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asp.net c# Stored procedure, when passing parameter, its not working, just raw coding the value at line 31 any solution?

protected void Getbooks()
{
SqlConnection con = new SqlConnection(strConnString);
con.Open();
//call shopping cart procedure
SqlCommand command = new SqlCommand("ShoppingCartGetItems", con);
//How To pass value here instead of raw coding value if cartid 3?
command.Parameters.AddWithValue("#cartid", 3);
command.CommandType = CommandType.StoredProcedure;
SqlDataAdapter da = new SqlDataAdapter(command);
DataTable dt = new DataTable();
da.Fill(dt);
gridcart.DataSourceID = null;
gridcart.DataSource = dt;
gridcart.DataBind();
}

using System;
using System.Data;
using System.Data.SqlClient;
class StoredProcDemo
{
static void Main()
{
StoredProcDemo spd = new StoredProcDemo();
// run a simple stored procedure
spd.RunStoredProc();
// run a stored procedure that takes a parameter
spd.RunStoredProcParams();
}
// run a simple stored procedure
public void RunStoredProc()
{
SqlConnection conn = null;
SqlDataReader rdr = null;
Console.WriteLine("\nTop 10 Most Expensive Products:\n");
try
{
// create and open a connection object
conn = new
SqlConnection("Server=(local);DataBase=Northwind;Integrated Security=SSPI");
conn.Open();
// 1. create a command object identifying
// the stored procedure
SqlCommand cmd = new SqlCommand(
"Ten Most Expensive Products", conn);
// 2. set the command object so it knows
// to execute a stored procedure
cmd.CommandType = CommandType.StoredProcedure;
// execute the command
rdr = cmd.ExecuteReader();
// iterate through results, printing each to console
while (rdr.Read())
{
Console.WriteLine(
"Product: {0,-25} Price: ${1,6:####.00}",
rdr["TenMostExpensiveProducts"],
rdr["UnitPrice"]);
}
}
finally
{
if (conn != null)
{
conn.Close();
}
if (rdr != null)
{
rdr.Close();
}
}
}
// run a stored procedure that takes a parameter
public void RunStoredProcParams()
{
SqlConnection conn = null;
SqlDataReader rdr = null;
// typically obtained from user
// input, but we take a short cut
string custId = "FURIB";
Console.WriteLine("\nCustomer Order History:\n");
try
{
// create and open a connection object
conn = new
SqlConnection("Server=(local);DataBase=Northwind;Integrated Security=SSPI");
conn.Open();
// 1. create a command object identifying
// the stored procedure
SqlCommand cmd = new SqlCommand(
"CustOrderHist", conn);
// 2. set the command object so it knows
// to execute a stored procedure
cmd.CommandType = CommandType.StoredProcedure;
// 3. add parameter to command, which
// will be passed to the stored procedure
cmd.Parameters.Add(
new SqlParameter("#CustomerID", custId));
// execute the command
rdr = cmd.ExecuteReader();
// iterate through results, printing each to console
while (rdr.Read())
{
Console.WriteLine(
"Product: {0,-35} Total: {1,2}",
rdr["ProductName"],
rdr["Total"]);
}
}
finally
{
if (conn != null)
{
conn.Close();
}
if (rdr != null)
{
rdr.Close();
}
}
}
}

ODP.NET Implement Cursor for SELECT statement

How can I implement a simple cursor fetch on a basic SELECT statement like 'SELECT * FROM Employees' using ODP.NET?

So it's quite straightforward.
First create OracleConnection class like this
OracleConnection con = new OracleConnection(ConfigurationManager.ConnectionStrings["connectionstring"].ConnectionString);
con.Open(); //opens connection
Then you define and OracleCommand instance first by passing either raw query/stored procedure as first argument like
So in your particular case it would be OracleCommand cmd = new OracleCommand("SELECT * FROM Employees", con
if (con.State == ConnectionState.Open)
{
using (OracleCommand cmd = new OracleCommand(<query>/<stored proc>, con))
{
cmd.CommandType = CommandType.StoredProcedure; //in case of stored proc
cmd.BindByName = true;
OracleDataReader reader;
try
{
reader = cmd.ExecuteReader();
while(reader.Read())
{
Console.WriteLine("field: {0}", reader.GetDecimal(0));
}
}
catch (OracleException e)
{
foreach (OracleError err in e.Errors)
{
//print errors
}
}
con.Close();
con.Dispose();
}
}
Here is the example http://www.oracle.com/technetwork/articles/dotnet/williams-refcursors-092375.html

C# SQL, Multiple Commands

I'm trying to write a method which should communicate with database, but I'm not sure if my approach is right.
public void dbWorkerLogin(int workerNumber) {
// Connection string stored in "conn"
if (!new SqlCommand("Some Command WHERE id=" +workernumber,conn).executeReader().HasRows)
{
new SqlCommand("exec STORED_PROCEDURE1 " + workerNumber, conn).ExecuteNonQuery();
new SqlCommand("exec STORED_PROCEDURE2 " + workerNumber, conn).ExecuteNonQuery();
}
else
{
new SqlCommand("exec STORED_PROCEDURE3 " + workerNumber,conn).ExecuteNonQuerry();
}
1) Is it ok to write it like this and start each SqlCommand with keyword new? Or should I do something like:
SqlCommand command = new SqlCommand(null, conn);
command = ...;
and then recycle the variable 'command' or this way?
using(SqlCommand cmd = new SqlCommand("COMMAND", conn);
2) Will my procedures work or should I use SqlCommand.Prepare() function that will covert my data into correct datatypes? eg. workerNumber is int, but in database it is stored as decimal.
using (SqlCommand cmd = new SqlCommand("STORED_PROCEDURE", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parametres.Add("#id", SqlDbType.Decimal).Value = workNumber;
cmd.Prepare();
cmd.ExecuteNonQuery();
}
Can you please somehow sum up what to use, what better not to? Unfortunately I can't test that first code because of limited access to DB so I'm not sure if it can be executed without errors or not.
Thank you for any help on this subject!
EDIT:
After a few hours I reach to this stage:
public int getWorkerNumber(string uniqueID)
{
using (conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbConnect"].ConnectionString))
{
conn.Open();
using (SqlCommand cmd = new SqlCommand("SELECT number FROM worker WHERE workerID = #id",conn))
{
cmd.Parameters.Add("#id", SqlDbType.Decimal).Value = uniqueID;
using (SqlDataReader reader = cmd.ExecuteReader())
{
int answer;
while (reader.Read())
{
answer = (int)reader.GetDecimal(0);
}
return answer;
}
}
}
}
And this one:
public string dbLoginWorker(int workerNumber)
{
SqlCommand cmd;
SqlDataReader reader;
using (conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbConnect"].ConnectionString))
{
conn.Open();
cmd = new SqlCommand("SELECT column FROM table WHERE id= #workernumber", conn);
cmd.Parameters.Add("#workernumber", SqlDbType.Decimal).Value = workerNumber;
reader = cmd.ExecuteReader();
if (!reader.HasRows)
{
cmd = new SqlCommand("STORED_PROCEDURE1", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal).Value = workerNumber;
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar).Value = "text";
cmd.Prepare();
reader.Close();
cmd.ExecuteNonQuery();
cmd.Dispose();
reader.Dispose();
return "procedure 1 executed";
else
{
cmd = new SqlCommand("STORED_PROCEDURE2", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal).Value = workerNumber;
cmd.Parameters.Add("#INT", SqlDbType.SmallInt).Value = 1;
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar).Value = "text";
cmd.Prepare();
reader.Close();
cmd.ExecuteNonQuery();
cmd.Dispose();
reader.Dispose();
return "procedure 2 executed";
}
}
}
Both methods are functional (if I did no mistake in rewriting :) ). I'm not sure which of these methods (1st or 2nd) are better in terms of stability and if this approach is better and more ressistant to SQL Injection. Can someone comment on this subject? Thank you again for any help!

1) It is best to always use USING blocks when possible. This includes SqlConnection, SqlCommand, SqlReader and other objects that implement IDisposable. USING blocks automatically close and dispose of the objects, so you do not have to do so.
2) I believe that you are using the Prepare() method in the wrong place. Look at the following StackOverflow article for proper usage:
PrepareMethodInstructions.
3) in the dbLoginWorker() method, the first query is just used to determine if rows are found. Therefore, I suggest changing the SELECT command to SELECT TOP 1 column FROM table WHERE id= #workernumber so that the query is faster and more efficient.
4) I do not believe your commands are subject to SQL Injection attacks because they are fully parameterized. Good job on that one.
5) As a general thought, I suggest reading up on refactoring techniques. Your dbLoginWorker() method could be made more readable and maintainable, as well as self-documenting, if you created three additional methods, one for each SQL command, and named them something appropriate. You could also setup a method for creating a connection based on a connection name, and you would not have as much duplicate code. For example:
public static SqlConnection GetConnection(string connectionName)
{
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings[connectionName].ConnectionString);
conn.Open();
return conn;
}
public string dbLoginWorker(int workerNumber)
{
using (conn = GetConnection("dbConnect"))
{
if (CanFindWorkerNumber(conn, workerNumber))
ExecuteProcedure1(conn);
else
ExecuteProcedure2(conn);
}
}
public bool CanFindWorkerNumber (SqlConnection conn, int workerNumber)
{
bool success = false;
using (SqlCommand cmd = new SqlCommand("SELECT TOP 1 column FROM table WHERE id= #workernumber", conn))
{
cmd.Parameters.Add("#workernumber", SqlDbType.Decimal);
cmd.Prepare();
cmd.Parameters[0].Value = workerNumber;
success = cmd.ExecuteScalar() != null;
}
return success;
}
public void ExecuteProcedure1(SqlConnection conn)
{
using (SqlCommand cmd = new SqlCommand("STORED_PROCEDURE1", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal);
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar);
cmd.Prepare();
cmd.Parameters[0].Value = workerNumber;
cmd.Parameters[1].Value = "text";
cmd.ExecuteNonQuery();
}
}
public void ExecuteProcedure1(SqlConnection conn)
{
using (SqlCommand cmd = new SqlCommand("STORED_PROCEDURE1", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal);
cmd.Parameters.Add("#INT", SqlDbType.SmallInt).Value);
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar);
cmd.Prepare();
cmd.Parameters[0] = workerNumber;
cmd.Parameters[1] = 1;
cmd.Parameters[2] = "text";
cmd.ExecuteNonQuery();
}
}

You could actually do this in one SQL commend. Right now you are pulling back a result set only to see if it has rows or not, then executing different commands based on that. You should be able to do that in one command, disposing of it and the connection appropriately:
var sql =
#"
IF EXISTS(Some Command WHERE id=#workernumber)
BEGIN
exec STORED_PROCEDURE1 #workernumber;
exec STORED_PROCEDURE2 #workernumber;
END
ELSE
exec STORED_PROCEDURE3 #workernumber;
";
Note that you're not vulnerable to SQL injection because you're not dealing with strings, only integers.

Stored procedure has no parameters and arguments were supplied

I have a function which will get the records from the database.
public List<Issue> Load_Issues()
{
SqlDataReader Sdr;
List<Issue> ObjList = new List<Issue>();
cmd.CommandText = "Get_All_Issue";
try
{
cmd.Connection = con;
cmd.CommandType = CommandType.StoredProcedure;
con.Open();
Sdr = cmd.ExecuteReader();
while (Sdr.Read())
{
// here I pull out records from database..
}
}
catch (Exception ex)
{
throw ex;
}
finally
{
con.Close();
}
return ObjList;
}
The function I am using to bind the Gridview is as follows
public void Bind_Issues()
{
gdIssues.DataSource = Bl.Load_Issues()();
gdIssues.DataBind();
}
My stored procedure doesn't take any arguments. While the page loads for the first time it is working fine and binding the records to the gridview.
We have option to edit the records also, so what happening is after updating records I need to again bind the records to gridview. So I am again using my Load_Issues function to do it. But this time it is throwing error
Get_All_Issues has no parameters and arguments were supplied

You're most probably re-using the cmd instance in multiple places and you don't clear the parameters associated with it, thus creating the exception you're seeing.
Easiest fix would be to not re-use cmd, but if for whatever reason it's better for you, just make sure you use Clear on parameters before you execute it.
cmd.Parameters.Clear();

Try not using global connections, commands etc: open and close them within the method
public List<Issue> Load_Issues() {
//TODO: Put actual connection string here
using (SqlConnection con = new SqlConnection("Connection String here")) {
con.Open();
// Put IDisposable into using
using (SqlCommand cmd = new SqlCommand()) {
cmd.Connection = con;
cmd.CommandText = "Get_All_Issue";
cmd.CommandType = CommandType.StoredProcedure;
List<Issue> ObjList = new List<Issue>();
// Put IDisposable into using
using (var Sdr = cmd.ExecuteReader()) {
while (Sdr.Read()) {
//TODO: Pull out records from database into ObjList
}
}
return ObjList;
}
}
}

Try these
exec 'stored_procedure_name'
go
or
alter proc stored_procedure_name
as
begin
--Block of Statements
end
go
or
create proc stored_procedure_name
as
begin
--Block of Statements
end
go
Where go keyword will solved your problem.

Getting "Invalid attempt to call Read when reader is closed"

I've got the following code (here with pseudovalues for readability), where the first connection returns a lot of data (thousands of rows). SqlDataReader reads them one by one by the reader.Read() and then opens a new connection to update each row with new values:
using (SqlConnection conn = new SqlConnection(connString))
using (SqlCommand cmd = new SqlCommand("sp1", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#param1", param1);
cmd.Connection.Open();
using (SqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
try
{
string hash= utils.SHA256.Hashing((string)reader["firstRow"], saltValue);
using (SqlConnection conn2 = new SqlConnection(connString))
using (SqlCommand cmd2 = new SqlCommand("sp2", conn2))
{
cmd2.CommandType = CommandType.StoredProcedure;
cmd2.Parameters.AddWithValue("#param1", param1);
cmd2.Parameters.AddWithValue("#param2", param2);
cmd2.Connection.Open();
cmd2.ExecuteNonQuery();
}
}
catch (SqlException ex)
{
//something
}
}
}
}
but it throws an error:
[InvalidOperationException: Invalid attempt to call Read when reader is closed.]
System.Data.SqlClient.SqlDataReader.ReadInternal(Boolean setTimeout) +640
System.Data.SqlClient.SqlDataReader.Read() +9
In development environment it works fine, but here there's only a few hundred rows. It throws the error immediately, so it doesn't directly look like some kind of timeout, but hey - I don't know...

Don't know why it happens, but it's really a bad idea to execute queries while iterating a live connection to the same database. Keep in mind that as long as you iterate records with a DataReader, the connection is alive.
Much worse is opening then closing a connection thousands of times in a quick succession. This alone can bring any database down to its knees.
Change your logic, store the values you need in a local variable (structure doesn't matter) then use one connection only to execute all the stored procedures you need.
For example:
using (SqlConnection conn = new SqlConnection(connString))
{
conn.Open();
List<string[]> values = new List<string[]>();
using (SqlCommand cmd = new SqlCommand("sp1", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#param1", param1);
using (SqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
try
{
string hash= utils.SHA256.Hashing((string)reader["firstRow"], saltValue);
string anotherValue = (string)reader["secondRow"];
values.Add(new string[] { hash, anotherValue });
}
catch (SqlException ex)
{
//something
}
}
reader.Close();
}
}
if (values.Count > 0)
{
using (SqlCommand cmd2 = new SqlCommand("sp2", conn))
{
cmd2.CommandType = CommandType.StoredProcedure;
cmd2.Parameters.AddWithValue("#param1", null);
cmd2.Parameters.AddWithValue("#param2", null);
values.ForEach(items =>
{
cmd2.Parameters["#param1"].Value = items[0];
cmd2.Parameters["#param2"].Value = items[1];
cmd2.ExecuteNonQuery();
});
}
}
conn.Close();
}
One connection, one command to execute all stored procedures. Really don't need more than that.