C# -> Retrieving dataset from SQL Server 2008 - c#

I have a table called NAMES in my SQL Server database. I am trying to retrieve the entire table and put it into a dataset:
//get the connection string from web.config
string connString = ConfigurationManager.ConnectionStrings["Platform"].ConnectionString;
DataSet dataset = new DataSet();
using (SqlConnection conn = new SqlConnection(connString))
{
SqlDataAdapter adapter = new SqlDataAdapter();
adapter.SelectCommand = new SqlCommand("NAMES", conn);
adapter.Fill(dataset);
}
This throws a sql exception though,
"Invalid Object Name NAMES"...
What am I doing wrong?

Open the connection !!!!!!
//get the connection string from web.config
string connString = ConfigurationManager .ConnectionStrings["Platform"].ConnectionString;
DataSet dataset = new DataSet();
using (SqlConnection conn = new SqlConnection(connString))
{
SqlDataAdapter adapter = new SqlDataAdapter();
adapter.SelectCommand = new SqlCommand("select * from [NAMES]", conn);
conn.Open();
adapter.Fill(dataset);
}

You're not passing an actual SQL select command to the SqlCommand constructor.

First check whether Select * from dbo.[Names] is wroking in ur sql ?
string connString = ConfigurationManager .ConnectionStrings["Platform"].ConnectionString;
Dataset ds=new Dataset();
SqlConnection con = new Sqlconnection(connString);
SqlDataAdapter adapter = new SqlDataAdapter("Select * from dbo.[Names]",con);
adapter.Fill(ds);

Related

SQLConnection bringing data to TextBox

I know this looks really simple but i've been looking for an answer for hours with no luck.
I want to fill my row values into a bunch of textboxes. How can I specify that [CompanyName] is going to be used by the companyName textbox? Please keep it as simple as possible (beginner level).
string customerUniqueID = "test";
string constr = ConfigurationManager.ConnectionStrings["SQLConnection"].ToString(); // connection string
SqlConnection con = new SqlConnection(constr);
con.Open();
SqlCommand com = new SqlCommand("SELECT * FROM [Customers] WHERE [UniqueID] = #UniqueID", con); // table name
com.Parameters.Add("#UniqueID", SqlDbType.Int);
com.Parameters["#UniqueID"].Value = customerUniqueID;
SqlDataAdapter da = new SqlDataAdapter(com);
DataSet ds = new DataSet();
companyName.Text = ?????????
string customerUniqueID = "test";
string constr = ConfigurationManager.ConnectionStrings["SQLConnection"].ToString(); // connection string
SqlConnection con = new SqlConnection(constr);
con.Open();
SqlCommand com = new SqlCommand("SELECT * FROM [Customers] WHERE [UniqueID] = #UniqueID", con); // table name
com.Parameters.Add("#UniqueID", SqlDbType.Int);
com.Parameters["#UniqueID"].Value = customerUniqueID;
SqlDataAdapter da = new SqlDataAdapter(com);
DataSet ds = new DataSet();
da.Fill(ds, "Customers");
companyName.Text = ds.Tables[0].Rows[0]["CompanyName"].ToString();
I will recommend some changes in your code:
Your sql query returning result from one set, so you can use DataTabe instead of DataSet.
To fill results from DB to your DataTable you can use SqlAdapter.Fill() method.
Use Field() generic method (more examples of Field()) to get values from your DataTable.
Use using blocks for disposable objects, or at least make sure you've closed them after.
There is no need of con.Open() to open connection when using Fill() method, because from MSDN:
The Fill method implicitly opens the Connection that the DataAdapter is using if it finds that the connection is not already open. If Fill opened the connection, it will also close the connection when Fill is finished. This can simplify your code when dealing with a single operation such as a Fill or an Update.
string customerUniqueID = "test";
string constr = ConfigurationManager.ConnectionStrings["SQLConnection"].ToString(); // connection string
using(SqlConnection con = new SqlConnection(constr))
{
SqlCommand com = con.CreateCommand();
com.CommandText = "SELECT * FROM [Customers] WHERE [UniqueID] = #UniqueID";
com.Parameters.Add("#UniqueID", SqlDbType.Int);
com.Parameters["#UniqueID"].Value = customerUniqueID;
using(SqlDataAdapter da = new SqlDataAdapter(com))
{
DataTable dt = new DataTable();
da.Fill(dt);
companyName.Text = dt.Rows[0].Field<string>("CompanyName");
}
}
Please feel free to comment, if I missed something.

Fill combobox from SQL database with specific parameter

I have problem to get specific value from sql server with parameter can anybody explain me why it works on winfom but not on wpf and how i can fix it
my code:
private void UpdateItems()
{
COMBOBOX1.Items.Clear();
SqlConnection conn = new SqlConnection(Properties.Settings.Default.constring.ToString());
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM CLIENT where cod_cli='some_specific_string'", conn);
DataSet ds = new DataSet();
da.Fill(ds, "CLIENT");
COMBOBOX1.ItemsSource = ds.Tables[0].DefaultView;
COMBOBOX1.DisplayMemberPath = ds.Tables[0].Columns["FR"].ToString();
COMBOBOX1.SelectedValuePath = ds.Tables[0].Columns["FC"].ToString();
}
The program when execute this function crash with error:
System.Data.SqlClient.SqlException: 'Invalid column name
'some_specific_string'.'
the solution is
SqlConnection sqlConnection = new SqlConnection(Properties.Settings.Default.constring.ToString());
{
SqlCommand sqlCmd = new SqlCommand("SELECT * FROM CLIENTS where cod_cli=#cod", sqlConnection);
sqlCmd.Parameters.AddWithValue("#cod", cod_cli.Text);
sqlConnection.Open();
SqlDataReader sqlReader = sqlCmd.ExecuteReader();
while (sqlReader.Read())
{
COMBOBOX1.Items.Add(sqlReader["FR"].ToString());
}
sqlReader.Close();
}
The query doesn't recognize string as parameter but adding as SQL parameter it works.
SqlConnection conn = new SqlConnection(Properties.Settings.Default.constring.ToString());
conn.Open();
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM CLIENT where cod_cli='some_specific_string'", conn);
DataSet ds = new DataSet();
da.Fill(ds, "CLIENT");
//Populate the combobox
COMBOBOX1.ItemsSource = ds.Tables[0].DefaultView;
COMBOBOX1.DisplayMemberPath = "FR";
COMBOBOX1.SelectedValuePath = "FC";
where "FR" and "FC" are existing columns in your SELECT Query.

datagrid doesn't bind with datatable

I'm working on a webpage in azure. Here's a part of my code:
using (SqlConnection conn = new SqlConnection("my connection string"))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM Students", conn);
conn.Open();
SqlDataAdapter _adp = new SqlDataAdapter(cmd);
DataTable ds = new DataTable();
_adp.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
}
Off course that instead of "my connection string" there's the real one...
The problem is that the page loads but without the gridview for some reason...
Any help will be great, Thanks
EDIT: I also tried with datasets, like this:
using (SqlConnection conn = new SqlConnection("my connection string"))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM Students", conn);
conn.Open();
SqlDataAdapter _adp = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
_adp.Fill(ds);
GridView1.DataSource = ds.Tables[0];
GridView1.DataBind();
}
Try with GridView1.DataSource = ds.Tables[0];
whole code will look as follows:
using (SqlConnection conn = new SqlConnection("my connection string"))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM Students", conn);
conn.Open();
SqlDataAdapter _adp = new SqlDataAdapter(cmd);
DataSet ds = new DataTable();
_adp.Fill(ds);
GridView1.DataSource = ds.Tables[0];
GridView1.DataBind();
}

Error in filling dataset with oledb

I am getting
"No value given for one and more required parameter"
from below code everything looks fine not able to find the problem.
string myConnectionString= #"Provider=Microsoft.Jet.OLEDB.4.0; Data source=D:\TiptonDB.mdb";
string query = "SELECT NodeID FROM NDDINodes";//"SELECT O.NodeID, N.NodeID FROM NDDINodes AS N, NDDINodes AS O WHERE N.X=O.X And N.Y=O.Y And N.NodeID<>O.NodeID";
DataSet dt = new DataSet();
using (OleDbConnection myConnection = new OleDbConnection())
{
myConnection.ConnectionString=myConnectionString;
OleDbCommand cmd=new OleDbCommand ();
cmd.Connection=myConnection;
// cmd.CommandText="SELECT O.NodeID, N.NodeID FROM NDDINodes AS N, NDDINodes AS O WHERE N.X=O.X And N.Y=O.Y And N.NodeID<>O.NodeID";
myConnection.Open();
OleDbDataAdapter ad = new OleDbDataAdapter(query,myConnection);
ad.Fill(dt);
}
string myConnectionString= #"Provider=Microsoft.Jet.OLEDB.4.0; Data source=D:\TiptonDB.mdb";
string query = "SELECT NodeID FROM NDDINodes";//"SELECT O.NodeID, N.NodeID FROM NDDINodes AS N, NDDINodes AS O WHERE N.X=O.X And N.Y=O.Y And N.NodeID<>O.NodeID";
DataSet dt = new DataSet();
OleDbConnection objXConn = new OleDbConnection(myConnectionString);
objXConn.Open();
OleDbCommand objCommand = new OleDbCommand(query, objXConn);
OleDbDataAdapter adp = new OleDbDataAdapter(objCommand);
adp.Fill(dt);
objXConn.Close();
Make sure your connection string isn't missing data: UserName/Password, Persist Security Info=True,...
Check this link for access connectionString settings.
just add this in your code
OleDbDataAdapter ad = new OleDbDataAdapter();
ad.SelectCommand = new OleDbCommand(query, myConnection);

Create/Display DataGrid from a table (database) C#

I'm trying show a DataGrid in C# (for app WindowsMobile). I have a database ("pruebaDB.sdf") in DataConnections and one table ("tablaMercancia").
Also in DataSource I have "pruebaDBDataSet" and "tablaMercancia".
How I can show data table in a DataGrid?
I use a SmartDevice project (I can't to use DataGridView, only I use DataGrid).
I can show a new table (created for code) in a DataGrid, but I don't know to show an existing table in my database.
string conSTR = "Data Source=" + (System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase)) + "\\pruebaDB.sdf;Persist Security Info=False";
SqlCeConnection connection = new SqlCeConnection(conSTR);
string sql = "SELECT * FROM tablaMercancia";
connection.Open();
SqlCeCommand cmd = new SqlCeCommand(sql, connection);
SqlCeDataAdapter da = new SqlCeDataAdapter(cmd);
//...............
//...Any idea?
//...............
connection.Close();
Any ideas please?
Thanks!!!
Please, Change Datagridview name as per below :
string conSTR = "Data Source=" + (System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase)) + "\\pruebaDB.sdf;Persist Security Info=False";
SqlCeConnection connection = new SqlCeConnection(conSTR);
string sql = "SELECT * FROM tablaMercancia";
connection.Open();
SqlCeCommand cmd = new SqlCeCommand(sql, connection);
SqlCeDataAdapter da = new SqlCeDataAdapter(cmd);
DataSet ds=new DataSet();
da.Fill(ds);
//datagridview1 is name of datagridview in form:
datagridview1.DataSource=ds.Tables[0];
connection.Close();
Try this.
string sql = "SELECT * FROM tablaMercancia";
connection.Open();
//SqlCeCommand cmd = new SqlCeCommand(sql, connection);
SqlCeDataAdapter da = new SqlCeDataAdapter(sql, connection);
DataSet ds=new DataSet();
da.Fill(ds);
designing page track the gridview or data grid
1st use namespace using System.Data,SqlClient;
sqlconnection con=new sqlconnection("string path");
con.open();
sqldataadapter da=new sqldataadapter("select * from emp",con);
dataset ds=new dataset();
da.fill(ds,"emp");
gridview1.datasource=ds;
gridview1.databind();

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