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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.

How do I return a table from a SQL query as a List in C#?

I have a Xamarin app that connects to a SQL Server (*), and I want to insert the data from the SQL Server's tables into a local SQLite database. My approach is to execute a query like
select * from Table1
retrieve the results of the query as a List, then insert that List into my SQLite table. That said I'm very new at using SqlClient, so please share if there are better ways to do this. Thanks.
Edit: the smallest number of columns these tables have is 5. Don't know if that disqualifies Lists as the best option.
My code:
private void LoadData()
{
string cs = #"connection string here";
using (SqlConnection sconn = new SqlConnection(cs))
{
sconn.Open();
SqlDataReader reader = null;
SqlCommand aml = new SqlCommand("select * from Table1");
reader = aml.ExecuteReader();
while (reader.Read())
{
// get result of query as List somehow?
}
using (SQLiteConnection conn = new SQLiteConnection(App.DatabaseLocation))
{
conn.CreateTable<Table1>();
if (conn.Query<Table1>("select * from Table1").Count() <= 0)
{
// insert the list object
}
}
}
}
(*) The app does not use a web service as the app is intended for onsite use only and will not be distributed publicly.

A better alternative way to do it more easier is to use a ORM like dapper
With the help of dapper, all you need to do is
using (var connection = new SqlConnection(_sqlConnectionString))
{
var results = connection.Query<YourTableModel>(query).ToList();
return results;
}

You can get data from the SQL Server as DataTable or convert it to a list as you prefer.
public DataTable GetDataTable(string connectionString, string tableName)
{
SqlConnection conn = new SqlConnection(connectionString);
conn.Open();
string query = $'SELECT * FROM [{tableName}]';
SqlCommand cmd = new SqlCommand(query, conn);
DataTable t1 = new DataTable();
using (SqlDataAdapter a = new SqlDataAdapter(cmd))
{
a.Fill(t1);
}
return t1;
}
Then use this table or list returned from the above method to insert in the SQLite table.
string cs = #"Data Source=datasource;Initial Catalog=databasename;User ID=user;Password=password";
DataTable table = GetDataTable(cs, "Table1");
using (SQLiteConnection conn = new SQLiteConnection(App.DatabaseLocation))
{
conn.CreateTable<Table1>();
if (conn.Query<Table1>("select * from Table1").Count() <= 0)
{
foreach(DataRow row in table.Rows)
{
//Access values of each row column row["columnName"]
// insert the list object
}
}
}
Refer to this one:
Inserting Data from SQL Server to Sqlite

C# reading values from datatable filled with sql select

I am coding win form app, which checks on startup right of the currently logged user. I had these right saved in MS SQL server in the table. When importing data to Datatable, there is no problem. But when I want to read value, there is message "cannot find column xy".
SqlDataAdapter sdaRights = new SqlDataAdapter("SELECT * FROM rights WHERE [user]='" + System.Security.Principal.WindowsIdentity.GetCurrent().Name + "'", conn);
DataTable dtRights = new DataTable(); //this is creating a virtual table
sdaRights.Fill(dtRights);
Object cellValue = dt.Rows[0][1];
int value = Convert.ToInt32(cellValue);
MessageBox.Show(value.ToString());
I would like, that program would save the value from SQL to int.

You are assuming that you have rows being returned, would be my first guess. You should loop through your DataTable instead of simply trying to access element 0 in it.
DataTable dtRights = new DataTable();
sdaRights.Fill(dtRights);
foreach(DataRow row in dtRights.Rows) {
Object cellValue = row[1];
int value = Convert.ToInt32(cellValue);
MessageBox.Show(value.ToString());
}

using (SqlConnection con = new SqlConnection("your connection string"))
{
using (SqlCommand cmd = new SqlCommand("SELECT [column_you_want] FROM [rights] WHERE [user] = #user"))
{
cmd.Parameters.AddWithValue("#user", System.Security.Principal.WindowsIdentity.GetCurrent().Name);
con.Open();
int right = Convert.ToInt32(cmd.ExecuteScalar());
}
}

Sqlite DataAdapter isn't updating when called

I have to write identical tables to two different Sqlite database. The tables rewrite existing data and ids, so I currently just delete the entire table and rewrite. Depending on the order that I write to the db, the C# SQLiteCommandBuilder does not update the second db called.
If I call Db_A before Db_B, then A gets written and B gets deleted and vice versa. Can anyone tell me why the second table enters the code to get deleted, but the Sqlite adapter never updates the second table? It doesn't throw an error either.
public static bool WriteDt_Name(DataTable dt)
{
using (connA = GetDbAConn())
{
SaveDataTable(connA, dt);
}
using (connB = GetDbBConn())
{
SaveDataTable(connB, dt);
}
return true;
}
public static void SaveDataTable(SQLiteConnection conn, DataTable dt)
{
string table = dt.TableName;
var cmd = conn.CreateCommand();
cmd.CommandText = string.Format("DELETE FROM {0}", table);
int val = cmd.ExecuteNonQuery();
cmd.CommandText = string.Format("SELECT * FROM {0}", table);
using (var adapter = new SQLiteDataAdapter(cmd))
{
using (SQLiteCommandBuilder builder = new SQLiteCommandBuilder(adapter))
{
adapter.Update(dt);
conn.Close();
}
}
}
public static SQLiteConnection GetDbAConn()
{
string base_dir = System.AppDomain.CurrentDomain.BaseDirectory;
string path = Directory.GetParent(Directory.GetParent(Directory.GetParent(Directory.GetParent(Directory.GetParent(base_dir).ToString()).ToString()).ToString()).ToString()).ToString();
path = path + "\\db\\DbA.sqlite;";
SQLiteConnection conn = new SQLiteConnection("Data Source=" + path + "Version=3;");
return conn;
}
I have tried splitting SaveDataTable into a SaveDt_A and SaveDt_B and calling it that way. I still get the same result.

Connection to SQL Server through ADO.NET - Empty Listbox

Trying to set up a connection to my local SQL Server Express instance so that I can display columns in a listbox. Th build runs fine and I can't see errors, but there is no data in the listbox. I have tested the query and that is fine. I am using NT Authentication to the database. Any ideas where I might have gone wrong?
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void customers_SelectedIndexChanged(object sender, EventArgs e)
{
string commstring = "Driver ={SQL Server}; Server = DESKTOP-5T4MHHR\\SQLEXPRESS; Database = AdventureWorks2014; Trusted_Connection = Yes;";
string connstring = "SELECT FirstName, LastName FROM Person.Person";
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(commstring, connstring);
DataSet customerDataSet = new DataSet();
customerDataAdapater.Fill(customerDataSet, "Person.Person");
DataTable customerDataTable = new DataTable();
customerDataTable = customerDataSet.Tables[0];
foreach (DataRow dataRow in customerDataTable.Rows)
{
customers.Items.Add(dataRow["FirstName"] + " (" + dataRow["LastName"] + ")");
}
}
}

I tested your code in a sample project here and I realized you passed the parameters to SqlDataAdapter constructor in a wrong order.
After changing the follow line:
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(commstring, connstring);
by
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(connstring, commstring);
the listbox was filled successfully.

Your connection string seems weird.....
Could you try using just this:
string commstring = "Server=DESKTOP-5T4MHHR\\SQLEXPRESS;Database=AdventureWorks2014;Trusted_Connection=Yes;";
Also: why are you first creating a DataSet, filling in a single set of data, and then extracting a DataTable from it?? This is unnecessarily complicated code - just use this instead:
SqlDataAdapter customerDataAdapater = new SqlDataAdapter(commstring, connstring);
// if you only ever need *one* set of data - just use a DataTable directly!
DataTable customerDataTable = new DataTable();
// Fill DataTable with the data from the query
customerDataAdapater.Fill(customerDataTable);
Update: I would really rewrite your code to something like this:
// create a separate class - call it whatever you like
public class DataProvider
{
// define a method to provide that data to you
public List<string> GetPeople()
{
// define connection string (I'd really load that from CONFIG, in real world)
string connstring = "Server=MSEDTOP;Database=AdventureWorks2014;Trusted_Connection=Yes;";
// define your query
string query = "SELECT FirstName, LastName FROM Person.Person";
// prepare a variable to hold the results
List<string> entries = new List<string>();
// put your SqlConnection and SqlCommand into "using" blocks
using (SqlConnection conn = new SqlConnection(connstring))
using (SqlCommand cmd = new SqlCommand(query, conn))
{
conn.Open();
// iterate over the results using a SqlDataReader
using (SqlDataReader rdr = cmd.ExecuteReader())
{
while (rdr.Read())
{
// get first and last name from current row of query
string firstName = rdr.GetFieldValue<string>(0);
string lastName = rdr.GetFieldValue<string>(1);
// add entry to result list
entries.Add(firstName + " " + lastName);
}
rdr.Close();
}
conn.Close();
}
// return the results
return entries;
}
}
And in your code-behind, you only need to do something like this:
protected override void OnLoad(.....)
{
if (!IsPostback)
{
List<string> people = new DataProvider().GetPeople();
customers.DataSource = people;
customers.DataBind();
}
}
but I still don't understand what you were trying to when the SelectedIndexChanged event happens.....