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How to copy Access table to SQL table in C#?

As title says I've used odbcconnection to sqlconnection and for the life of me cant get it to work.. Copied a bunch of code from this site but cant get them both to work.
The program just hangs so maybe I am doing something wrong, but would appreciate maybe a bare bones template that i could just fill in the connection details and bulk copy the table to table..
using (OdbcConnection myConnection = new OdbcConnection())
{
string myConnectionString = #"Driver={Microsoft Access Driver (*.mdb)};" +
"Dbq=//####/data/Toronto/wrkgrp/wrkgrp30/Business Risk Oversight and Control/DATA INTEGRITY/CDE/CDE Testing Portal Requirements/Migration Requirements/RCM/Mutual Funds/Mutual Funds.mdb;";
myConnection.ConnectionString = myConnectionString;
myConnection.Open();
//execute queries, etc
OdbcCommand cmd = myConnection.CreateCommand();
cmd.CommandText = "SELECT * FROM RCM_MF_New_Accounts_Samples";
OdbcDataReader reader = cmd.ExecuteReader(); // close conn after complete
DataTable myDataTable = new DataTable();
myDataTable.Load(reader);
//myConnection.Close();
string destinationConnectionString = "Data Source=####;Initial Catalog=DYOF_STAGING_BROC;User ID=;Password=;Connection Timeout=999";
SqlConnection destination = new SqlConnection(destinationConnectionString);
SqlBulkCopy bulkData;
//destination.Open();
Exception ex = null;
try
{
Console.WriteLine("step1");
bulkData = new SqlBulkCopy(destinationConnectionString, SqlBulkCopyOptions.FireTriggers);
bulkData.BulkCopyTimeout = 1;
bulkData.DestinationTableName = "Load_CTR_Sample_Account_Opening2";
bulkData.WriteToServer(myDataTable);
bulkData.Close();
Console.WriteLine("moved from here to there");
reader.Close();
//destination.Close();
}
catch (Exception e)
{
ex = e;
}

I actually wrote an ORM to make this kind of task easier.
var accessDS = new AccessDataSource(connectionString1);
var dt = accessDS.From("RCM_MF_New_Accounts_Samples").ToDataTable().Execute();
var sqlDS = new SqlServerDataSource(connectionString2);
sqlDS.InsertBulk("Load_CTR_Sample_Account_Opening2", dt).Execute();
This does not work for .NET Core.
Packages:
https://www.nuget.org/packages/Tortuga.Chain.Access/
https://www.nuget.org/packages/Tortuga.Chain.SqlServer

Read the data from Access into a DataTable:
string strConnect = #"Provider=Microsoft.ACE.OLEDB.12.0;data source=D:\Temp\MyDB.accdb";
DataTable dt = new DataTable();
using (OleDbConnection con = new OleDbConnection(strConnect))
{
OleDbCommand cmd = new OleDbCommand("SELECT * FROM MyTable", con);
con.Open();
OleDbDataAdapter da = new OleDbDataAdapter(cmd);
da.Fill(dt);
}
Then use SqlBulkCopy to update SQL:
string strConnect = #"Data Source=GRIFFPC\SQLEXPRESS;Initial Catalog=Testing;Integrated Security=True";
using (SqlConnection con = new SqlConnection(strConnect))
{
con.Open();
using (SqlBulkCopy bulk = new SqlBulkCopy(con))
{
bulk.DestinationTableName = "Test";
bulk.WriteToServer(dt);
}
}
Of course, there is a much easier way to go straight from Access to SQL Server, using VBA, SQL , or other methods.
https://support.office.com/en-us/article/import-or-link-to-data-in-an-sql-server-database-a5a3b4eb-57b9-45a0-b732-77bc6089b84e
https://www.sqlshack.com/six-different-methods-to-copy-tables-between-databases-in-sql-server/

Here's a basic example of bulk insert.
public void BulkInsert(DataTable employees)
{
if (employees == null)
throw new ArgumentNullException(nameof(employees), $"{nameof(employees)} is null.");
using (var con = OpenConnection())
using (var sbc = new SqlBulkCopy(con))
{
sbc.DestinationTableName = "HR.Employee";
foreach (DataColumn column in employees.Columns)
sbc.ColumnMappings.Add(column!.ColumnName, column.ColumnName);
sbc.WriteToServer(employees);
}
}
Note the foreach (DataColumn column in employees.Columns) loop. This is required so that it knows the column names are the same in the source and the target table. (If they're not the same, manually map them in the same fashion.)
Source: https://grauenwolf.github.io/DotNet-ORM-Cookbook/BulkInsert.htm#ado.net

Following option need to verify
1) Column Name should be the same.
2) verify the column length.
3) verify the data type.

SqlHelper DataAdapter

I am using a SqlHelper class which has common methods for CRUD operations.
public static void Fill(DataSet dataSet, String procedureName)
{
SqlConnection oConnection = new SqlConnection(DBInterface.ConnectionString);
SqlCommand oCommand = new SqlCommand(procedureName, oConnection);
oCommand.CommandType = CommandType.StoredProcedure;
SqlDataAdapter oAdapter = new SqlDataAdapter();
oAdapter.SelectCommand = oCommand;
oConnection.Open();
using (SqlTransaction oTransaction = oConnection.BeginTransaction())
{
try
{
oAdapter.SelectCommand.Transaction = oTransaction;
oAdapter.Fill(dataSet);
oTransaction.Commit();
}
catch
{
oTransaction.Rollback();
throw;
}
finally
{
if (oConnection.State == ConnectionState.Open)
oConnection.Close();
oConnection.Dispose();
oAdapter.Dispose();
}
}
}
Now in my code, I am calling this method as,
private void BindCustomers()
{
DataSet dsCust = new DataSet();
SqlHelper.Fill(dsCust, "getCustomers");
--then I bind this dataset to datagridview
}
This all works fine. Now I want to update the data in the database. But I am confused how do I call DataAdatpaer.Update(dataset) here to update the changes made in datagridview into database. Is this possible here? Or I need to do it conventionally to find the updated row and call the ExecuteNonQuery function in the SqlHelper? Is there anything which can be done to use dataadapter.update(ds)
Thanks

You don't need to hide data adapter, or if for any reason you did so, you need to expose a method in your class to push updates to server.
Example
Public class SqlHelper
{
string commandText;
string connectionString;
public SqlHelper(string command, string connection)
{
commandText = command;
connectionString = connection;
}
public DataTable Select()
{
var table = new DataTable();
using (var adapter = new SqlDataAdapter(this.commandText, this.connectionString))
adapter.Fill(table)
return table;
}
public void Update(DataTable table)
{
using (var adapter = new SqlDataAdapter(this.commandText, this.connectionString))
{
var builder = new SqlCommandBuilder(adapter);
adapter.Update(table);
}
}
}

By calling this method in your code you can perform all crud operation select, update, delete and insert. you just need to pass connection string, procedure name and parameters list. Using this method you will retrieve data in the DataTable.if anyone want Dataset(Multiple Result) then just need to replace DataSet on the place of DataTable
SqlConnection conn = new SqlConnection("Your ConnectionString");
public DataTable ExecuteDataTable(string ProcedureName, SqlParameter[] _Param)
{
try
{
DataTable dataTable = new DataTable();
SqlCommand cmd = new SqlCommand(ProcedureName, conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Clear();
if (_Param is not null)
{
for (int i = 0; i < _Param.Length; i++)
{
if (_Param[i].ParameterName is not null)
{
if (_Param[i].Value is not null)
{
cmd.Parameters.AddWithValue(_Param[i].ParameterName, _Param[i].Value);
}
else
{
cmd.Parameters.AddWithValue(_Param[i].ParameterName, DBNull.Value);
}
}
}
}
conn.Open();
SqlDataAdapter DA = new SqlDataAdapter(cmd);
DA.Fill(dataTable);
conn.Close();
return dataTable;
}
catch (Exception ex)
{
conn.Close();
throw;
}
}

Listbox isn't populating with Data

I have set up a listbox called lboxsupplier, i have also created a data adapter which i then used to populate the supplier listbox. When i run the form the listbox is empty. I want the listbox to populate with supplier ID and company which i will then click on to populate another listbox with products.
Namespace Pennyburn_Greg
{
public partial class FormProcess : Form
{
SqlDataAdapter daSupplier;
DataSet dsPennyburnGreg = new DataSet();
SqlConnection conn;
SqlCommand cmdSupplierDetails;
SqlCommandBuilder cmdBSupplier;
DataRow drSupplier;
String connstr, sqlSupplier;
public FormProcess()
{
InitializeComponent();
}
private void FormProcess_Load(object sender, EventArgs e)
{
connstr = #"Data Source= arlene-pc; Initial Catalog= PennyburnGreg; Integrated Security=True";
//dataAdapter for supplier listbox
sqlSupplier = #"Select* from Supplier";
conn = new SqlConnection(connstr);
cmdSupplierDetails = new SqlCommand(sqlSupplier, conn);
daSupplier = new SqlDataAdapter(cmdSupplierDetails);
daSupplier.FillSchema(dsPennyburnGreg, SchemaType.Source, "Supplier");
}
private void filllboxsupplier(string str)
{
daSupplier.Fill(dsPennyburnGreg, "Supplier");
lboxsupplier.DataSource = dsPennyburnGreg.Tables["Supplier"];
lboxsupplier.DisplayMember = "Company";
lboxsupplier.ValueMember = "SupplierID";
}
}
}

First of all, why are you calling FillSchema, rather should be calling Fill method to get the data, like
daSupplier.Fill(dsPennyburnGreg, "Supplier");
Once you have the dataset filled, then in your FormProcess_Load() you can add the dataset as datasource to the listbox like
lboxsupplier.DataSource = dsPennyburnGreg.Tables["Supplier"]

First thing you need to do is loosely couple your UI and data a little bit. Try this code:
// Returns a DataTable of ALL suppliers
private DataTable GetSuppliers()
{
return GetSuppliers(0);
}
// Returns a DataTable of the given supplier
private DataTable GetSuppliers(int supplierId)
{
using (var connection = new SqlCommand())
{
connection.ConnectionString = #"Data Source= arlene-pc; Initial Catalog= PennyburnGreg; Integrated Security=True";
using (var command = new SqlCommand())
{
connection.Open();
command.CommandType = CommandType.Text;
command.Connection = connection;
if (supplierId == 0)
{
command.commandText = "SELECT * FROM Supplier";
}
else
{
command.commandText = "SELECT * FROM Supplier WHERE SupplierId=#id";
command.Parameters.AddWithValue("#id", supplierId);
}
using (var adapter = new SqlDataAdapter())
{
using (var ds = new DataSet())
{
adapter.SelectCommand = command;
adapter.Fill(ds);
if (ds.Tables.Count > 0)
return ds.Tables[0];
}
}
}
}
return null;
}
And now you can just do this:
lboxsupplier.DataSource = GetSuppliers(int.Parse(lboxsupplier.SelectedValue));
lboxsupplier.DisplayMember = "Company";
lboxsupplier.ValueMember = "SupplierID";
Or if you need all Suppliers, just do this:
lboxsupplier.DataSource = GetSuppliers();
lboxsupplier.DisplayMember = "Company";
lboxsupplier.ValueMember = "SupplierID";
This code will provide some separation. This is still not ideal, but beats what you had.

You're not doing anything with the listbox control in FormProcess_Load, so it will be empty when it first loads. I'm assuming you have lboxsupplier_Click bound to the Click event of lboxsupplier? If so, then you'll need to click on that listbox before it will populate the Dataset (which is a very odd user experience, but if that's truly what you need...). If lboxsupplier_Click isn't an event handler, then you're going to have to manually call it.
If it still isn't populating, then try running your query against the database directly, and make sure that it returns data and has columns named "Company" and "SupplierID"

C# Mysql multiple queries

Im trying to build up a little status-tool. I need to get results of multiple queries (about 4-5). The general connection-setup and 'how-to-read-data' is already done but I cant figure out how the another query executed.
Everything I found while searching for it is for the SqlClient. Im totally overcharged with this.
Here is my code so far (be patient, im a newbie to this):
private void button1_Click(object sender, EventArgs e)
{
if(listView1.Items.Count > 1)
{
listView1.Items.Clear();
}
var listMember = new List<string>{};
var listOnline = new List<string>{};
// SQL PART //
string connString = "Server=10*****;Port=3306;Database=e***;Uid=e***;password=********************;";
MySqlConnection conn = new MySqlConnection(connString);
MySqlCommand command = conn.CreateCommand();
command.CommandText = "SELECT fullname,online FROM member WHERE active = '1' ORDER BY online DESC";
try
{
conn.Open();
}
catch (Exception ex)
{
listView1.Items.Add("Error: " + ex);
}
MySqlDataReader reader = command.ExecuteReader();
while(reader.Read())
{
listMember.Add(reader["fullname"].ToString());
listOnline.Add(reader["online"].ToString());
}
conn.Close();
// SQL ENDING //
// SET ENTRIES TO LISTVIEW //
int counter = 0;
foreach(string member in listMember)
{
ListViewItem item = new ListViewItem(new[] { member, listOnline.ElementAt(counter) });
item.ForeColor = Color.Green;
listView1.Items.Add(item);
counter++;
}
}
Im not really sure how the design/layout will look like in the end, so I would like to just append the results to lists in the sql-part to process the data later out of the lists.
Do I really have to setup a complete new connection after conn.Close()? Or is there any other way? I can just imagine: 5 queries with their own connection,try,catch and 2 loops... this will get about 100-200 lines just for getting the results out of 5 queries. Isnt that a bit too much for such an easy thing?
Hope for some help.
Greetings.
According to the new comments my latest code:
Top:
public partial class Form1 : Form
{
public static string connString = "Server=10****;Port=3306;Database=e****;Uid=e****;password=****;";
public Form1()
{
InitializeComponent();
MySqlConnection conn = new MySqlConnection(connString); // Error gone!
}
Body part:
public void QueryTwoFields(string s, List<string> S1, List<string> S2)
{
try
{
MySqlCommand cmd = conn.CreateCommand(); // ERROR: conn does not exist in the current context.
cmd.CommandType = CommandType.Text;
string command = s;
cmd.CommandText = command;
MySqlDataReader sqlreader = cmd.ExecuteReader();
while (sqlreader.Read())
{
S1.Add(sqlreader[0].ToString());
S2.Add(sqlreader[1].ToString());
}
sqlreader.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
private void button1_Click(object sender, EventArgs e)
{
if(listView1.Items.Count > 1)
{
listView1.Items.Clear();
}
var listMember = new List<string>{};
var listOnline = new List<string>{};
using (conn) // ERROR: conn does not exist in the current context.
{
conn.Open();
///...1st Query
QueryTwoFields("SELECT fullname,online FROM member WHERE active = '1' ORDER BY online DESC",listMember,listOnline);
//...2nd query
//QueryTwoFields("your new Select Statement", otherList, otherList);
}
}

You don't have to close connection every time you execute one query rarher than close the sqlreader assigned to that connection. Finally when all of your queries have been executed you close the connection. Consider also the use of using:
You cal also define a method for execution your Query in order for your code not to be repetive:
public void QueryTwoFields(string s, List<string> S1, List<string> S2)
///Select into List S1 and List S2 from Database (2 fields)
{
try
{
MySqlCommand cmd = conn.CreateCommand();
cmd.CommandType = CommandType.Text;
string command = s;
cmd.CommandText = command;
MySqlDataReader sqlreader = cmd.ExecuteReader();
while (sqlreader.Read())
{
S1.Add(sqlreader[0].ToString());
S2.Add(sqlreader[1].ToString());
}
sqlreader.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
private void button1_Click(object sender, EventArgs e)
{
if(listView1.Items.Count > 1)
{
listView1.Items.Clear();
}
var listMember = new List<string>{};
var listOnline = new List<string>{};
// SQL PART //
using (conn)
{
conn.Open();
///...1st Query
QueryTwoFields("SELECT fullname,online FROM member WHERE active = '1' ORDER BY online DESC",listmember,listonline)
//...2nd query
QueryTwoFields("your new Select Statement",myOtherList1,myOtherlist2)
....
}
}
EDIT :
Take in mind you cant define QueryTwoFields method inside button handler. You must define it outside (see code above).
Also Define your connection data in the start of the programm:
namespace MyProject
{
/// <summary>
/// Defiine your connectionstring and connection
/// </summary>
///
public partial class Form1 : Form
{ public static string connString = "Server=10*****;Port=3306;Database=e***;Uid=e***;password=********************;";
MySqlConnection conn = new MySqlConnection(connString);
.........

Datatables are fantastic
Using a data table is a nice way to do both read and write. And it comes with the luxury of eveything you can do with a datatable - like asssigning it directly to a datagrid control, sorting, selecting and deleting while disconnected.
The sample below assumes a MySqlConnection conection property managed by calls to your own OpenConnection() and CloseConnection() methods not shown.
Simple datatable read demo:
public DataTable Select(string query = "")
{
//Typical sql: "SELECT * FROM motorparameter"
DataTable dt = new DataTable();
//Open connection
if (this.OpenConnection() == true)
{
//Create Command
MySqlCommand cmd = new MySqlCommand(query, connection);
//Create a data reader and Execute the command
MySqlDataReader dataReader = cmd.ExecuteReader();
dt.Load(dataReader);
//close Data Reader
dataReader.Close();
//close Connection
this.CloseConnection();
//return data table
return dt;
}
else
{
return dt;
}
}
In case of writing back the datatable to the database - supply the SQL you used in the read (or would have used to read to the data table):
public void Save(DataTable dt, string DataTableSqlSelect)
{
//Typically "SELECT * FROM motorparameter"
string query = DataTableSqlSelect;
//Open connection
if (this.OpenConnection() == true)
{
//Create Command
MySqlCommand mySqlCmd = new MySqlCommand(query, connection);
MySqlDataAdapter adapter = new MySqlDataAdapter(mySqlCmd);
MySqlCommandBuilder myCB = new MySqlCommandBuilder(adapter);
adapter.UpdateCommand = myCB.GetUpdateCommand();
adapter.Update(dt);
//close Connection
this.CloseConnection();
}
else
{
}
}
The neat thing the datatable is extremely flexible. You can run your own selects against the table once it contains data and before writing back you can set or reset what rows needs updating and by default the datatable keeps track of what rows you update in the table. Do not forget primary key column(s) for all tables in the db.
For multiple queries consider if possible using a join between the database tables or same table if data related or use a UNION sql syntax if column count and type of data is the same. You can allways "create" your extra column in the select to differ what data comes from what part of the UNION.
Also consider using CASE WHEN sql syntax to conditionally select data from different sources.

C# Database connection

I have a homework about database connection via ms access.
I prepared my database and saved it as dbMert and put it to debug / bin
This is my CustomerDatabase class for connecting to database:
static class CustomerDatabase
{
static string connectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=dbMert.mdb";
static OleDbConnection connection = null;
static OleDbCommand command = null;
public static void ConnectToDatabase()
{
if (connection == null)
{
connection = new OleDbConnection(connectionstring);
command = new OleDbCommand();
command.Connection = connection;
command.CommandText = "select * from Customer";
}
}
public static DataTable executeSelect(string sql)
{
ConnectToDatabase();
DataTable dt = null;
dt = new DataTable();
command.CommandText = sql;
OpenConnection();
OleDbDataReader datareader = command.ExecuteReader();
dt.Load(datareader);
datareader.Close();
CloseConnection();
return dt;
}
public static void OpenConnection()
{
try
{
if (connection != null)
{
connection.Open();
}
}
catch (Exception ex)
{
}
}
public static void CloseConnection()
{
if (connection != null)
{
connection.Close();
}
}
}
}
Form: In constructor i try to connect to database
public Form1()
{
InitializeComponent();
CustomerDatabase.ConnectToDatabase();
}
and in form's load i try to take tuples to datagridview but nothing happens :S
private void Form1_Load(object sender, EventArgs e)
{
string sql1 = "select * from Customer";
DataTable dt = CustomerDatabase.executeSelect(sql1);
}

Regardless of other things (such as not keeping a single connection open, using using statements etc) you're not connecting your newly-loaded DataTable to your DataGridView at all. Your Form1_Load method just loads the data into a DataTable, then effectively throws it away.
I suspect you want something like:
dataGridView.DataSource = dt;
at the end of the method.
EDIT: Note that this is also a really bad idea in your OpenConnection code:
catch (Exception ex)
{
}
That basically says, "If something goes wrong, don't bother recording that fact or changing how the rest of the code works - just keep going as if nothing had happened."
Why are you catching the exception at all?

Try to write simple code. I suggest you to use OleDbDataAdaper, its Fill() method populate the DataTable easily.
You may use |DataDirectory| if you are using database (.mdb) located under Bin\Debug folder.
static string connectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;
Data Source=|DataDirectory|\dbMert.mdb";
Or
static string connectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;
Data Source=x:\full_path\dbMert.mdb";
Or
static string connectionstring = #"Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=x:\full_path\dbMert.mdb";
static class Test
{
static string connectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=dbMert.mdb";
public static DataTable executeSelect(string sql)
{
DataTable dt = new DataTable();
OleDbDataAdapter adapter = new OleDbDataAdapter(sql,connectionString);
adapter.Fill(dt);
return dt;
}
}
Add following code in form_load handler,
string sql1 = "select * from Customer";
DataTable dt = Test.executeSelect(sql1);
DataGridView1.DataSource=dt;

When I move the DB-file to bin/debug, an error message states "4.0 is not installed".
However, when I move it to bin, the problem is solved.
My code:
con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source= ..\\dbMert.mdb";
con.Open();
recordları
DataSet ds = new DataSet();
DataTable dt = new DataTable();
ds.Tables.Add(dt);
OleDbDataAdapter da = new OleDbDataAdapter();
da = new OleDbDataAdapter("Select * from Customer", con);
da.Fill(dt);
dataGridView1.DataSource = dt;
foreach (DataRow row in dt.Rows)
{
foreach (DataColumn col in dt.Columns)
if(col.ToString() == "emailAdress")
comboBox1.Items.Add(row[col]);
}
con.Close();