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在SQL Server 中插入一条数据使用Insert语句,但是如果想要批量插入一堆数据的话,循环使用Insert不仅效率低,而且会导致SQL一系统性能问题。下面介绍SQL Server支持的两种批量数据插入方法:Bulk和表值参数(Table-Valued Parameters)。
运行下面的脚本,建立测试数据库和表值参数。
--Create DataBasecreate database BulkTestDB;gouse BulkTestDB;go--Create TableCreate table BulkTestTable(Id int primary key,UserName nvarchar(32),Pwd varchar(16))go--Create Table ValuedCREATE TYPE BulkUdt AS TABLE(Id int,UserName nvarchar(32),Pwd varchar(16))
下面我们使用最简单的Insert语句来插入100万条数据,代码如下:
Stopwatch sw = new Stopwatch();SqlConnection sqlConn = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnStr"].ConnectionString);//连接数据库SqlCommand sqlComm = new SqlCommand();sqlComm.CommandText = string.Format("insert into BulkTestTable(Id,UserName,Pwd)values(@p0,@p1,@p2)");//参数化SQLsqlComm.Parameters.Add("@p0", SqlDbType.Int);sqlComm.Parameters.Add("@p1", SqlDbType.NVarChar);sqlComm.Parameters.Add("@p2", SqlDbType.VarChar);sqlComm.CommandType = CommandType.Text;sqlComm.Connection = sqlConn;sqlConn.Open();try{//循环插入100万条数据,每次插入10万条,插入10次。for (int multiply = 0; multiply < 10; multiply++){for (int count = multiply * 100000; count < (multiply + 1) * 100000; count++){sqlComm.Parameters["@p0"].Value = count;sqlComm.Parameters["@p1"].Value = string.Format("User-{0}", count * multiply);sqlComm.Parameters["@p2"].Value = string.Format("Pwd-{0}", count * multiply);sw.Start();sqlComm.ExecuteNonQuery();sw.Stop();}//每插入10万条数据后,显示此次插入所用时间Console.WriteLine(string.Format("Elapsed Time is {0} Milliseconds", sw.ElapsedMilliseconds));}}catch (Exception ex){throw ex;}finally{sqlConn.Close();}Console.ReadLine();
耗时图如下:
由于运行过慢,才插入10万条就耗时72390 milliseconds,所以我就手动强行停止了。
下面看一下使用Bulk插入的情况:
bulk方法主要思想是通过在客户端把数据都缓存在Table中,然后利用SqlBulkCopy一次性把Table中的数据插入到数据库
代码如下:
public static void BulkToDB(DataTable dt){SqlConnection sqlConn = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnStr"].ConnectionString);SqlBulkCopy bulkCopy = new SqlBulkCopy(sqlConn);bulkCopy.DestinationTableName = "BulkTestTable";bulkCopy.BatchSize = dt.Rows.Count;try{sqlConn.Open();if (dt != null && dt.Rows.Count != 0)bulkCopy.WriteToServer(dt);}catch (Exception ex){throw ex;}finally{sqlConn.Close();if (bulkCopy != null)bulkCopy.Close();}}public static DataTable GetTableSchema(){DataTable dt = new DataTable();dt.Columns.AddRange(new DataColumn[]{new DataColumn("Id",typeof(int)),new DataColumn("UserName",typeof(string)),new DataColumn("Pwd",typeof(string))});return dt;}static void Main(string[] args){Stopwatch sw = new Stopwatch();for (int multiply = 0; multiply < 10; multiply++){DataTable dt = Bulk.GetTableSchema();for (int count = multiply * 100000; count < (multiply + 1) * 100000; count++){DataRow r = dt.NewRow();r[0] = count;r[1] = string.Format("User-{0}", count * multiply);r[2] = string.Format("Pwd-{0}", count * multiply);dt.Rows.Add(r);}sw.Start();Bulk.BulkToDB(dt);sw.Stop();Console.WriteLine(string.Format("Elapsed Time is {0} Milliseconds", sw.ElapsedMilliseconds));}Console.ReadLine();}
耗时图如下:
可见,使用Bulk后,效率和性能明显上升。使用Insert插入10万数据耗时72390,而现在使用Bulk插入100万数据才耗时17583。
最后再看看使用表值参数的效率,会另你大为惊讶的。
表值参数是SQL Server 2008新特性,简称TVPs。对于表值参数不熟悉的朋友,可以参考最新的book online,我也会另外写一篇关于表值参数的博客,不过此次不对表值参数的概念做过多的介绍。言归正传,看代码:
public static void TableValuedToDB(DataTable dt){SqlConnection sqlConn = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnStr"].ConnectionString);const string TSqlStatement ="insert into BulkTestTable (Id,UserName,Pwd)" +" SELECT nc.Id, nc.UserName,nc.Pwd" +" FROM @NewBulkTestTvp AS nc";SqlCommand cmd = new SqlCommand(TSqlStatement, sqlConn);SqlParameter catParam = cmd.Parameters.AddWithValue("@NewBulkTestTvp", dt);catParam.SqlDbType = SqlDbType.Structured;//表值参数的名字叫BulkUdt,在上面的建立测试环境的SQL中有。catParam.TypeName = "dbo.BulkUdt";try{sqlConn.Open();if (dt != null && dt.Rows.Count != 0){cmd.ExecuteNonQuery();}}catch (Exception ex){throw ex;}finally{sqlConn.Close();}}public static DataTable GetTableSchema(){DataTable dt = new DataTable();dt.Columns.AddRange(new DataColumn[]{new DataColumn("Id",typeof(int)),new DataColumn("UserName",typeof(string)),new DataColumn("Pwd",typeof(string))});return dt;}static void Main(string[] args){Stopwatch sw = new Stopwatch();for (int multiply = 0; multiply < 10; multiply++){DataTable dt = TableValued.GetTableSchema();for (int count = multiply * 100000; count < (multiply + 1) * 100000; count++){ DataRow r = dt.NewRow();r[0] = count;r[1] = string.Format("User-{0}", count * multiply);r[2] = string.Format("Pwd-{0}", count * multiply);dt.Rows.Add(r);}sw.Start();TableValued.TableValuedToDB(dt);sw.Stop();Console.WriteLine(string.Format("Elapsed Time is {0} Milliseconds", sw.ElapsedMilliseconds));}Console.ReadLine();}
耗时图如下:
比Bulk还快5秒。
如需转载,请注明此文原创自CSDN TJVictor专栏:http://blog.csdn.net/tjvictor/archive/2009/07/18/4360030.aspx |
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