So I'm using this post as a last resort, newcomer here, my connection string currently looks like this for my local MSSQL database:
Dim Conn As New SqlConnection("Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=C:\Users\steve\OneDrive\Desktop\UNIT 5 CS\MonmouthCanoeAndActivityCentre\MonmouthCanoeAndActivityCentre\.vs\MonmouthCanoeAndActivityCentre\.vs\MonmouthCanoeAndActivityCentre\v16\WorkerLogin.mdf;Integrated Security=True;Connect Timeout=30")
which is of course incredibly clunky and also hard coded to my personal laptop. My problem is that I want to be able to run the connection on any new device I send the project to without them having to change the directory of the connection string themselves.
Any advice would be helpful, I'm not incredible at visual basic either so sorry if I question.
Answering my own question to hopefully help some poor future soul.
the new connection string is:
Dim conn As New SqlConnection("Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=" & Application.StartupPath & "InsertFileNameHere.mdf;Integrated Security=True;Connect Timeout=30")
The .mdf file of your database has to be in the same place as your Application.StartupPath but you can find this with a simple:
Dim location As String = Application.StartupPath
MessageBox.Show(location)
and a test button to activate the above ^
Related
My application uses a database stored in a file available via network. So far, I've been using a MS-Access file (.accdb), but I'm trying to migrate to SQLite Version 3 (.db3).
I added SQLite NuGet package to my project and created a SQLite database using SQLiteStudio. I refactored my database objects to work with System.Data.SQLite.SQLiteConnection instead of System.Data.OleDb.OleDbConnection and it worked well.
However, my previous accdb database was password protected, and I don't know how to apply a password over my current SQLite database.
Can anyone teach me ho to do it? Thanks in advance!
I followed the link which Wudge kindly appointed in comment above, and it works, but I'd rather clarify what need to be done:
To set a password to an unprotected database:
Dim conn = New SQLite.SQLiteConnection(
"Data Source=C:\yourFolder\yourDB.db3;Version=3;")
conn.Open()
conn.ChangePassword("password")
conn.Close()
To open a password-protected database:
Dim conn = New SQLite.SQLiteConnection(
"Data Source=C:\yourFolder\yourDB.db3;Version=3;")
conn.SetPassword("password")
conn.Open()
conn.Close()
or
Dim conn = New SQLite.SQLiteConnection(
"Data Source=C:\yourFolder\yourDB.db3;Version=3;Password=password;")
conn.Open()
conn.Close()
To remove password from a password-protected database:
Dim conn = New SQLite.SQLiteConnection(
"Data Source=C:\yourFolder\yourDB.db3;Version=3;Password=password;")
conn.Open()
conn.ChangePassword(String.Empty)
conn.Close()
PS. The open source database manager SQLiteStudio is able to open files which were password-protected that way, as long as you choose System.Data.SQLite instead of Sqlite 3 as your database type. (Requires v 3.1.1, the current version).
I'm quite confused why the data that I added was not saved to the database.
While my program is running there are no problems in updating the data that is shown in DataGridView but when I close the program, the added data disappears.
I tried to show table data but there were no new data added. Can you tell me what is the problem?
This is my code:
Dim con As New SqlClient.SqlConnection
Dim cmd As New SqlClient.SqlCommand
Dim adaptor As New SqlClient.SqlDataAdapter
Dim dataset As New DataSet
con.ConnectionString = ("Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True")
con.Open()
cmd.CommandText = "INSERT INTO [Table](FirstName,LastName,MI,Address,Email) VALUES(#FN,#LN,#MI,#AD,#EM)"
cmd.Connection = con
cmd.Parameters.Add("#FN", SqlDbType.VarChar).Value = TextBox1.Text
cmd.Parameters.Add("#LN", SqlDbType.VarChar).Value = TextBox2.Text
cmd.Parameters.Add("#MI", SqlDbType.VarChar).Value = TextBox3.Text
cmd.Parameters.Add("#AD", SqlDbType.VarChar).Value = TextBox4.Text
cmd.Parameters.Add("#EM", SqlDbType.VarChar).Value = TextBox5.Text
cmd.ExecuteNonQuery()
MsgBox("Added!")
con.Close()
Me.TableTableAdapter.Fill(Me.Database1DataSet.Table)
The whole AttachDbFileName= approach is flawed - at best! When running your app in Visual Studio, it will be copying around the .mdf file (from your App_Data directory to the output directory - typically .\bin\debug - where you app runs) and most likely, your INSERT works just fine - but you're just looking at the wrong .mdf file in the end!
If you want to stick with this approach, then try putting a breakpoint on the myConnection.Close() call - and then inspect the .mdf file with SQL Server Mgmt Studio Express - I'm almost certain your data is there.
The real solution in my opinion would be to create your database on the server using a management tool (like SSMS Express), give it a logical name (e.g. MyDatabase), and then connect to it using its logical database name (given when you create it on the server). Don't mess around with physical database files and user instances. In that case, your connection string would be something like:
Data Source=.\\SQLEXPRESS;Database=MyDatabase;Integrated Security=True
and everything else is exactly the same as before...
Also see Aaron Betrand's blog post Bad Habits to Kick - using AttachDbFileName for more background info
I have been searching for a couple hours, and found several questions, but none of them really explained this in a way I can understand.
I'm programming a game similar to Rock Paper Sissors, except with many more selections, and the possiblity of a tie. I had originally hardcoded all of the possible outcomes, then decided to try a database so I can learn and practice sql as well.
Problem is, I can't figure out for the life of me how to connect to my local database, now that I have set it up and filled it through Visual Studio 2010. I can connect to it through Server Explorer just fine, and I can see it in Solution Explorer. I've tried several things, along the lines of:
Private sqlConn As New SqlConnection("Data Source=(local)|DataDirectory|\Outcomes.sdf;database=Outcomes;Integrated Security=true")
Private sqlConn As New SqlConnection("Data Source=.\SQLEXPRESS; Integrated Security=true")
Dim sqlConn As SqlConnection
sqlConn = New SqlConnection("DataSource=..\..\Outcomes.sdf")
I am relatively new to sql, but know enough through tinkering to build a sql statement and get me the result I want. But I've never connected to a database before. I've looked on MSDN and tried several things I saw on there (everything that looked like what I needed, really) but it still hasn't worked.
If I can connect, I already have my statement set, and have tested it through the database itself. Any help would be wonderful, especially if it's explained in a way I can understand it and use it for later.
Also, if it helps and isn't noticed through my tried code, my db name is Outcomes. I don't know if that is needed or will help, but just in case.
Please visit connection strings here...
It also would have been helpful to know what type of DBMS you are using as well. I noticed you have an .sdf database file, not a DBMS (For ex: MySql, SQL or Oracle). Therefore, your connection string is really going to depend on what you want.
Your issue is here by the way...
Private sqlConn As New SqlConnection("Data Source=(local)|DataDirectory|\Outcomes.sdf;database=Outcomes;Integrated Security=true")
*You cant use the SqlConnection you have because its not supported with the use of .sdf files.
Instead you have to use: System.Data.SqlServerCe 'This is for compact edition
If you would like to know more about this please see here.
Kendra,
Here are the logical Steps you will need to follow to access the database programmatically:
Note: I'm assumming you have the proper SQLExpress | SQL Server Database setup whether local or remote the methods below are identical except for the connection string information.
1) Import the Sql AdoNet Namespace so you can use the proper SQL Server Client Objects & Methods;
a) Imports System.Data.SqlClient
2) Establish a Connection to the database with the ADO Connection Object:
' Create your ADO Connection Object:
Private myConn As SqlConnection
myConn = New SqlConnection("Initial Catalog=OutComes;" & _
"Data Source=localhost;Integrated Security=SSPI;")
Note: This connection string uses integrated security from your windows machine. you could also use standard security where you would need to enter your username and password credentials. Its your choice.
3) Setup Your ADO Command Object to Define your data retrieval query:
'Create a Command object.
Private myCmd As SqlCommand
myCmd = myConn.CreateCommand
myCmd.CommandText = "SELECT FirstName, LastName FROM Employees"
'Open the connection.
myConn.Open()
Note: Subsitute CommandText string for your actual query based upon your own database schema.
4) Read, Fetch, Display Data using the SQLDataReader Object:
Private results As String
Private myReader As SqlDataReader
myReader = myCmd.ExecuteReader()
'Traverse the DataSet and Display in GUi for Example:
Do While myReader.Read()
results = results & myReader.GetString(0) & vbTab & _
myReader.GetString(1) & vbLf
Loop
'Display results.
MsgBox(results)
5) Gracefully Close all Objects Used:
' Close the reader and the database connection.
myReader.Close()
myConn.Close()
Note - You'll need to consult microsoft for further connection string formats, since I don't have enough info. But this should clarify the actual big picture steps for you.
Regards,
Scott
I have inherited software to maintain. The previous version used a third party Datagridview substitute that isn't compatible with versions of Windows from Vista on. In attempting to put Datagridviews in I have run into a problem with connecting to the database.
I am trying to make a small program to play around with connection and SELECT outside of the original software so I can further understand what I am doing and without going through the full process of using the original software to get to the testing point.
Private Shared Function GetData(ByVal sqlCommand As String) As DataTable
Dim table As New DataTable()
Dim connectionString As String = "Data Source=.\SQLExpress;Integrated Security=true;" _
& "AttachDbFilename=C:blah\blah\blah.mdf;User Instance=true;"
Using con = New SqlConnection(connectionString)
Using command = New SqlCommand(sqlCommand, con)
Using da = New SqlDataAdapter(command)
da.Fill(table)
End Using
End Using
End Using
Return table
End Function
My SQL command is a simple "Select * FROM Setup" and the rest of the program is form loads, imports, and DataGridView formatting. I don't think it affects the SQL part and would be cumbersome to include here.
This results in what appears to be a closed connection.
![Connection Property] http://i.imgur.com/b5V3Qy5.png
This is a screenshot of my SQLExpress which might help diagnose connection problems.
![SQL Properties] http://i.imgur.com/bakBq5D.png
I've blurred out the computer name in grey, but I did notice that there was another computer name in pink. I don't know what it means other than maybe this database was originally created on another computer and has been copied and pasted.
Finally this is the connection string that the original software used:
"Data Source=.\SQLExpress;AttachDbFilename=C:\blah\blah\blah.mdf;Trust_Connection=Yes;"
I have also tried:
"Data Source=.\SQLExpress;AttachDbFilename=C:\blah\blah\blah.mdf;Trusted_Connection=Yes;User Instance=true"
Finally, this is my exception:
"An attempt to attach an auto-named database for file C:\blah\blah\blah.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share."
I got my alternate connection strings from www.connectionstrings.com.
You are missing the Open() command.
con.Open()
Full code listing. (Also a good idea is to wrap your code in a Try.... End Try block).
Private Shared Function GetData(ByVal sqlCommand As String) As DataTable
Dim table As New DataTable()
Dim connectionString As String = "Data Source=.\SQLExpress;Integrated Security=true;" _
& "AttachDbFilename=C:blah\blah\blah.mdf;User Instance=true;"
Using con = New SqlConnection(connectionString)
conn.Open()
Using command = New SqlCommand(sqlCommand, con)
Using da = New SqlDataAdapter(command)
da.Fill(table)
End Using
End Using
End Using
Return table
End Function
I'm using a SQL Server Compact database (3.5). I have run through every article on this site (and others) I could find about this issue, but can't seem to find the problem. I am using Visual Studio 2012, VB.Net.
My provider string is:
Dim sqlConn As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.SQLServer.CE.OLEDB.3.5;Data Source=" & My.Application.Info.DirectoryPath & "\pw.sdf" & ";Password=XXXyyy1234;Persist Security Info=True;")
My code where it all breaks down is:
'Create SQL Query
Dim SQLString As String = "SELECT * FROM EmailGroups"
'Create Dataset, Open Connection
Dim dsPWC As New DataSet()
Dim OleDbDataAdapter1 As System.Data.OleDb.OleDbDataAdapter = New System.Data.OleDb.OleDbDataAdapter(SQLString, sqlConn)
sqlConn.Open()
And, of course, it breaks down on .Open().
I picked selecting from that datatable because it is a simple one.
EmailGroup_UID [int][PK]
EmailGroup_Name [nvarchar][length=50]
I'm sure I've been simply staring at this too long and can't see the forest for the trees anymore, so I'm hoping someone can slap me straight :)
Thanks in advance.
EDIT: This code all works when tying to the original MS Access 2007 database (accdb). Different provider, of course. And - I didn't import the tables, I re-created manually.
2nd EDIT: Immediate Window says 'A first chance exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll'
You should use SqlCeConnection instead of OldDbConnection.
if you must use OleDbConnection, use "ssce:database password" like so:
"Provider=Microsoft.SQLServer.CE.OLEDB.3.5;Data Source=" & My.Application.Info.DirectoryPath & "\pw.sdf" & ";SSCE:Database Password=XXXyyy1234;Persist Security Info=True;"