What’s the best way to bulk database inserts from c#?

Question

CsharperGuyInLondon, here's a simple example of SqlBulkCopy code:

using System.Data.SqlClient;

DataTable table = new DataTable("States");
// construct DataTable
table.Columns.Add(new DataColumn("id_state", typeof(int))); 
table.Columns.Add(new DataColumn("state_name", typeof(string)));

// note: if "id_state" is defined as an identity column in your DB,
// row values for that column will be ignored during the bulk copy
table.Rows.Add("1", "Atlanta");
table.Rows.Add("2", "Chicago");
table.Rows.Add("3", "Springfield");

using(SqlBulkCopy bulkCopy = new SqlBulkCopy(connectionString))
{
  bulkCopy.BulkCopyTimeout = 600; // in seconds
  bulkCopy.DestinationTableName = "state";
  bulkCopy.WriteToServer(table);
}

Well, 10 items isn't what I call bulk, but for larger sets, SqlBulkCopy is your friend. All you need to do is feed it either a DataTable or an IDataReader (my preferred option, 'cos I like streaming APIs). I did something similar here (you can ignore the xml side - just subclass the SimpleDataReader).

The .NET SqlBulkCopy class works quite well.

Re the solution for SqlBulkCopy, I created a class than takes Datatable or a List<T> and a Buffer size (CommitBatchSize). It will convert the list to a data table using an extension (in the second class).

It works very fast. On my PC, I am able to insert more than 10 million complicated records in less than 10 seconds.

Here is the class:

using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DAL
{

public class BulkUploadToSql<T>
{
    public IList<T> InternalStore { get; set; }
    public string TableName { get; set; }
    public int CommitBatchSize { get; set; }=1000;
    public string ConnectionString { get; set; }

    public void Commit()
    {
        if (InternalStore.Count>0)
        {
            DataTable dt;
            int numberOfPages = (InternalStore.Count / CommitBatchSize)  + (InternalStore.Count % CommitBatchSize == 0 ? 0 : 1);
            for (int pageIndex = 0; pageIndex < numberOfPages; pageIndex++)
                {
                    dt= InternalStore.Skip(pageIndex * CommitBatchSize).Take(CommitBatchSize).ToDataTable();
                BulkInsert(dt);
                }
        } 
    }

    public void BulkInsert(DataTable dt)
    {
        using (SqlConnection connection = new SqlConnection(ConnectionString))
        {
            // make sure to enable triggers
            // more on triggers in next post
            SqlBulkCopy bulkCopy =
                new SqlBulkCopy
                (
                connection,
                SqlBulkCopyOptions.TableLock |
                SqlBulkCopyOptions.FireTriggers |
                SqlBulkCopyOptions.UseInternalTransaction,
                null
                );

            // set the destination table name
            bulkCopy.DestinationTableName = TableName;
            connection.Open();

            // write the data in the "dataTable"
            bulkCopy.WriteToServer(dt);
            connection.Close();
        }
        // reset
        //this.dataTable.Clear();
    }

}

public static class BulkUploadToSqlHelper
{
    public static DataTable ToDataTable<T>(this IEnumerable<T> data)
    {
        PropertyDescriptorCollection properties =
            TypeDescriptor.GetProperties(typeof(T));
        DataTable table = new DataTable();
        foreach (PropertyDescriptor prop in properties)
            table.Columns.Add(prop.Name, Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);
        foreach (T item in data)
        {
            DataRow row = table.NewRow();
            foreach (PropertyDescriptor prop in properties)
                row[prop.Name] = prop.GetValue(item) ?? DBNull.Value;
            table.Rows.Add(row);
        }
        return table;
    }
}

}

Here is an example when I want to insert a List of my custom object List<PuckDetection> (ListDetections):

var objBulk = new BulkUploadToSql<PuckDetection>()
{
        InternalStore = ListDetections,
        TableName= "PuckDetections",
        CommitBatchSize=1000,
        ConnectionString="ENTER YOU CONNECTION STRING"
};
objBulk.Commit();

You can build a BLOB (image) and send it as a parameter to a stored procedure. Inside the stored procedure, you can fetch all the items using substring().

Here's a good example of SqlBulkCopy in action:

http://blogs.msdn.com/nikhilsi/archive/2008/06/11/bulk-insert-into-sql-from-c-app.aspx

I construct the list as an xml string and pass it to the stored proc. In SQL 2005, it has enhanced xml functionalities to parse the xml and do a bulk insert.

check this post: Passing lists to SQL Server 2005 with XML Parameters