Vb.net sql help needed

[Gmez]

Hi there, I'm a bit of a newbie to vb express 2008 and need a bit of assistance please!

I have 3 tables in a database (Order, Personnel, Products) and need to be able to manipulate the data. I (think I) know the commands to use are SELECT ... FROM, INPUT, DELETE but I have no idea when it comes to establishing a connection to the database so that the data can be manipulated.

The various input data (such as surname, DOB etc) comes from various textboxes that I have created on a form and this is then transfered to variables from which I hope to enter into the database when a button is clicked.

I've been tearing my hair out over this so any help would be very much appreciated!

[jg007]

basically you will need to establish a connection and then run a query against the database to return a set of data which you can then use as required

there are plenty of tutorials on the web , from a quick google this one looks pretty straight forward - Part 2 - Using ADO .NET - Access and OleDB

if you have specific questions on the code feel free to post but as with many other sites it is better if you try to work things out first and then ask about problems you experience with the code.

[lotus18]

Could you specify what database are you using?

Rey Sean

[jg007]

sorry, I should have added -

I presume that you are using an SQL server and although the link I have given is for Access it is pretty much the same except for the connection strings

[Gmez]

Hey thanks for the replies.

I'm using an SQL database that I have set up inside the IDE. The thing that currently confuses me is the use of the connection strings but I'm sure that more confusion will arise afterwards!

I'll have a read of the link and investigate further.

Edit: I've also stumbled upon a guide Link which I'll have a look at.

Thanks again :)

[Gmez]

Ok having had a look at the guide I found I've come up with this:

Dim connection_string As String = "data source=C:\Documents and Settings\Home\Desktop\VB\Project\Database.sdf" 
        Dim db_con As SqlConnection
        Dim sql_con As New SqlCommand
 
        db_con = New SqlConnection(connection_string)
        sql_con.Connection = db_con
        sql_con.CommandType = CommandType.Text
        sql_con.CommandText = "INSERT INTO PERSONNEL(Username, Password, First name, Surname, DOB, Start date, Status)""VALUES (@Username, @Password, @First name, @Surname, @DOB, @Start date, @Status)"
 
        sql_con.Parameters.Add("@Employee ID", SqlDbType.NVarChar).Value = 4
        sql_con.Parameters.Add("@Username", SqlDbType.NText).Value = username
        sql_con.Parameters.Add("@Password", SqlDbType.NText).Value = password
        sql_con.Parameters.Add("@First name", SqlDbType.NText).Value = first_name
        sql_con.Parameters.Add("@Surname", SqlDbType.NText).Value = surname
        sql_con.Parameters.Add("@DOB", SqlDbType.Date).Value = DOB
        sql_con.Parameters.Add("@Start date", SqlDbType.Date).Value = start_date
        sql_con.Parameters.Add("@Status", SqlDbType.NChar).Value = status
 
        Try
            db_con.Open()
            sql_con.ExecuteReader()
            db_con.Close()
        Catch ex As Exception
 
        End Try
 

However when I exit the program nothing has changed in the database. Does what I'm doing at the moment actually save the database once the data has been inserted?

Cheers

[truezplaya]

"INSERT INTO PERSONNEL(Username, Password, First name, Surname, DOB, Start date, Status)""VALUES (@Username, @Password, @First name, @Surname, @DOB, @Start date, @Status)"

Don't you have a few too many " in your sql string?
They should only be around the sql string like so

"INSERT INTO PERSONNEL(Username, Password, First name, Surname, DOB, Start date, Status) VALUES (@Username, @Password, @First name, @Surname, @DOB, @Start date, @Status)"

[Gmez]

Thanks for the tip, although I'm still not sure what to do to get it to save! I've replaced:

db_con.Open()
sql_con.ExecuteReader()
db_con.Close()

with

db_con.Open()
sql_con.ExecuteNonQuery()
db_con.Close()

but still no difference. :(

Edit: Ok having put a message box to open in the event of an exception it's come out with this:

Can anyone decipher that? Thanks again.

[raids51]

yea basically that error message is telling you that your server doesnt accept remote sql connections... is the server in your local network? changing the properties on the server to allow remote sql connections might do the trick, or it might be something else... either way im not necessarily the person to ask about fixing it, im not all that good at networking but i hope this helped