C＃环路和质量插入 [英] C# loops and mass insert

问题描述

后续code将在我的数据库中插入一些值。它得到6个随机值，放东西在一个数组，然后将其插入到数据库中。

The follow code will insert some values in my database. It gets 6 random values, puts the stuff in an array and then inserts it in the database.

    public void LottoTest(object sender, EventArgs e)
    {
        Dictionary<int, int> numbers = new Dictionary<int, int>();
        Random generator = new Random();
        while (numbers.Count < 6)
        {
            numbers[generator.Next(1, 49)] = 1;
        }

        string[] lotto = numbers.Keys.OrderBy(n => n).Select(s => s.ToString()).ToArray();

        foreach (String _str in lotto)
        {
            Response.Write(_str);
            Response.Write(",");
        }


        var connectionstring = "Server=C;Database=lotto;User Id=lottoadmin;Password=password;";

        using (var con = new SqlConnection(connectionstring))  // Create connection with automatic disposal
        {
            con.Open();
            using (var tran = con.BeginTransaction())  // Open a transaction
            {
                // Create command with parameters  (DO NOT PUT VALUES IN LINE!!!!!)
                string sql =
                    "insert into CustomerSelections(val1,val2,val3,val4,val5,val6) values (@val1,@val2,@val3,@val4,@val5,@val6)";
                var cmd = new SqlCommand(sql, con);
                cmd.Parameters.AddWithValue("val1", lotto[0]);
                cmd.Parameters.AddWithValue("val2", lotto[1]);
                cmd.Parameters.AddWithValue("val3", lotto[2]);
                cmd.Parameters.AddWithValue("val4", lotto[3]);
                cmd.Parameters.AddWithValue("val5", lotto[4]);
                cmd.Parameters.AddWithValue("val6", lotto[5]);


                cmd.Transaction = tran;
                cmd.ExecuteNonQuery(); // Insert Record

                tran.Commit();  // commit transaction
                Response.Write("<br />");
                Response.Write("<br />");
                Response.Write("Ticket has been registered!");
            }
        }


    }

什么是循环的最佳方式，并插入MASS条目到数据库中。比方说，通过C＃100000条记录？我希望能够用我的方法来生成随机数和利用，我有太多的插件。

What is the best way to loop and insert MASS entries into the database. Lets say, 100,000 records via C#? I want to be able to generate the random numbers by my method and utilize the insert which i have too..

推荐答案

对于真正大规模的插入， SqlBulkCopy的是你的朋友。最简单的，但低效的方式做，这是刚刚填补了数据表与数据，并抛出，在 SqlBulkCopy的，但它可以通过欺骗的的IDataReader 完成快两倍（相信我，我已经超时的话）。我最近搬到这个code到 FastMember 为了方便，所以你可以这样做：

For true large scale inserts, SqlBulkCopy is your friend. The easy but inefficient way to do this is just to fill a DataTable with the data, and throw that at SqlBulkCopy, but it can be done twice as fast (trust me, I've timed it) by spoofing an IDataReader. I recently moved this code into FastMember for convenience, so you can just do something like:

class YourDataType {
    public int val1 {get;set;}
    public string val2 {get;set;}
    ... etc
    public DateTime val6 {get;set;}
}

然后创建一个迭代器块的（即非缓冲只转发读者）：

then create an iterator block (i.e. a non-buffered forwards only reader):

public IEnumerable<YourDataType> InventSomeData(int count) {
    for(int i = 0 ; i < count ; i++) {
        var obj = new YourDataType {
           ... initialize your random per row values here...
        }
        yield return obj;
    }
}

然后

var data = InventSomeData(1000000);
using(var bcp = new SqlBulkCopy(connection))
using(var reader = ObjectReader.Create(data))
{ // note that you can be more selective with the column map
    bcp.DestinationTableName = "CustomerSelections";
    bcp.WriteToServer(reader);
}

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