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)。
--Create DataBase create database BulkTestDB; Go use BulkTestDB; go --Create Table Create table BulkTestTable( Id int primary key, UserName nvarchar(32), Pwd varchar(16)) go --Create Table Valued CREATE 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SQL sqlComm.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:
[c-sharp] view plain copy 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。
时间: 2024-10-10 19:19:43