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C# Parameterized query - parameters not being replaced with set value

I'm passing a query and parameter from a WinForm to a database class. The
The code on the Form looks like this:
string selectedComp = "CPSI";
string catsQuery = "SELECT id, category, old_value, old_desc, new_value, new_desc, reference1, reference2 FROM masterfiles.xref WHERE company_name = '#company' ORDER BY category, old_value";
Db categoriesData = new Db();
dgvCategories.DataSource = categoriesData.GetData(catsQuery, selectedComp);
And in my database class my code to populate the datatable/set is this:
public DataTable GetData(string selectQuery, string selectedComp)
{
NpgsqlConnection conn = new NpgsqlConnection(connString);
DataSet ds = new DataSet();
NpgsqlCommand cmd = new NpgsqlCommand(selectQuery, conn);
cmd.Parameters.Add(new NpgsqlParameter("#company", selectedComp));
//cmd.Parameters.AddWithValue("#company", selectedComp);
//cmd.Parameters.Add("#company", NpgsqlDbType.Text);
//cmd.Parameters["#company"].Value = selectedComp;
try
{
conn.Open();
NpgsqlDataAdapter da = new NpgsqlDataAdapter(selectQuery, conn);
conn.Close();
da.Fill(ds);
return ds.Tables[0];
}
}
But putting a breakpoint at NpgsqlDataAdapter da = new NpgsqlDataAdapter(selectQuery, conn);, selecctQuery hasn't changed - the '#company' is still in the query.
What am I missing?

The root problem is that you're passing the query to the data adapter instead of the command. Change
NpgsqlDataAdapter da = new NpgsqlDataAdapter(selectQuery, conn);
to
NpgsqlDataAdapter da = new NpgsqlDataAdapter(cmd);
I would also use using to dispose of all objects, and don't close the connection until the dataset is filled:
using(NpgsqlConnection conn = new NpgsqlConnection(connString))
using(NpgsqlCommand cmd = new NpgsqlCommand(selectQuery, conn))
{
cmd.Parameters.Add(new NpgsqlParameter("company", selectedComp));
conn.Open();
using(NpgsqlDataAdapter da = new NpgsqlDataAdapter(cmd))
{
DataSet ds = new DataSet();
da.Fill(ds);
}
conn.Close();
return ds.Tables[0];
}

Error when Using queryString

when I try to get the Url and pass it to procedure
it didn't passed
string ID = Request.QueryString["URL"];
youtube y = new youtube();
y.URL = ID;
repCurrentVideo.DataSource = y.CurrentVideo();
repCurrentVideo.DataBind();
lblDetails.Text = "no details available about this video";
an error shown to me said
Procedure or function 'currentvideo' expects parameter '#URL', which was not supplied.
Exception Details: System.Data.SqlClient.SqlException: Procedure or function 'currentvideo' expects parameter '#URL', which was not supplied.
and this is the stored procedure invoking code
public DataTable CurrentVideo()
{
CreateConnection();
SqlCommand cmd = new SqlCommand();
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#URL", URL);
SqlDataAdapter da = new SqlDataAdapter("currentvideo", conn);
DataTable dt = new DataTable();
da.Fill(dt);
return dt;
}

You are never adding the SqlCommand (cmd) to your data adapter
try something like this:
cmd.Parameters.AddWithValue("#URL", URL);
da.SelectCommand = cmd;
or
CreateConnection();
SqlCommand cmd = new SqlCommand("currentvideo", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#URL", URL);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
return dt;
Also, while we are on the topic of SqlCommands, I believe it is best to wrap them in a using statement as they are of type IDisposable.
using (SqlCommand command = new SqlCommand("currentvideo", conn)) {
...
}
Check out this link to see what it looks like:
http://www.dotnetperls.com/sqlcommand
Edit:
So based on your URL, you are looking for the wrong query string parameter. You need to change the assignment of ID to this:
string ID = Request.QueryString["ID"];

Error CS0103 FastReport.net

i am C#.net Windows Form developer .
i am using FastReport.net . but have some error .
this is my code :
DataSet ds = new DataSet();
SqlConnection cnn = new SqlConnection("MyCnnStr");
SqlCommand cmd = new SqlCommand();
cmd.Connection = cnn;
cmd.CommandText = "select * from test";
cmd.CommandType = CommandType.Text;
SqlDataAdapter dap = new SqlDataAdapter(cmd);
dap.Fill(ds, "ds");
report1.RegisterData(ds.Tables[0],"ds");
report1.GetDataSource("ds").Enabled = true;
report1.Load("Untitled.frx");
report1.Show();
but my error :
what is my wrong ?

If name, tel and fax is names of tables, then you can try to write following:
DataSet ds = new DataSet();
SqlConnection cnn = new SqlConnection("MyCnnStr");
SqlCommand cmd = new SqlCommand();
cmd.Connection = cnn;
cmd.CommandText = "select * from test";
cmd.CommandType = CommandType.Text;
SqlDataAdapter dap = new SqlDataAdapter(cmd);
dap.Fill(ds, "ds");
report1.RegisterData(ds.Tables[0],"ds");
report1.GetDataSource("ds").Enabled = true;
report1.GetDataSource("name").Enabled = true; // add this part
report1.GetDataSource("tel").Enabled = true; //
report1.GetDataSource("fax").Enabled = true; //
report1.Load("Untitled.frx");
report1.Show();
Also you can try delete connections in Designer mode.

CS0103 may appear if you casually print symbol from other keyboard layout.
For example: E (English), Е (Russian), Ε (Greek).

Want to show data from two different tables in two different datagridviews in a form in c#

I have two different queries for two different tables I want to show the result in two datagridviews on a form
string query1 = string.Format("select * from Flat where [Flat_No.]='{0}'",flat.Text);
string query2 = string.Format("select * from 1");
SqlCommand cmd = new SqlCommand(query1, con);
SqlCommand cmd1 = new SqlCommand(query2, con1);
dataview frm1 = new dataview(query1,query2); //the form where data is to be displayed
// on form dataview I have two DataGridViews
public dataview(string a,string b)
{
InitializeComponent();
SqlConnection con = new SqlConnection(Class1.getConnectionString);
//connection name
con.Open();
SqlCommand cmd = new SqlCommand(a , con);
cmd.CommandType = CommandType.Text;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds, "ss");
dataGridView1.DataSource = ds.Tables["ss"];
con.Close();
SqlConnection con1 = new SqlConnection(Class1.getConnectionString);
//connection name for query1
con1.Open();
SqlCommand cmd1 = new SqlCommand(b, con1);
cmd1.CommandType = CommandType.Text;
SqlDataAdapter da1 = new SqlDataAdapter(cmd1);
DataSet ds1 = new DataSet();
da.Fill(ds1, "aa");
dataGridView2.DataSource = ds1.Tables["aa"];
con1.Close();
}
}
but the above code is showing data from query 1 in both the datagridviews. plz help me out how can I solve this problem? If there in another way let me know it also. I have also tried to merge both the queries using "+" sign but it also didn't proved helpful.

Use da1.Fill instead of da.fill. You're using the da DataAdapter for filling both Datasets
da.Fill(ds1, "aa");
da1.Fill(ds1, "aa");

How to get data from SQL database to store in combo box - C#

How can i get the value of company_name from Comp table and store it on a comboBox?
here is my initial code on getting the values from Database and store it on a combobox:
string Sql = "select company_name from JO.dbo.Comp";
SqlConnection conn = new SqlConnection(connString);
SqlCommand cmd = new SqlCommand(Sql, conn);
cmd.CommandType = CommandType.StoredProcedure;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
comboBox1.Items.Add(ds.Tables[0].Rows[i][0].ToString());
it point out to da.fill(ds) and says "Could not locate entry in sysdatabases for database 'select company_name from JO'. No entry found with that name. Make sure that the name is entered correctly."
hope for your reply thanks!

Use datareader it is much simpler \
string Sql = "select company_name from JO.dbo.Comp";
SqlConnection conn = new SqlConnection(connString);
conn.Open();
SqlCommand cmd = new SqlCommand(Sql, conn);
SqlDataReader DR = cmd.ExecuteReader();
while (DR.Read())
{
combobox1.Items.Add(DR[0]);
}

If you set up your connection string to be something of this sort:
string SqlConnectionString = "Data Source=[SERVER];Initial Catalog=[DATABASE];"
Then using that set up, you can set your string 'Sql' as:
string Sql = "select company_name from dbo.Comp";
This could be a possible set up you could use to read out the values.
using (SqlConnection saConn = new SqlConnection(this.ConnectionString))
{
saConn.Open();
string query = "select DBName from dbo.Company";
SqlCommand cmd = new SqlCommand(query, saConn);
using (SqlDataReader saReader = cmd.ExecuteReader())
{
while (saReader.Read())
{
string name = saReader.GetString(0);
combobox1.Add(name);
}
}
saConn.Close();
}

I would like to introduce you a very simple way to SQL data into a combobox as:
first you have a create a SQL table,
in C# platform drop a combobox and go to its property,
in the property menu click on "DataSource"
specify the database and table to load into combobox,
Note, the combobox name and table's row should be the same.

{
SqlConnection con =new SqlConnection("Data Source=Server_Name;Initial Catalog=Database_Name;integrated security=true");
SqlCommand cmd;
SqlDataReader dr;
private void CashMemoForm_Load(object sender, EventArgs e)
{
con.Open();
cmd = new SqlCommand("Select Column_Name From Table_Name", con);
dr = cmd.ExecuteReader();
while (dr.Read())
{
comboBox1.Items.Add(dr[0]).ToString();
}
}
}

Have you ever tried Entity Framework for database access and dto creation?

Change your line to cmd.CommandType = CommandType.Text; instead of cmd.CommandType = CommandType.StoredProcedure;

Try this
string Sql = "select Company_ID,company_name from JO.dbo.Comp";
SqlConnection conn = new SqlConnection(connString);
SqlCommand cmd = new SqlCommand(Sql, conn);
cmd.CommandType = CommandType.Text;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
{
comboBox1.DataSource = ds.Tables[0];
comboBox1.DataTextField = "company_name";
comboBox1.DataValueField = "Company_ID";
comboBox1.DataBind();
comboBox1.Items.Insert(0, new ListItem("--Select--", "0"));
}

There is no use of for loop. you just need to check that whether the dataset contains rows or not.
string Sql = "select Company_ID,company_name from JO.dbo.Comp";
SqlConnection conn = new SqlConnection(connString);
SqlCommand cmd = new SqlCommand(Sql, conn);
cmd.CommandType = CommandType.Text;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
if (ds.Tables[0].Rows.Count > 0)
{
comboBox1.DataSource = ds.Tables[0];
comboBox1.DataTextField = "company_name";
comboBox1.DataValueField = "Company_ID";
comboBox1.DataBind();
comboBox1.Items.Insert(0, new ListItem("Select", "0"));
}

string Sql = "select company_name from JO.dbo.Comp";
SqlConnection conn = new SqlConnection(connString);
SqlCommand cmd = new SqlCommand(Sql, conn);
cmd.CommandType = CommandType.StoredProcedure;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
comboBox1.Items.Add(ds.Tables[0].Rows[i][0].ToString());

public System.Data.DataTable EmployeeViewAll()
{
DataTable dtbl = new DataTable();
try
{
// Here it shuld be your database Connection String
string connectionString = "Server = .; database = HKS; Integrated Security = true";
using (SqlConnection sqlCon = new System.Data.SqlClient.SqlConnection(connectionString))
{
SqlDataAdapter SqlDa = new SqlDataAdapter("employeeViewAll", sqlCon);
SqlDa.SelectCommand.CommandType = CommandType.StoredProcedure;
SqlDa.Fill(dtbl);
}
return dtbl;
}
catch (Exception)
{
throw;
}
}
public void ComboFill()
{
DataTable dt = new DataTable();
eSP SP = new eSP();
d = SP.EmployeeViewAll();
comboBox1.DataSource = dt;
comboBox1.DisplayMember = "department";
comboBox1.ValueMember = "empName";
}