& "order by CourseCode", SQLDB)
Now comes my main issue, when I want to save my entry, the program obviously gives an error because the SQL still refers to the Course Code only, while my drop-down list is a Code + Description hybrid.
So since now I've made my course selection, how am I supposed to add to my SQL to update Emp_Course table to tell it to select the Course Code part of my hybrid selection?
I would just go to the Course table and just add a new Code + Title column and refer to that, but I have no authority to modify it and need to work around it.
Any other alternatives I can use?
Dim arr As String() = Crse.SelectedItem.ToString().Split(New Char() {"-"c})
Dim courseCode AS String = Trim(arr(0))
Dim updateState As String = "insert into EMP_COURSE" _
& "(Employee_No, CourseCode)" _
& "values('" & Emp.Text & "', " _
& "'"courseCode & "')"
Comments and explanations in line.
Imports System.Data.SqlClient
Public Class WebForm1
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
Crse.DataSource = CreateDataSource()
'Course is the concatenated string returned from
'the database containing the CourseCode and the CourseTitle
Crse.DataTextField = "Course"
Crse.DataValueField = "CourseCode"
Crse.DataBind()
Crse.SelectedIndex = 0
End If
End Sub
Protected Function CreateDataSource() As DataTable
Dim dt As New DataTable
Using SQLDB As New SqlConnection("Your connection string")
'This selects the CourseCode as a separate column and the string called Course
'containing the CourseCode and the CourseTitle
Using cmd As New SqlCommand("select CourseCode, CourseCode + ' - ' + CourseTitle as Course from [SQL].[dbo].[Course] order by CourseCode", SQLDB)
SQLDB.Open()
dt.Load(cmd.ExecuteReader)
End Using
End Using
Return dt
End Function
Protected Sub UpdateDatabase()
Using SQLDB As New SqlConnection("Your connection string")
Using cmd As New SqlCommand("insert into EMP_COURSE (Employee_No, CourseCode) values(#EmpNo, #CourseCode);", SQLDB)
'I guessed at the SqlDbType. Check the database for the real data types.
cmd.Parameters.Add("EmpNo", SqlDbType.Int).Value = CInt(Emp.Text)
'Always use parameters to prevent SQL injection
'The SelectedValue will return the CourseCode
cmd.Parameters.Add("#CourseCode", SqlDbType.VarChar).Value = Crse.SelectedValue
SQLDB.Open()
cmd.ExecuteNonQuery()
End Using
End Using
End Sub
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
UpdateDatabase()
End Sub
End Class
Split the value and get the course code as in the following code. Hope it helps.
Dim Str = Crse.SelectedItem.ToString
Dim strArr() As String
strArr = Str.Split(CType("-", Char()))
Dim CourseCode As String = strArr(0).Trim
I have this code to search in Access db with visual studio to search in SerialNumber column:
Private Sub TextBox2_TextChanged(sender As Object, e As EventArgs) Handles TextBox2.TextChanged
if Trim(TextBox2.Text) = "" Then
SpringDataBindingSource.Filter = ""
Else
SpringDataBindingSource.Filter = "SerialNumber = '" + TextBox2.Text + "'"
End If
End Sub
What if I want to search also in "Name" column with the same changed textbox?
Data Type in serialnumber column is number and in Name text.
The remarks in the BindingSource.Filter Property documentation state
To form a filter value, specify the name of a column followed by an operator and a value to filter on. The accepted filter syntax depends on the underlying data source. If the underlying data source is a DataSet, DataTable, or DataView, you can specify Boolean expressions using the syntax documented for the DataColumn.Expression property.
So, assuming the above condition is met and looking at the documented syntax:
SpringDataBindingSource.Filter = String.Format("SerialNumber = '{0}' OR Name = '{0}'", TextBox2.Text)
You might want to replace any single quotes in TextBox2.Text with two single quotes to escape them.
Thanks for all here to help me and gave me Ideas.
The solution I got it and did it is first I converted the serialnumber column data type from number to short text in MS Access DB then I used this code:
SpringDataBindingSource.Filter = "SerialNumber LIKE '%" & TextBox1.Text & "%'" & " OR Name LIKE '%" & TextBox1.Text & "%'"
Again Thank you for all :)
So this is the code that I am using:
Public Class Form1
Dim dtmSystemDate As Date
Dim strResult As String
Dim Student As Double = Nothing
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnBeginWorkout.Click
Dim cnn As New OleDb.OleDbConnection
Dim cmd As New OleDb.OleDbCommand
Dim Start As String = "Start"
' Set date/time to today's date/time.
dtmSystemDate = Now()
' Convert txtIDNumber to a Double.
Try
Student = CDbl(txtIDNumber.Text)
Catch ex As Exception
End Try
' Determine if input is a valid ID number.
If Student >= 10000 And Student <= 99999 Then
MessageBox.Show("Your start time is " & dtmSystemDate.ToString("F"), "Welcome, Student # " & Student.ToString())
Else
MessageBox.Show("Please enter a valid College ID number", "Invalid Entry", MessageBoxButtons.OK, MessageBoxIcon.Exclamation
)
End If
cnn.ConnectionString = "provider = microsoft.jet.oledb.4.0; data source = C:\users\econnelly\My Documents\Access Databases\Fit Track.mdb"
cnn.Open()
cmd.Connection = cnn
cmd.CommandText = "insert into Fit Track (Student_ID,Start/Stop,Date/Time) values ('" & Student & "','" & Start & "', '" & dtmSystemDate & "')"
cmd.ExecuteNonQuery()
cnn.Close()
I am attempting to pass these defined variables to an Access Database and so far have been unsuccessful.
Whenever I try to run my program, I get the following error:
An unhandled exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll
This error is triggering from the cmd.ExecuteNonQuery() function though I am not sure why.
As of yet, I have been unable to get the information to populate into the database at all. Can anyone point me in the right direction as to how to address this issue?
I believe the problem is with the table name "Fit Track" that has a space in it.
You could use square brackets like [Fit Track]
or you could use single quotes like 'Fit Track'
I don't know the answer, but I've ran into trouble when using spaces or special characters, like slashes, in database Table or Column names. Also, I think your connection string is incorrect. You might also want to read a little bit about SQL injection, it can be dangerous.
EDIT: You might also need to import System.Data.Oledb
I'm a novice with my coding so forgive me if my question seems basic but I'm having some trouble extracting my variables from this While Loop in order to then use the results of my SQL query for validation.
This script below is the event handling for a login button on an .aspx form processing an email and login field that will be listed in a correlating MSSQL database:
Public Class _Default
Inherits System.Web.UI.Page
Protected Sub submit_Click(sender As Object, e As EventArgs) Handles submit.Click
Dim Column1 As String
Dim Column2 As String
Dim SQL = "SELECT * FROM Logins WHERE Email='" & email.Text & "' AND Password='" & password.Text & "'"
Dim oSqlDataReader As System.Data.SqlClient.SqlDataReader = Nothing
Using oSqlConnection As New System.Data.SqlClient.SqlConnection("SERVER=[Server Name];UID=[User];PWD=[Pass];DATABASE=[Database Name]")
oSqlConnection.Open()
Using oSqlCommand As New System.Data.SqlClient.SqlCommand(SQL, oSqlConnection)
oSqlDataReader = oSqlCommand.ExecuteReader
While oSqlDataReader.Read
Column1 = oSqlDataReader(name:="Email")
Column2 = oSqlDataReader(name:="Password")
End While
End Using
oSqlConnection.Close()
End Using
If "Column 1 etc."
End if
End Sub
End Class
As far as I can tell my code is working with no errors but every time I try and create an If statement my Variable Column 1 and Column 2 are undeclared making them useless.
If anyone could help with the correct layout for my code or missing areas and an explanation as to where I've gone wrong that'd be great.
If you move the If block inside the loop, do you get closer to the behaviour that you're expecting?
Protected Sub submit_Click(sender As Object, e As EventArgs) Handles submit.Click
Dim Column1 As String
Dim Column2 As String
Dim SQL = "SELECT * FROM Logins WHERE Email='" & email.Text & "' AND Password='" & password.Text & "'"
Dim oSqlDataReader As System.Data.SqlClient.SqlDataReader = Nothing
Using oSqlConnection As New System.Data.SqlClient.SqlConnection("SERVER=[Server Name];UID=[User];PWD=[Pass];DATABASE=[Database Name]")
oSqlConnection.Open()
Using oSqlCommand As New System.Data.SqlClient.SqlCommand(SQL, oSqlConnection)
oSqlDataReader = oSqlCommand.ExecuteReader
While oSqlDataReader.Read
Column1 = oSqlDataReader(name:="Email")
Column2 = oSqlDataReader(name:="Password")
If "Column 1 etc....."
End if
End While
End Using
oSqlConnection.Close()
End Using
End Sub
It could be that your query is returning no rows or that the values returned are dbNull or nothing. I would check the data getting returned and error if appropriate.
Try running the query against the database directly. Are you getting a row back?
To avoid the error, you can declare the string as String.empty
Dim Column1 As String = String.empty
Or, when using it in the if statement check for nothing:
If Column1 Is Not Nothing AndAlso ...
Do not use string concatenation to build your sql query. Instead use sql-parameters to prevent sql injection and other issues.
I must admit that i don't know this syntax: oSqlDataReader(name:="Email"). Use following:
Dim email As String
Dim password As String
Dim sql = "SELECT * FROM Logins WHERE Email=#Email AND Password=#Password"
Using oSqlConnection As New System.Data.SqlClient.SqlConnection("SERVER=[Server Name];UID=[User];PWD=[Pass];DATABASE=[Database Name]")
Using oSqlCommand As New System.Data.SqlClient.SqlCommand(sql, oSqlConnection)
oSqlCommand.Parameters.Add("#Email", SqlDbType.VarChar).Value = email.Text
oSqlCommand.Parameters.Add("#Password", SqlDbType.VarChar).Value = password.Text
oSqlConnection.Open()
Using oSqlDataReader = oSqlCommand.ExecuteReader()
If oSqlDataReader.Read() Then
Dim emailColIndex = oSqlDataReader.GetOrdinal("Email")
Dim pwdColIndex = oSqlDataReader.GetOrdinal("Password")
email = oSqlDataReader.GetString(emailColIndex)
password = oSqlDataReader.GetString(pwdColIndex)
End If
End Using
End Using
End Using ' oSqlConnection.Close() not needed with using '
If email IsNot Nothing AndAlso password IsNot Nothing Then
End If
But instead of initializing two string variables you should implement a Login class that you can initialize and return from the method. You don't want to know the email and the password since you already have them.
Since this is ASP.NET i suggest to look at the available membership provider which are powerful and have a learning curve, but it's definitely worth the time.
I am trying to create a simple form for users to input data to book a course. They fill in the textboxes and press submit, and it needs to send an email to me with the information (I have this working) and it also needs to add it to a database (this is what I am struggling with). I also really need to understand the code so I can use it again in future.
I am making a new database/form just to get this working, then I will implement it to my working form that sends email as well.
Currently I have created a database with one table, containing: ID, Name, Course Name and Address
I have created a form with 3 text boxes (txtName, txtCourseName and txtAddress) with a submit button, but from here I am not sure how to make it so I put values in the textboxes, click the submit button and they are added to the database. Any help would be great, thanks.
Fred
Just create 3 textboxes and 1 button on the form copy all this code, dont forget to name the textboxes accordingly
Imports System.Data
Imports System.Data.OleDb
Public Class Form1
Dim Con As OleDbConnection
Dim cmd As New OleDbCommand
Dim conString As String = "This part you have to do it your self you can go to this link to check whick string works for u http://www.connectionstrings.com/"
Public Sub CourseSave()
Try
Dim con As New OleDbConnection
con.ConnectionString = conString
con.Open()
cmd.Connection = con
cmd.CommandText = "insert into tablename(Name, [Course Name], Address) values('" & Me.txtName.Text & "', '" & Me.txtCourseName.Text & "', '" & Me.txtAddress.Text & "')"
cmd.ExecuteNonQuery()
con.Close()
MsgBox("New Course Saved")
con.Close()
con.Dispose()
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
CourseSave()
End Sub
End Class
if you still get errors post me the error I might be able to help you.
If you are comfortable with adding a dataset to your project,
(Right Click Project > Add > New Item > Data > Dataset)
Add a Table Adapter and build a SQL Select statement similar to the one below using Query Builder (which will also create your INSERT statement)
Select txtName, txtCourseName , txtAddress From MyTable
You can then call the Insert statement from your button code, along the lines of...
Dim sta As New YourDataTableAdapter.TableAdapter
sta.Insert(txtName, txtCourseName , txtAddress)
sta.Dispose()
http://msdn.microsoft.com/en-us/library/6sb6kb28.aspx