today, I am trying to use DataRoutines to insert some values into my Access Database. However, it did not work as well as there were no records created. Does anyone know what's wrong with my code?
This is my DataRoutines (dataroutines2) file
public void CreateRecs(string strUserId)
{
OleDbConnection mDB = new OleDbConnection();
mDB.ConnectionString = "Provider = Microsoft.ACE.OLEDB.12.0;Data source="
+ Server.MapPath("~/App_Data/webBase.accdb");
OleDbCommand cmd; OleDbDataReader rdr;
string strSql;
string strOFlag = "F";
// check to see if there is an active order record
strSql = "SELECT eStatus FROM enrolInfo WHERE eUserId = #UserId "
+ "ORDER BY eEnrolNo DESC;";
cmd = new OleDbCommand(strSql, mDB);
cmd.Parameters.Add("#UserId", OleDbType.Char).Value = strUserId;
mDB.Open();
rdr = cmd.ExecuteReader();
Boolean booRows = rdr.HasRows;
if (booRows) //when booRows is true, there are order records for the user
{
rdr.Read();
if ((string)rdr["eStatus"] != "Ordering") //status of an active order is "Ordering"
{
strOFlag = "M"; //"T" means there is a need to create a new Orders record
}
else { strOFlag = "M"; }
mDB.Close();
if (strOFlag == "M")
{
//insert a new order record
string strStatus = "Ordering";
strSql = "INSERT INTO enrolInfo (eUserId, eStatus) VALUES (#UserId, #Status)";
cmd = new OleDbCommand(strSql, mDB);
cmd.Parameters.AddWithValue("#UserId", strUserId);
cmd.Parameters.AddWithValue("#Status", strStatus);
mDB.Open();
cmd.ExecuteNonQuery();
mDB.Close();
}
//get back order No - this order no is needed when the user buys an item
strSql = "SELECT eEnrolNo FROM enrolInfo WHERE eUserId = #UserId "
+ "ORDER BY eEnrolNo DESC;";
cmd = new OleDbCommand(strSql, mDB);
cmd.Parameters.Add("#UserId", OleDbType.Char).Value = strUserId;
mDB.Open();
rdr = cmd.ExecuteReader();
rdr.Read();
Session["tOrderNo"] = rdr["eEnrolNo"]; //store the active order no in the sOrderNo
mDB.Close();
return;
}
}
This is the code that will route the solution to the DataRoutines file in my Register Page
//prepare Session variables for newly register customer
Session["sFlag"] = "M";
Session["tUserId"] = (string)txtUserId.Text;
Session["tName"] = (string)txtName.Text;
Session["tAddress"] = (string)txtAddress.Text;
Session["tTel"] = (string)txtTel.Text;
Session["tEmail"] = (string)txtEmail.Text;
String strUserId = (string)Session["tUserId"];
DataRoutines2 DRObject = new DataRoutines2();
DRObject.CreateRecs(strUserId);
Thanks for your help
Related
I am developing an application in C# where I'm trying to use Oracle Database Change Notification.
When I'm using DCN for one table, everything is working as expected but when I am trying to use two tables, I get the following error: "Attempted to read or write protected memory. This is often an indication that other memory is corrupt", on the line cmd.ExecuteNonQuery();
Here is the code:
string sql = "select rowid, first_name, last_name, salary from employees where employee_id = :1" +
"select country_id, country_name, region_id from countries where country_id = :2";
string constr = "User Id=hr;Password=Parola_007;Data Source=ORCL;Pooling=false";
con = new OracleConnection(constr);
con.Open();
OracleCommand cmd = new OracleCommand(sql, con);
OracleParameter p_id = new OracleParameter();
p_id.OracleDbType = OracleDbType.Decimal;
p_id.Value = 149;
OracleParameter p_id2 = new OracleParameter();
p_id2.OracleDbType = OracleDbType.Varchar2;
p_id2.Value = "BE";
cmd.BindByName = true;
cmd.Parameters.Add(p_id);
cmd.Parameters.Add(p_id2);
OracleDependency dep = new OracleDependency(cmd);
cmd.Notification.IsNotifiedOnce = false;
dep.OnChange += new OnChangeEventHandler(OnDatabaseNotification);
cmd.ExecuteNonQuery();
public static void OnDatabaseNotification(object src, OracleNotificationEventArgs args)
{
string sql = "select rowid, first_name, last_name, salary from employees where rowid = :1" +
"select rowid, country_id, country_name, region from countries where rowid = :2";
OracleParameter p_rowid = new OracleParameter();
p_rowid.Value = args.Details.Rows[0]["rowid"];
OracleParameter p_rowid2 = new OracleParameter();
p_rowid2.Value = args.Details.Rows[1]["rowid"];
OracleCommand cmd = con.CreateCommand();
cmd.CommandText = sql;
cmd.BindByName = true;
cmd.Parameters.Add(p_rowid);
cmd.Parameters.Add(p_rowid2);
OracleDataReader dr = cmd.ExecuteReader();
dr.Read();
Console.WriteLine();
Console.WriteLine("Database Change Notification received!");
DataTable changeDetails = args.Details;
Console.WriteLine("Resource {0} has changed.", changeDetails.Rows[0]["ResourceName"]);
Console.WriteLine("Resource {1} has changed.", changeDetails.Rows[1]["ResourceName"]);
dr.Dispose();
cmd.Dispose();
p_rowid.Dispose();
}
Am I doing something wrong?
Thanks.
1: you cannot do 2 sql in 1 command.
2: You can use the table trigger in oracle to check the changed table data. All changes should be logged in a table and only need to be query from that table.
sorry for my english
I am stuck on collecting 2 column values from a database row.
this method is only working to retrieve one value, not for 2. I need to save values from cells to Different variables then I will use these variables to populate another database.
string connectionString = #"Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=Northwind;Integrated Security=True";
using (var con2 = new SqlConnection(connectionString))
{
try
{
con2.Open();
SqlCommand command = new SqlCommand();
command.Connection = con2;
command.CommandText = string.Format("update Inventory set Quantity= Quantity - {0} WHERE id='"+tbItemid.Text+"'", Convert.ToInt32(tbQuantity.Text));
command.ExecuteNonQuery();
con2.Close();
Data();
DData();
con2.Open();
int x = int.Parse(tbQuantity.Text);
SqlCommand cmd1 = new SqlCommand("SELECT Model from Inventory WHERE id='" + tbItemid.Text + "'", con2);
SqlDataReader modelRdr = null;
modelRdr = cmd1.ExecuteReader();
modelRdr.Read();
modelRdr = cmd1.ExecuteReader();
string model = modelRdr["model"].ToString();
con2.Close();
con.Open();
int y = int.Parse(tbQuantity.Text);
SqlCommand cmd2 = new SqlCommand("SELECT Price from Inventory WHERE id='" + tbItemid.Text + "'", con2);
SqlDataReader pricerdr = null;
pricerdr = cmd2.ExecuteReader();
pricerdr.Read();
int price = int.Parse(pricerdr["Price"].ToString());
SqlCommand cmd = con.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "insert into Bill values (" + tbItemid.Text + ",'" +model.ToString()+ "',"+price.ToString()+",'"+tbQuantity.Text+"')";
cmd.ExecuteNonQuery();
con.Close();
Data();
}
catch
{
MessageBox.Show("Enter Catagory and Product ID");
}
}
First thing first you should use Parameterized Queries instead of Concatenations. These kind of queries are prone to SQL Injection. You can read both the columns in one command
SqlCommand cmd1 = new SqlCommand("SELECT Model, Price from Inventory WHERE id='" + tbItemid.Text + "'", con2);
SqlDataReader modelRdr = null;
modelRdr = cmd1.ExecuteReader();
modelRdr.Read();
modelRdr = cmd1.ExecuteReader();
string model = modelRdr["model"].ToString();
int price = int.Parse(modelRdr["Price"].ToString());
The complete code with Parameters would look like
string model=String.Empty;
int price = 0;
string connectionString = #"Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=Northwind;Integrated Security=True";
using (SqlConnection con2 = new SqlConnection(connectionString))
{
try
{
con2.Open();
using(SqlCommand command = new SqlCommand())
{
command.Connection = con2;
command.CommandText = string.Format("update Inventory set Quantity = Quantity - #qty WHERE id=#id";
command.Parameters.AddWithValue("#id", tbItemid.Text);
command.Parameters.AddWithValue("#qty", Convert.ToInt32(tbQuantity.Text)));
command.ExecuteNonQuery();
Data();
DData();
int x = int.Parse(tbQuantity.Text);
using(SqlCommand cmd1 = new SqlCommand("SELECT Model, Price from Inventory WHERE id=#id"))
{
cmd1.Parameters.AddWithValue("#id", tbItemid.Text);
SqlDataReader modelRdr = null;
modelRdr = cmd1.ExecuteReader();
modelRdr.Read();
model = modelRdr["model"].ToString();
price = int.Parse(modelRdr["Price"].ToString());
}
using(SqlCommand cmd = con.CreateCommand())
{
cmd.CommandType = CommandType.Text;
cmd.CommandText = "insert into Bill values (#id,#model,#price,#qty)";.
cmd.Parameters.AddWithValue("#id", tbItemid.Text);
cmd.Parameters.AddWithValue("#model", model);
cmd.Parameters.AddWithValue("#price", price);
cmd.Parameters.AddWithValue("#qty", tbQuantity.Text);
cmd.ExecuteNonQuery();
}
Data();
}
catch
{
MessageBox.Show("Enter Catagory and Product ID");
}
}
}
i have a project, and part of it asks the user to input the ID of the patient to show his/her details
This is my code
sConnection = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=hospital database.accdb";
dbConn = new OleDbConnection(sConnection);
dbConn.Open();
sql = "SELECT * FROM Patients";
dbCmd = new OleDbCommand();
dbCmd.CommandText = sql;
dbCmd.Connection = dbConn;
dbReader = dbCmd.ExecuteReader();
listBox1.Items.Clear();
if (dbReader.HasRows)
{
while (dbReader.Read())
{
if (dbReader["PatientID"] != DBNull.Value)
{
int anInteger;
anInteger = Convert.ToInt32(textBox7.Text);
anInteger = int.Parse(textBox7.Text);
if (anInteger == 101)
{
}
}
}
}
in the IF statement, i dont know what to write in it, to display on the row of the patient with this ID only
Please Help!!
Instead of selecting all rows, it is much more efficient to filter the one row you are looking for using a parameter and modifying your SQL statement as follows.
sql = "SELECT * FROM Patients WHERE PatientID = [pID]";
dbCmd = new OleDbCommand();
dbCmd.CommandText = sql;
dbCmd.Connection = dbConn;
dbcmd.Parameters.AddWithValue("pID", 101);
dbReader = dbCmd.ExecuteReader();
I would also suggest looking into the "using" clause. Here's a SO example.
sql = "SELECT Count(*) FROM Patients WHERE PatientID = #PID";
dbCmd = new OleDbCommand();
dbCmd.CommandText = sql;
dbCmd.Connection = dbConn;
dbcmd.Parameters.AddWithValue("#PID", 101);
Int32 Cnt = dbCmd.ExecuteScalar();
if ( Cnt > 0)
{
// Do Something
}
else { // Do something}
you have to use a variable to be sure that your ID was found and and break; to exit your loop once it was found
if (dbReader.HasRows)
{
bool found = false;
while (dbReader.Read())
{
if (dbReader["PatientID"] != DBNull.Value)
{
int anInteger;
anInteger = Convert.ToInt32(textBox7.Text);
anInteger = int.Parse(textBox7.Text);
if (anInteger == 101)
{
found = true ; Break;
}
}
}
}
int anInteger = Convert.ToInt32(textBox7.Text);
sConnection = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=hospital database.accdb";
dbConn = new OleDbConnection(sConnection);
dbConn.Open();
sql = "SELECT * FROM Patients where PatientID=#PatientID";
dbCmd = new OleDbCommand();
dbCmd.CommandText = sql;
dbCmd.Parameters.AddWithValue("#PatientID",anInteger);
dbCmd.Connection = dbConn;
dbReader = dbCmd.ExecuteReader();
listBox1.Items.Clear();
while (dbReader.Read())
{
//now display the reader values here : sample
//TextBox1.Text=dbReader["name"].ToString();
}
I am making a booking system.
I can't figure out the validation algorithm for a series of data before it insert to DB.
The primary key will be the booking ID which is automatic generate by the system.
I need to validate the bdate, btime and sname. (bdate=booking time, btime=booking time, and sname=staff name)
In case of the bdate, btime and sname is same as what the client input. the system will alert its duplicate as the staff already have booking on the same date and time.
Please find my insert query at below and appreciated you can point me to the right way.
private void btn_save_Click(object sender, EventArgs e)
{
OleDbCommand cmd = new OleDbCommand();
cmd.CommandType = CommandType.Text;
//query for duplicate
cmd.CommandText = "select count(*) from Booking where sname = #newName and bdate = #newDate and btime = #newTime";
// cmd.Parameters.Add("#newName", OleDbType.VarChar).Value = txt_cname.Text;
//cmd.Parameters.Add("#newDate", OleDbType.DBDate).Value = dtp_bdate.Value.Date;
// cmd.Parameters.Add("#newTime", OleDbType.VarChar).Value = dtp_btime.Value.ToString("hh:mm tt");
cmd.CommandText = "insert into Booking(cname, bdate, btime, ccontact, sname) Values('" + txt_cname.Text + "','" + dtp_bdate.Value.Date + "','" + dtp_btime.Value.ToString("hh:mm tt") + "','" + txt_ccontact.Text + "','" + txt_sname.Text + "')";
cmd.Connection = myCon;
myCon.Open();
int recordCount = Convert.ToInt32(cmd.ExecuteScalar());
myCon.Close();
if (recordCount>0)
{
// handle duplicates
MessageBox.Show("Duplicated", "My Application",
MessageBoxButtons.OKCancel, MessageBoxIcon.Asterisk);
}
// cmd.Connection = myCon;
//myCon.Open();
//cmd.ExecuteNonQuery();
//myCon.Close();
//MessageBox.Show(dtp_bdate.Value.ToString());
//MessageBox.Show("Booking completed", "My Application",
// MessageBoxButtons.OKCancel, MessageBoxIcon.Asterisk);
}
private bool RecordExists(string name, DateTime date, string time)
{
OleDbCommand cmd = new OleDbCommand();
cmd.CommandType = CommandType.Text;
//query for duplicate
cmd.CommandText = "select count(*) from Booking where sname = #newName and bdate = #newDate and btime = #newTime";
cmd.Parameters.Add("#newName", OleDbType.VarChar).Value = txt_cname.Text;
cmd.Parameters.Add("#newDate", OleDbType.DBDate).Value = dtp_bdate.Value.Date;
cmd.Parameters.Add("#newTime", OleDbType.VarChar).Value = dtp_btime.Value.ToString("hh:mm tt");
myCon.Open();
int recordCount = Convert.ToInt32(cmd.ExecuteScalar());
myCon.Close();
return recordCount > 0;
}
private void btn_save_Click(object sender, EventArgs e)
{
if (RecordExists(txt_cname.Text, dtp_bdate.Value.Date, dtp_btime.Value.ToString("hh:mm tt"))
{
MessageBox.Show("Duplicated", "My Application", MessageBoxButtons.OKCancel, MessageBoxIcon.Asterisk);
return;
}
OleDbCommand cmd = new OleDbCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "insert into Booking(cname, bdate, btime, ccontact, sname) Values(#newName, #newDate, #newTime, #newContact, #newSName)";
cmd.Parameters.Add("#newName", OleDbType.VarChar).Value = txt_cname.Text;
cmd.Parameters.Add("#newDate", OleDbType.DBDate).Value = dtp_bdate.Value.Date;
cmd.Parameters.Add("#newTime", OleDbType.VarChar).Value = dtp_btime.Value.ToString("hh:mm tt");
cmd.Parameters.Add("#newContact", OleDbType.VarChar).Value = txt_ccontact.Text;
cmd.Parameters.Add("#newSName", OleDbType.VarChar).Value = txt_sname.Text;
cmd.Connection = myCon;
myCon.Open();
cmd.ExecuteNonQuery();
myCon.Close();
MessageBox.Show(dtp_bdate.Value.ToString());
MessageBox.Show("Booking completed", "My Application", MessageBoxButtons.OKCancel, MessageBoxIcon.Asterisk);
}
you'll need to check if the booking exists before performing your insert, so you need to add an additional step:
OleDbCommand cmd = new OleDbCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "select count(*) from booking where cname = #newName and bdate = #newDate and ctime = #newTime";
cmd.Parameters.Add("#newName", OleDbType.VarChar).Value = txt_cname.Text;
cmd.Parameters.Add("#newDate", OleDbType.DBDate).Value = dtp_bdate.Value.Date;
cmd.Parameters.Add("#newTime", OleDbType.VarChar).Value = dtp_btime.Value.ToString("hh:mm tt");
cmd.Connection = myCon;
myCon.Open();
int recordCount = Convert.ToInt32(cmd.ExecuteScalar());
myCon.Close();
if (recordCount>0)
{
// handle duplicates
}
when you execute this, it will either return the number of matching rows, if this is 1 or more, then you should then invoke your duplicate logic.
edited to correct code
To check if there's existing field you can make a Select and then compare:
bool InfoRepeated()
{
OleDbCommand cmd = new OleDbCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = string.Format("SELECT cname FROM yourTable;");
cmd.Connection = myCon;
myCon.Open();
try
{
OleDbDataReader rdr = cmd.ExecuteReader();
while (rdr.Read())
{
if (txt_cname.Text.Equals((rdr[0].ToString())))
{
myCon.Close();
return true;
}
}
myCon.Close();
return false;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
myCon.Close();
return false;
}
}
Let me know if it works or the error you get.
working useful code try this
BOMaster obj_data = new BOMaster();
obj_data.productid = tempid;
obj_data.categoryid =int.Parse(cmbcategory.SelectedValue.ToString());
obj_data.productcode = txtproductcode.Text;
obj_data.productname = txtproductname.Text;
obj_data.mqty = decimal.Parse(txtmqty.Text.ToString());
OleDbCommand mycmd = new OleDbCommand("select * from productmaster where productname=?", new OleDbConnection(Common.cnn));
BOMaster obj_datan = new BOMaster();
mycmd.Parameters.Add(new OleDbParameter("productname", txtproductname.Text));
mycmd.Connection.Open();
OleDbDataReader myreader = mycmd.ExecuteReader(CommandBehavior.CloseConnection);
if (myreader.HasRows == true)
{
// savestutus = "false";
MessageBox.Show("Product Name Already Exist", "Product", MessageBoxButtons.OK, MessageBoxIcon.Information);
txtproductname.Focus();
return;
}
mycmd.Connection.Close();
ProductDAL obj_dal = new ProductDAL();
if (obj_dal.Save(obj_data))
{
Clear();
}
I'm trying to make a simple test program that can open MDB files and do 3 basic things
the MDB have 3 fields, all of them are text:
ID
INFO
TEXT
showing data acording to ID = got this working
changing data according to ID = problem
adding new data = problem
the show data works with this code:
con = new OleDbConnection("Provider = Microsoft.Jet.OLEDB.4.0; Data Source = c:\\mdb\\testmdb.mdb");
cmd = new OleDbCommand();
cmd.Connection = con;
cmd.CommandText = "select Info, text from Table1 where ID = '" + int.Parse(textBox1.Text) + "' ";
con.Open(); // open the connection
OleDbDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
textBox2.Text = dr["Info"].ToString();
textBox3.Text = dr["text"].ToString();
}
con.Close();
How do I insert new data in MDB and update data I already have?
Working code
using System;
using ADOX;
using System.Data.OleDb;
using System.Data;
using System.IO;
namespace ConsoleApplication4
{
class Program
{
static void Main(string[] args)
{
CreateMdb("toster_ru.mdb");
string fileNameWithPath = Environment.CurrentDirectory + "\\toster_ru.mdb";
CreateTableInToMdb(fileNameWithPath);
InsertToMdb(fileNameWithPath);
UpdateToMdb(fileNameWithPath);
var myDataTable = new DataTable();
using (var conection = new OleDbConnection("Provider = Microsoft.JET.OLEDB.4.0; Data Source = " + fileNameWithPath))
{
conection.Open();
var query = "Select info From my_table";
var adapter = new OleDbDataAdapter(query, conection);
adapter.Fill(myDataTable);
Console.WriteLine(myDataTable.Rows[0][0].ToString()); //output: toster2.ru
Console.ReadKey();
}
}
static void CreateMdb(string fileNameWithPath)
{
if (File.Exists(fileNameWithPath))
return;
Catalog cat = new Catalog();
string connstr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};Jet OLEDB:Engine Type=5";
cat.Create(String.Format(connstr, fileNameWithPath));
cat = null;
}
static void InsertToMdb(string fileNameWithPath)
{
var con = new OleDbConnection("Provider = Microsoft.Jet.OLEDB.4.0; Data Source = " + fileNameWithPath);
var cmd = new OleDbCommand();
cmd.Connection = con;
cmd.CommandText = "insert into my_table (ID, [Info], [text]) values (#ID, #Info, #text);";
cmd.Parameters.AddWithValue("#ID", 1);
cmd.Parameters.AddWithValue("#Info", "toster.ru");
cmd.Parameters.AddWithValue("#text", "blabla");
con.Open();
cmd.ExecuteNonQuery();
con.Close();
}
static void UpdateToMdb(string fileNameWithPath)
{
var con = new OleDbConnection("Provider = Microsoft.Jet.OLEDB.4.0; Data Source = " + fileNameWithPath);
var cmd = new OleDbCommand();
cmd.Connection = con;
cmd.CommandText = "UPDATE my_table SET [Info] = ?, [text] = ? WHERE ID = ?;";
cmd.Parameters.AddWithValue("#p1", OleDbType.VarChar).Value = "toster2.ru";
cmd.Parameters.AddWithValue("#p2", OleDbType.VarChar).Value = "blabla2";
cmd.Parameters.AddWithValue("#p3", OleDbType.VarNumeric).Value = 1;
con.Open();
cmd.ExecuteNonQuery();
con.Close();
}
static void CreateTableInToMdb(string fileNameWithPath)
{
try
{
OleDbConnection myConnection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" + fileNameWithPath);
myConnection.Open();
OleDbCommand myCommand = new OleDbCommand();
myCommand.Connection = myConnection;
myCommand.CommandText = "CREATE TABLE my_table([ID] NUMBER, [Info] TEXT, [text] TEXT)";
myCommand.ExecuteNonQuery();
myCommand.Connection.Close();
}
catch { }
}
}
}
Try this for insert:
con = new OleDbConnection("Provider = Microsoft.Jet.OLEDB.4.0; Data Source = c:\\mdb\\testmdb.mdb");
cmd = new OleDbCommand();
cmd.Connection = con;
cmd.CommandText = "insert (ID, Info, text) into Table1 values (#ID, #Info, #text);";
cmd.Parameters.AddWithValue("#ID", textBox1.Text);
cmd.Parameters.AddWithValue("#Info", textBox2.Text);
cmd.Parameters.AddWithValue("#text", textBox3.Text);
con.Open(); // open the connection
//OleDbDataReader dr = cmd.ExecuteNonQuery();
cmd.ExecuteNonQuery();
con.Close();
Try this for update:
con = new OleDbConnection("Provider = Microsoft.Jet.OLEDB.4.0; Data Source = c:\\mdb\\testmdb.mdb");
cmd = new OleDbCommand();
cmd.Connection = con;
cmd.CommandText = "update Table1 set [Info] = #Info, [text] = #text where ID = #ID;";
cmd.Parameters.AddWithValue("#ID", textBox1.Text);
cmd.Parameters.AddWithValue("#Info", textBox2.Text);
cmd.Parameters.AddWithValue("#text", textBox3.Text);
con.Open(); // open the connection
//OleDbDataReader dr = cmd.ExecuteNonQuery();
cmd.ExecuteNonQuery();
con.Close();
For more operations, examine the left panel of this site.