How is it I can upload a 20+ mb file to a webserver, but have it timeout when I try to download it? I would think the upload would timeout as well.
Both are using ado.net sqlclient. The event log shows SqlException timeout occurred when attempting to download.
This article looks like a possible lead. But again, why wouldn't it timeout on the upload?
public DataTable ExecuteDataTable(string sql)
{
SqlConnection conn = new SqlConnection();
DataTable dt;
try
{
conn.Open();
SqlCommand dateformatcmd = new SqlCommand("set dateformat " + myDateFormat, conn);
dateformatcmd.ExecuteNonQuery();
SqlDataAdapter da = new SqlDataAdapter(sql, conn);
SqlCommand cmd = new SqlCommand(sql, conn);
//Walk through the parameters
foreach (string name in param.Keys)
{
cmd.Parameters.Add(new SqlParameter(name, param[name]));
}
da.SelectCommand = cmd;
dt = new DataTable();
da.Fill(dt);
}
catch (SqlException)
{
throw;
}
finally
{
if (conn.State == ConnectionState.Open)
{
conn.Close();
}
}
return dt;
}
Related
I've successfully built up my method to execute a select command. It is working fine. Then I change my code for SqlDataAdapter DA = new SqlDataAdapter();
I tried to pass SqlCommand as CommandType.Text in the parameters but I can not do it successfully. I get error. Is there any way if I can pass it as parameters. Please see my code.
Running code (aspx page code)
if ((!string.IsNullOrEmpty(user_login.Value)) && (!string.IsNullOrEmpty(user_pass.Value)))
{
// username & password logic
DataTable dt = new DataTable();
string strQuery = "SELECT 1 FROM TBL_USER_INFO WHERE USERNAME = #USERNAME AND PASSWORD = #PASSWORD";
SqlCommand cmd = new SqlCommand(strQuery);
cmd.Parameters.Add("#USERNAME", SqlDbType.VarChar).Value = user_login.Value.Trim();
cmd.Parameters.Add("#PASSWORD", SqlDbType.VarChar).Value = user_pass.Value.Trim();
DBConnection conn_ = new DBConnection();
dt = conn_.SelectData(cmd);
if (conn_.SQL_dt.Rows.Count > 0)
{
Response.Redirect("Home.aspx", false);
}
}
Successful connection class code
public DataTable SelectData(SqlCommand command)
{
try
{
conn.Open();
SqlDataAdapter DA = new SqlDataAdapter();
command.CommandType = CommandType.Text;
command.Connection = conn;
DA.SelectCommand = command;
DA.Fill(SQL_dt);
return SQL_dt;
}
catch (Exception ex)
{
return null;
}
finally
{
conn.Close();
}
}
How can I pass CommandType.Text as parameters for SqlDataAdapter?
Error code
public DataTable SelectData(SqlCommand command)
{
try
{
conn.Open();
SqlDataAdapter DA = new SqlDataAdapter(command.CommandType.ToString(), conn);
// command.CommandType = CommandType.Text;
// command.Connection = conn;
DA.SelectCommand = command;
DA.Fill(SQL_dt);
return SQL_dt;
}
catch (Exception ex)
{
return null;
}
finally
{
conn.Close();
}
}
I am getting this error:
System.InvalidOperationException: Fill: SelectCommand.Connection property has not been initialized.
at System.Data.Common.DbDataAdapter.GetConnection3(DbDataAdapter adapter, IDbCommand command, String method)...
public DataTable SelectData(string query)
{
DataTable dt = new DataTable();
using (SqlConnection con = new SqlConnection("Your Connection String here"))
{
con.Open();
using (SqlCommand cmd = con.CreateCommand())
{
cmd.CommandText = query;
cmd.CommandType = CommandType.Text;
using (SqlDataAdapter adp = new SqlDataAdapter(cmd))
{
adp.Fill(dt);
return dt;
}
}
}
}
To use:
SelectData("select * from yourTable");
Reds has the answer. Just to clean the code up a little bit...
public DataTable SelectData(string query)
{
using (var connection = new SqlConnection("myConnectionString"))
using (var command = new SqlCommand(query, connection))
using (var adapter = new SqlDataAdapter(command))
{
var dt = new DataTable();
connection.Open();
adapter.Fill(dt);
return dt;
}
}
Actually you should pass the connection object on SQLCommand.Hope it helped you
DBConnection conn_ = new DBConnection();
SqlCommand cmd = new SqlCommand(strQuery,conn_);
The error that you are getting is not related to CommandType.Text, it says you have initialised the connection property of of SelectCommand. Basically you should uncomment "command.Connection = conn;" to get rid of this error. If you still face any other issue , it is better to provide those details in the questions to provide accurate answer.
What is my method missing? It is not returning the data table.
public DataTable GetHotelReportData(int _ratpropid) {
var _connectionString = _isDevelopment ? CommonTypes.Dev : CommonTypes.Prod;
DataTable dt = new DataTable();
dt.Clear();
SqlConnection conn = new SqlConnection(_connectionString);
conn.Open();
SqlCommand cmd = new SqlCommand("ww.HotelRpt_spGenerateData2018", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#RatPropId", _ratpropid);
SqlDataAdapter da = new SqlDataAdapter();
try {
da.SelectCommand = cmd;
da.Fill(dt);
}
catch (Exception _ex) {
new ErrorLogging().Log(_ex);
}
finally {
conn.Close();
da.Dispose();
cmd.Dispose();
}
return dt;
}
Try cutting the data adapter out and just using the command. No need for an adapter as far as I can tell:
public DataTable GetHotelReportData(int _ratpropid) {
var _connectionString = _isDevelopment ? CommonTypes.Dev : CommonTypes.Prod;
DataTable dt = new DataTable();
dt.Clear();
SqlConnection conn = new SqlConnection(_connectionString);
SqlCommand cmd = new SqlCommand("ww.HotelRpt_spGenerateData2018", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#RatPropId", _ratpropid);
try {
conn.Open();
dt.Load(cmd.ExecuteReader);
return dt;
}
catch (Exception _ex) {
new ErrorLogging().Log(_ex);
}
finally {
conn.Close();
cmd.Dispose();
}
}
If that doesn't work, try executing your stored procedure natively in SSMS (or another DBMS) to see if you get any results there.
I want to get the result from a query in my oracle database and put it in a gridview. Now my problem is, I have no idea how to output it in the gridview. I am using the gridview from the toolbox and my oracle connection is working. I also have the right SELECT query and I can output that in a listbox. I just have no idea how to do this in a gridview. I looked for it and I came across this: How to populate gridview with mysql? Although this doesn't help me.
How can I output it in a gridview so that it looks exactly the same as a normal table in the oracle database?
What should I use and how?
This is my code:
public void read()
{
try
{
var conn = new OracleConnection("")
conn.Open();
OracleCommand cmd = new OracleCommand("select * from t1", conn);
OracleDataReader reader = cmd.ExecuteReader();
DataTable dataTable = new DataTable();
while (reader.Read())
{
var column1 = reader["vermogen"];
column = (column1.ToString());
listBox1.Items.Add(column);
}
conn.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
To bind a DataTable to a DataGridView your code need simply to be changed to
public void read()
{
try
{
using(OracleConnection conn = new OracleConnection("....."))
using(OracleCommand cmd = new OracleCommand("select * from t1", conn))
{
conn.Open();
using(OracleDataReader reader = cmd.ExecuteReader())
{
DataTable dataTable = new DataTable();
dataTable.Load(reader);
dataGridView1.DataSource = dataTable;
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
}
The OracleDataReader could be passed to the Load method of the DataTable and then the table is ready to be bound to the DataGridView DataSource property. I have also added some using statement to ensure proper disposing of the disposable objects employed. (In particular the OracleConnection is very expensive to not close in case of exceptions)
You can use DataSet too:
public void read()
{
try
{
OracleConnection conn = new OracleConnection("");
OracleCommand cmd = new OracleCommand("select * from t1", conn);
conn.Open();
cmd.CommandType = CommandType.Text;
DataSet ds = new DataSet();
OracleDataAdapter da = new OracleDataAdapter();
da.SelectCommand = cmd;
da.Fill(ds);
dataGridView1.DataSource = ds.Tables[0];
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
}
First establish connection in case, you didnt establish globally by using connection string. Then use oleDbcommand for the oracle sql command you want to execute. In my case, it is 'select * from table_name' which would show all data from table to datagrid. I wrote this code in a button to display data on data grid.
{
OleDbConnection conn = new OleDbConnection("");
OleDbCommand cmd = new OleDbCommand("select * from table_name", conn);
{
conn.Open();
OleDbDataReader reader = cmd.ExecuteReader();
{
DataTable dataTable = new DataTable();
dataTable.Load(reader);
dataGridView1.DataSource = dataTable;
}
conn.Close();
}
}
I have a data base in SQL Server 2008 and connecting it in WPF application.I want to read data from table and show in datagrid. Connection is successfully created but when I show it in grid,it show db error(Exception handling).
This is what I am doing.Thanks in advance.
try
{
SqlConnection thisConnection = new SqlConnection(#"Server=(local);Database=Sample_db;Trusted_Connection=Yes;");
thisConnection.Open();
string Get_Data = "SELECT * FROM emp";
SqlCommand cmd = new SqlCommand(Get_Data);
SqlDataAdapter sda = new SqlDataAdapter(cmd);
DataTable dt = new DataTable("emp");
sda.Fill(dt);
MessageBox.Show("connected");
//dataGrid1.ItemsSource = dt.DefaultView;
}
catch
{
MessageBox.Show("db error");
}
It shows connected when i comment the line sda.Fill(dt);
Your SqlCommand doesn't know you opened the connection- it requires an instance of SqlConnection.
try
{
SqlConnection thisConnection = new SqlConnection(#"Server=(local);Database=Sample_db;Trusted_Connection=Yes;");
thisConnection.Open();
string Get_Data = "SELECT * FROM emp";
SqlCommand cmd = thisConnection.CreateCommand();
cmd.CommandText = Get_Data;
SqlDataAdapter sda = new SqlDataAdapter(cmd);
DataTable dt = new DataTable("emp");
sda.Fill(dt);
dataGrid1.ItemsSource = dt.DefaultView;
}
catch
{
MessageBox.Show("db error");
}
You don't assign the command any connection. You open the connection then create a command, but don't link the two.
Try something like:
SqlConnection conn = new SqlConnection(#"Server(local);Database=Sample_db;Trusted_Connection=Yes;");
conn.Open();
string sql= "SELECT * FROM emp";
SqlCommand cmd = new SqlCommand(sql);
cmd.Connection = conn;
SqlDataAdapter sda = new SqlDataAdapter(cmd);
DataTable dt = new DataTable("emp");
sda.Fill(dt);
Assign Connection Object to SqlCommand Object.
using (SqlConnection connection = new SqlConnection(
connectionString))
{
SqlCommand command = new SqlCommand();
command.Connection = connection;
command.CommandTimeout = 15;
command.CommandType = CommandType.Text;
command.CommandText = queryString;
connection.Open();
//Perfom desired Action
}
Add thisConnection as 2nd parameter in
Sqlcommand cmd = new SqlCommand(Get_Data, thisConnection)
try {
string connectionstring = "#"
Server = (local) Database = Sample_dbTrusted_Connection = Yes;
"";
SqlConnection thisConnection = new SqlConnection(connectionstring);
thisConnection.Open();
string Get_Data = "SELECT * FROM emp";
SqlCommand cmd = new SqlCommand(Get_Data, thisConnection);
SqlDataAdapter sda = new SqlDataAdapter(cmd);`
DataTable dt = new DataTable("emp");
sda.Fill(dt);
MessageBox.Show("connected");
//dataGrid1.ItemsSource = dt.DefaultView;
} catch {
MessageBox.Show("db error");
}
I use this code with Oracle and hope it will help you.
First add reference Oracle.DataAccess then add namespace using Oracle.DataAccess.Client;
And using the following code
try
{
string MyConString = "Data Source=localhost;User Id= yourusername;Password=yourpassword;";
using (OracleConnection connection = new OracleConnection(MyConString))
{
connection.Open();
sqldb1 = "select * from DEMO_CUSTOMERS;";
using (OracleCommand cmdSe1 = new OracleCommand(sqldb1, connection))
{
DataTable dt = new DataTable();
OracleDataAdapter da = new OracleDataAdapter(cmdSe1);
da.Fill(dt);
db1.ItemsSource = dt.DefaultView;
}
connection.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
XAML code:
<DockPanel>
<DataGrid Margin="10.0" DockPanel.Dock="Left" Name="db1" AutoGenerateColumns="True" >
</DataGrid>
</DockPanel>
public DataTable Execute(string cmd)
{
bool networkUp = System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable();
if (networkUp)
{
try
{
SqlConnection connection = new SqlConnection("ConnectionString");
SqlCommand command = new SqlCommand(cmd);
using (SqlDataAdapter sda = new SqlDataAdapter())
{
DataTable dt = new DataTable();
sda.SelectCommand = command;
command.Connection = connection;
connection.Open();
sda.Fill(dt);
connection.Close();
if (dt != null && dt.Columns.Count > 0)
return dt;
else
return null;
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
return null;
}
}
else
{
Console.WriteLine("Network is disconnect");
return null;
}
return null;
}
or :
public void ExecuteNonQuery(string cmd)
{
bool networkUp = System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable();
if (networkUp)
{
try
{
SqlConnection connection = new SqlConnection("ConnectionString");
SqlCommand command = new SqlCommand(cmd);
command.Connection = connection;
connection.Open();
command.ExecuteNonQuery();
connection.Close();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
I'm having a problem running a query across multiple databases on an Azure SQL Server. This is the function I have made to return a DataTable from the query once it has been executed. The function takes the database name as a string and inserts it into the conenction string, along with the query to be executed.
The function works fine when I run it once, returning the DataTable populated with returned rows as intended, but when I call the function using a 'foreach' statement (Iterating through a list of database names) I get a timeout error or a login failed error.
Any help on this would be appreciated.
public static DataTable runQuery(String db, String query)
{
using (SqlConnection con = new SqlConnection("Data Source=server.database.windows.net;Initial Catalog=" + db + ";User ID=user#server;Password=password"))
{
con.Open();
using (DataTable dt = new DataTable())
{
try
{
SqlCommand cmd = new SqlCommand(query, con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(dt);
cmd.Dispose();
da.Dispose();
}
catch (SqlException ex)
{
MessageBox.Show(ex.Message);
}
return dt;
}
}
}
Add cmd.CommandTimeout = 0
try
{
SqlCommand cmd = new SqlCommand(query, con);
cmd.CommandTimeout = 0;
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(dtt);
cmd.Dispose();
da.Dispose();
}
I think you should try adding System.Threading.Thread.Sleep inside the foreach block.