I have this code that populates a datagridview with data from ms access:
Dim con As New OleDbConnection
Dim ds As New DataSet
Dim da As OleDb.OleDbDataAdapter
Dim Sql As String
Sql = "SELECT * FROM myTable WHERE case_no=?"
Try
con.ConnectionString = "PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source=Sample.accdb;Persist Security Info=True;Jet OLEDB:Database Password=dbadmin2010"
con.Open()
Dim cmd As OleDbCommand = New OleDbCommand(Sql, con)
da.SelectCommand = cmd
cmd.Parameters.AddWithValue("case_no", case_no)
Dim ds As DataSet = New DataSet
da.Fill(ds, "Case Info")
DataGridView1.DataSource = ds.Tables("Case Info")
Catch ex As Exception
MsgBox(ex.Message)
End Try
Now I had just finished creating a query from design view within MS Access itself, is there a way to call that query and retrieve the results to my datagridview?
Just use the query name and set the command type, for example, in addition to what you already have, you can use the following notes:
Try
con.ConnectionString = enter_connection_string_here
con.Open()
cmd.Connection = con
cmd.CommandType = CommandType.StoredProcedure
cmd.CommandText = "NameOfQuery"
da.SelectCommand = cmd
cmd.Parameters.AddWithValue("case_no", case_no)
da.Fill(ds, "Case Info")
Related
Following is the code am using to bind the grid, can anyone please suggest me what am doing wrong in this snippet
Dim con As New SqlClient.SqlConnection
Dim ds As New DataSet
Dim adapter As SqlDataAdapter
Dim sql As String
con.ConnectionString = "Data Source=SHAHRUKH-PC\SQLEXPRESS;Initial Catalog=vb;User ID=sa;Password=sa#1234"
con.Open()
sql = "Data Source=SHAHRUKH-PC\SQLEXPRESS;Initial Catalog=vb;User ID=****;Password=*****"
cmd.CommandText = "select * From demo_vb Where ID = '" & txtbox4.Text & "'"
adapter = New SqlClient.SqlDataAdapter
adapter.Fill(ds)
GridView1.ItemsSource = New DataView()
GridView1.DisplayMemberPath = "ID"
con.Close()
I get this error:
The SelectCommand property has not been initialized before calling 'Fill'
try following code:
SqlCommand cmd;
SqlConnection con = new SqlConnection("Data Source=SUNTECH-PC\\SQLEXPRESS;Initial Catalog=iSense;Integrated Security=True;");
con.Open();
cmd = new SqlCommand("Select Picture from Images",con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
con.Close();
I think this would help
Dim con As New SqlClient.SqlConnection("Data Source=SHAHRUKH-PC\SQLEXPRESS;Initial Catalog=vb;User ID=sa;Password=sa#1234")
Dim ds As New DataSet
Dim sql As New SqlCommand("select * From demo_vb Where ID = '" & txtbox4.Text & "'",con)
Dim adapter As New SqlDataAdapter(sql)
con.Open()
adapter.Fill(ds)
GridView1.datasource = ds.Tables(0)
GridView1.databind()
con.Close()
I have a question, I want to add a TabPage to my TabControl from an access record? I think it's something along these lines but it didn't work:
Dim con As OleDbConnection = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & My.Application.Info.DirectoryPath.ToString() & "\data\testing.Accdb;Persist Security Info=False;")
con.Open()
Dim constr As String = "SELECT ProductType, Discription FROM TblProductType"
Dim cmd As OleDbCommand = New OleDbCommand(constr, con)
Dim da As OleDbDataAdapter = New OleDbDataAdapter(cmd)
Dim ds As DataSet = New DataSet()
da.Fill(ds, "TblProductType")
Me.TabControl1.TabPages.Add("Discription")
con.Close()
You have to iterate over the row collection of the table:
Using cmd As New OleDbCommand("SELECT ProductType, Discription FROM TblProductType", con)
Using rdr As OleDbDataReader = cmd.ExecuteReader
While rdr.Read
TabControl1.TabPages.Add(rdr("Discription").ToString)
End While
End Using
End Using
Of course, this only gives you an empty TabPage for every record and in it's current implementation, you don't have any reference to the record anymore. That ProductType, if it's unique, should be used somewhere, too.
This question already has an answer here:
Table doesn't have a primary key
(1 answer)
Closed 9 years ago.
I can't search my datatable. It keeps repeating the same error "table doesn't have a primary key." and I don't know what to do. I already added the .FillSchema, but it still won't work. I'm using Visual Basic.
Dim con As New OleDb.OleDbConnection
Dim da As New OleDb.OleDbDataAdapter
Dim ds As New DataSet
Dim sql As String
Dim pass As Integer
Dim cmd As New OleDb.OleDbCommand
Dim dr As OleDb.OleDbDataReader
Dim dRow As DataRow
con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Drug Emporium.accdb"
con.Open()
cmd.CommandText = "Select * From Inventory"
cmd.CommandType = CommandType.Text
cmd.Connection = con
sql = "Select * From Inventory"
dr = cmd.ExecuteReader()
da = New OleDb.OleDbDataAdapter(sql, con)
da.FillSchema(ds, SchemaType.Source, "Drug Emprorium")
da.Fill(ds, "Drug Emporium")
Dim cb As New OleDb.OleDbCommandBuilder(da)
dRow = ds.Tables("Drug Emporium").Rows.Find(intItemNum)
dRow.Delete()
con.Close()
I tried this but it still didn't work. It now gives a null reference exception on the Delete()
con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Drug Emporium.accdb"
con.Open()
cmd.CommandText = "Select * From Inventory"
cmd.CommandType = CommandType.Text
cmd.Connection = con
sql = "Select * From Inventory"
da = New OleDb.OleDbDataAdapter(sql, con)
da.Fill(ds, "Drug Emporium")
da.FillSchema(ds, SchemaType.Source, "Drug Emprorium")
Dim cb As New OleDb.OleDbCommandBuilder(da)
ds.Tables("Drug Emporium").PrimaryKey = New DataColumn() {ds.Tables("Drug Emporium").Columns("InventoryNumber")}
dRow = ds.Tables("Drug Emporium").Rows.Find(intItemNum)
dRow.Delete()
con.Close()
Your Problem is in the Table structure. You should normally show the DDL (SQL to create the table), but I understand it is uncommon with Access.
Anyway, I suspect your error happens in the delete: if you want to modify an resultset some Drivers need a primary key in the Table (and the selected colums) in order to be able to sent a clear modification operation back to the DB.
I am trying to fill a combobox with a SQL Result
I think my problem is handling the data in the datatable form.
Dim sql As String
Dim sqlquery As String
Dim ConnectionString As String
ConnectionString = "Data Source=(local);Initial Catalog=Control;Persist Security Info=True;User ID=user;Password=pass"
sqlquery = "Select dbName from Databases"
Using connection As SqlConnection = New SqlConnection(ConnectionString)
connection.Open()
Using conn As SqlCommand = New SqlCommand(sqlquery, conn)
Dim rs As SqlDataReader = comm.ExecuteReader
Dim dt As DataTable = New DataTable
dt.Load(cmboxDatabaseName)
End Using 'comm
End Using 'conn
When I run the program I just stare at a sad empty combobox.
Almost right, but you need to Load the datatable using the DataReader.
Then assing the DataTable to the DataSource of the Combo
Using connection As SqlConnection = New SqlConnection(ConnectionString)
connection.Open()
Using comm As SqlCommand = New SqlCommand(sqlquery, connection)
Dim rs As SqlDataReader = comm.ExecuteReader
Dim dt As DataTable = New DataTable
dt.Load(rs)
' as an example set the ValueMember and DisplayMember'
' to two columns of the returned table'
cmboxDatabaseName.ValueMember = "IDCustomer"
cmboxDatabaseName.DisplayMember = "Name"
cmboxDatabaseName.DataSource = dt
End Using 'comm
End Using 'conn
Also you could set the combobox ValueMember property to the name of the column that you will use as key for future processing and the DisplayMember property to the column name that you want to display as text to choose from for your user
you can also do it as
Dim Con = New SqlConnection(_ConnectionString)
Dim cmdAs New SqlCommand
Dim dr As New SqlDataReader
Try
If Con.State = ConnectionState.Closed Then
Con.Open()
cmd.Connection = Con
cmd.CommandText = "Select field1, field2 from table"
dr = cmd.ExecuteReader()
' Fill a combo box with the datareader
Do While dr.Read = True
ComboBoxName.Items.Add(dr.GetString(0))
ComboBoxName.Items.Add(dr.GetString(1))
Loop
Con.Close()
End If
Catch ex As Exception
MsgBox(ex.Message)
End Try
Hope it works for you.
I've managed to get the following code...
con.ConnectionString = My.Settings.dbConnection
Dim sqlCmd As System.Data.OleDb.OleDbCommand = New System.Data.OleDb.OleDbCommand()
con.Open()
sqlCmd.Connection = con
Dim schemaTable As DataTable
schemaTable = con.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Views, Nothing)
To retrieve a list of Views in my Access database, but now I want to retrieve the results based on a selected View.
Is there a correct method in doing this, or do I take the SQL Statement from the DataTable returned for each row?
Suppose you have Query1 (View) in your Access database (Database1.accdb file). The following code will output each row of the query to the console (for demo purposes):
Dim con As OleDbConnection = New OleDbConnection()
con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Database1.accdb;Persist Security Info=False;"
Dim sqlCmd As OleDbCommand = New System.Data.OleDb.OleDbCommand()
sqlCmd.CommandType = CommandType.StoredProcedure
sqlCmd.CommandText = "Query1"
sqlCmd.Connection = con
con.Open()
Dim reader As OleDbDataReader
reader = sqlCmd.ExecuteReader()
If reader.HasRows Then
While reader.Read()
Console.WriteLine(reader("Column1")) 'output specific column
End While
End If
Console.ReadLine()
Hope this helps