Develop Reference

Inserting data into a MS Access database

try
{
OleDbConnection myConnection = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Users\\HP8200\\Desktop\\ELISA2014Data.mdb ;Persist Security Info=False;");
myConnection.Open();
// Create Oledb command to execute particular query
OleDbCommand myCommand = new OleDbCommand();
myCommand.Connection = myConnection;
// Query to create table with specified data columne
myCommand.CommandText = "CREATE TABLE UXZona([IDZona] int, [Morada] text)";
//myCommand.ExecuteNonQuery();
MessageBox.Show("Tabela criada");
}
catch
{
OleDbConnection myConnection = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Users\\HP8200\\Desktop\\ELISA2014Data.mdb ;Persist Security Info=False;");
myConnection.Open();
OleDbCommand cmd = new OleDbCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "INSERT INTO UXZona (IDZona, Morada) VALUES ('" +
transaction.UnloadPlaceAddress.AddressID + "','" +
transaction.UnloadPlaceAddress.AddressLine2 + "')";
cmd.ExecuteNonQuery();
MessageBox.Show("Dados inseridos");
}
I need to insert data into the database but it isn't working. I launch the program and there are no errors, I do everything but when I check the database the table is empty.
UPDATE
Now when i launch the program I have this error:
"System.InvalidOperationException: 'ExecuteNonQuery: Connection property has not been initialized." on cmd.ExecuteNonQuery();

There are a number of things wrong! I give below corrected code:
try
{
bool success = false;
using (var myConnection = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Users\\HP8200\\Desktop\\ELISA2014Data.mdb ;Persist Security Info=False;"))
{
// Create Oledb command to execute particular query
using (var myCommand = new OleDbCommand())
{
myCommand.Connection = myConnection;
// Query to create table with specified data columne
//myCommand.CommandText = "CREATE TABLE UXZona([IDZona] int, [Morada] text)";
//myCommand.ExecuteNonQuery();
//MessageBox.Show("Tabela criada");
cmd.CommandType = CommandType.Text;
cmd.CommandText = "INSERT INTO UXZona (IDZona, Morada) VALUES (#id, #morada)";
var param = cmd.CreateParameter();
param.ParameterName = "#id";
param.OleDbType = OleDbType.Integer;
param.Value = transaction.UnloadPlaceAddress.AddressID;
cmd.Parameters.Add(param);
param = cmd.CreateParameter();
param.ParameterName = "#morada";
param.OleDbType = OleDbType.VarChar;
param.Value = transaction.UnloadPlaceAddress.AddressLine2;
cmd.Parameters.Add(param);
myConnection.Open();
if (cmd.ExecuteNonQuery() == 1)
{
success = true;
}
}
}
if (success)
{
MessageBox.Show("Dados inseridos");
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
By way of explanation. I have commented out (but not deleted) all references to creating the table. Table creation and table insertion should be in two different routines. Normally you only create a table once, but insert is probably called many times.
I have placed the OleDbConnection and OleDbCommand within using loops. This is good practice, as they both implement IDisposable. Writing your code like this means that the Garbage Collector (GC) knows immediately that it can safely dispose of the objects after use.
I have changed the insert statement such that it takes parameters. This is highly recommended practice to safeguard against SQL Injection (if you do not know what this is please Google it). In fact Access is relatively immune from the worst forms of SQL Injection, because it rejects any command that contains multiple statements, but please get into good habits. With time you will progress to other databases which do not have this restriction.
I deliberately wait before opening the connection until just before it is needed. Connections consume resources, so it is good practice to use them as sparingly as possible. Also for this reason, I have moved your success message outside of the using loops. This means that the cleanup of resources is not waiting for the user to click OK in the message box.
Finally try catch is all well and good, but normally you want to know why the error occurred. Hence you add (Exception ex) to catch so that you can find the reason.
PS What I forgot to mention. In your original INSERT, you were surrounding both VALUES with single quotes. Only use single quotes for strings/text. Integers and other numbers require no quotes. If you quote them, the database will treat it as a string and you will get a data type error.

Insert into Access Database on button click

i'm still new in c# programing ,is any one can help me to solve this error coming when i try to add a data in database but error comes after this line command.ExecuteNonQuery();
private void button1_Click(object sender, EventArgs e)
{
string constr = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\aberto\Documents\esimar_db.accdb;Persist Security Info=False;";
string cmdstr = "insert into employee(employee_name, location,connection,depanse,caisse)values(#employee_name,#location,#connection,#depanse,#caisse)";
OleDbConnection connect = new OleDbConnection(constr);
OleDbCommand command = new OleDbCommand(cmdstr, connect);
connect.Open();
command.Parameters.AddWithValue("#employee_name", textBox1.Text);
command.Parameters.AddWithValue("#location", comboBox1.Text);
command.Parameters.AddWithValue("#connection", textBox2.Text);
command.Parameters.AddWithValue("#depanse", textBox3.Text);
command.Parameters.AddWithValue("#printing", textBox4.Text);
command.Parameters.AddWithValue("#caisse", textBox5.Text);
command.ExecuteNonQuery();
MessageBox.Show( "Record saved successfully");
connect.Close();
}

CONNECTION is reserved word in Access SQL so you have to enclose it in square brackets if it is to be used as a column (or table) name:
string cmdstr =
"insert into employee(employee_name, location, [connection], depanse, caisse) values (#employee_name, #location, #connection, #depanse, #caisse)";
Also, be aware that your CommandText only has five (5) parameters in it, but you have six (6) Parameters.AddWithValue statements. OleDb ignores parameter names and only pays attention to the order in which the parameters are declared, so only the first five (5) of those statements will have any effect.

C# ADO.NET - Could Not Find Stored Procedure

I am trying to execute a stored procedure through C#, ADO.NET and below is the code I am trying to execute:
using (SqlConnection conn = new SqlConnection(".;Initial Catalog=MyDB;User ID=sa;Password=***"))
{
try
{
string cmdText = "dbo.sp_Create_FlaggedItemEntry #URI, #ID";
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
conn.Open();
cmd.CommandText = cmdText;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#URI", value1);
cmd.Parameters.AddWithValue("#ID", value2);
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (conn != null)
{
conn.Close();
}
}
}
Now when I try to debug it, I got an error at the line - cmd.ExecuteNonQuery(); - "Could Not Find Stored Procedure dbo.sp_Create_FlaggedItemEntry"
I verified that the Connection String is all correct and Stored Procedure exists.
Further, If I change the line - cmd.CommandType = CommandType.StoredProcedure; to cmd.CommandType = CommandType.Text; it get executed successfully and as expected.
Can someone suggest what I am missing and doing wrong here - Please pardon me if it is something very basic as it is quite long since I last worked with ADO.NET

CommandType.StoredProcedure means that the CommandText should only contain the name of the stored procedure.
Remove the parameter names from the string.

Take the parameters out of the command text. Also, you don't need to specify dbo.
The reason it's working with CommandType.Text is because it's a legitimate SQL command like that - if you were to open up SSMS and type that in it'd work as long as you also create the variables #URI and #ID
Documentation here

You should mention Data Source / Server in connectionString. Also for CommandText #Slaks is correct.

c# register form mysql insert

So im having problem gettin some data in to the database.. Im really stuck, im quite new to c# and have not learned all keywords yet, im not getting any errors just some nothing adds to my database.
textBox2.Text = myPWD;
MySqlConnection conn = new MySqlConnection("test")
string Query = "INSERT INTO `users`.`coffekeys` (`koffekeys`) VALUES ('values = #val')";
MySqlCommand data = new MySqlCommand(Query, conn);
MySqlDataReader myReader;
conn.Open();
SelectCommand.Parameters.AddWithValue("#val", this.textBox2.Text);
conn.Closed()

Manipulate the concatenation of value in passing of parameters. Don't do it inside sql statement.
string Query = "INSERT INTO `users`.`coffekeys` (`koffekeys`) VALUES (#val)";
// other codes
SelectCommand.Parameters.AddWithValue("#val", "values = " + this.textBox2.Text);
the reason why the parameter is not working is because it was surrounded by single quotes. Parameters are identifiers and not string literals.
The next problem is you did not call ExecuteNonQuery() which will execute the command.
Before closing the connection, call ExecuteNonQuery()
// other codes
data.ExecuteNonQuery();
conn.Close();

You should Google around and you will receive lots of content
You need to run ExecuteNonQuery
SqlConnection con = new SqlConnection(constring);
con.Open();
SqlCommand cmd = new SqlCommand(
"insert into st (ID,Name) values ('11','seed');", con);
cmd.ExecuteNonQuery();
cmd.Close();

Question in error in asp.net c#

i have a question if you please help me i have an error
Must declare the scalar variable
"#Deitails".
and i can not find out whats the problem since i am not aware what Scalar is about
var sqlCon = new
SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);
// GET CONFERENCE ROLE ID
SqlCommand cmd = new SqlCommand();
cmd.Connection = sqlCon;
cmd.CommandText = "select Conference_Role_ID from AuthorPaper
where Paper_ID = #PaperId";
cmd.Parameters.AddWithValue("#PaperId",
paperId);
cmd.Connection.Open();
string ConferenceRoleId = cmd.ExecuteScalar().ToString();
cmd.Connection.Close();
cmd.Dispose();
string query2 = #"insert into
ReviewPaper(Overall_Rating,Paper_id,Conference_role_id,Deitails)
values(0,#paperId,#ConferenceRoleId,#Deitails);select
SCOPE_IDENTITY() as RPID";
cmd = new SqlCommand(query2, sqlCon);
cmd.Parameters.AddWithValue("#paperId",
paperId);
cmd.Parameters.AddWithValue("#ConferenceRoleId",
ConferenceRoleId);
string ReviewPaperId;
try
{
cmd.Connection.Open();
ReviewPaperId = cmd.ExecuteScalar().ToString();
cmd.Connection.Close();
}
catch (Exception ee) { throw ee; }
finally { cmd.Dispose(); }
thanks

You have a SQL query with a parameter named Details, but you forgot to add the parameter.

You have a line of code which says
string query2 = #"insert into ReviewPaper(Overall_Rating, Paper_id,
Conference_role_id, Deitails) values (0,#paperId,#ConferenceRoleId,#Deitails);
select SCOPE_IDENTITY() as RPID";
You provide the parameters #paperId, #ConferenceRoleId and #Deitails for the values for the insert statement. Later you specify the value for the first two parameters, but not #Deitails:
cmd.Parameters.AddWithValue("#paperId", paperId);
cmd.Parameters.AddWithValue("#ConferenceRoleId", ConferenceRoleId);
You need to add a similar line to add the value for #Deitails so that SQL server knows what to do with it. The error you are getting is coming from SQL server because by not adding a value for #Deitails in your C# code, it is not being declared for you in the SQL code which is sent to the server.
To answer your other question, 'Scalar' in this case means that the variable #Deitails represents a single value.