以下内容大部分来自:
http://blog.****.net/tjvictor/article/details/4360030
部分内容出自互联网,实验结果为亲测。
最近自己开发一个向数据库中插入大量历史数据的函数库,需要解决一个大数据量插入的效率问题。不用分析,我知道如果采取逐条数据插入的方式,那么效率肯定很低,光是那么多循环就知道很慢了。于是乎,我找到了上篇博客,知道了BulkCopy和TVPs方式。为了更好的了解其效率,我自己动手亲测了一下效果,测试的数据库位于本机。
(1)方式1:循环插入
public static void NormalInerst(String connString)
{
Console.WriteLine("使用NNormalInerst方式:");
Stopwatch sw = new Stopwatch();
SqlConnection sqlConn = new SqlConnection(connString);
SqlCommand sqlCmd = new SqlCommand();
sqlCmd.CommandText = String.Format("insert into BulkTestTable(Id,UserName,Pwd)values(@p0,@p1,@p2)");
sqlCmd.Parameters.Add("@p0", SqlDbType.Int);
sqlCmd.Parameters.Add("@p1", SqlDbType.NVarChar);
sqlCmd.Parameters.Add("@p2", SqlDbType.VarChar);
sqlCmd.CommandType = CommandType.Text;
sqlCmd.Connection = sqlConn;
sqlConn.Open();
try
{
for (int i = , j = ; i < ; ++i )
{
for (j = i * ; j < (i + ) * ; ++j )
{
sqlCmd.Parameters["@p0"].Value = j;
sqlCmd.Parameters["@p1"].Value = String.Format("User-{0}", i * j);
sqlCmd.Parameters["@p2"].Value = String.Format("Pwd-{0}", i * j);
sw.Start();
sqlCmd.ExecuteNonQuery();
sw.Stop();
} Console.WriteLine("第{0}次插入{1}条数据耗时:{2}", (i + ), dataScale, sw.ElapsedMilliseconds);
sw.Reset();
}
}
catch (System.Exception ex)
{
throw ex;
}
finally
{
sqlConn.Close();
}
}
该方式的效率极低,运行时间很长,我这里就不给出结果了,有兴趣可以自己粘贴试一下。PS:其中的数据规模应该是dataScale而不是10000,不过总是还是慢。
(2)方式2:使用BulkCopy
public static void BulkInerst(String connString)
{
Console.WriteLine("使用BulkInerst方式:");
Stopwatch sw = new Stopwatch(); String strDel = "delete from BulkTestTable";
float millTime = ;
for (int multiply = ; multiply < ; multiply++)
{
DataTable dt = GetTableSchema();
for (int count = multiply * dataScale; count < (multiply + ) * dataScale; count++)
{
DataRow r = dt.NewRow();
r[] = count;
r[] = string.Format("User-{0}", count * multiply);
r[] = string.Format("Pwd-{0}", count * multiply);
dt.Rows.Add(r);
} SqlConnection sqlConn = new SqlConnection(connString);
SqlBulkCopy bulkCopy = new SqlBulkCopy(sqlConn);
bulkCopy.DestinationTableName = "BulkTestTable";
bulkCopy.BatchSize = dt.Rows.Count; sw.Reset();
sw.Start();
try
{
sqlConn.Open();
if (dt != null && dt.Rows.Count != )
bulkCopy.WriteToServer(dt);
}
catch (Exception ex)
{
throw ex;
}
finally
{
sqlConn.Close();
if (bulkCopy != null)
bulkCopy.Close();
}
sw.Stop(); Console.WriteLine("第{0}次插入{1}条数据耗时:{2}", (multiply + ), dataScale, sw.ElapsedMilliseconds);
millTime += sw.ElapsedMilliseconds;
}
Console.WriteLine("总耗时:{0}毫秒,平均耗时:{1}毫秒", millTime, millTime / );
SqlConnection sqlConn2 = new SqlConnection(connString);
SqlCommand sqlCmd = new SqlCommand(strDel, sqlConn2);
try
{
sqlConn2.Open();
sqlCmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw ex;
}
finally
{
sqlConn2.Close();
}
Console.WriteLine("Done!");
}
(3)方式3:使用TVPs
public static void TVPsInerst(String connString)
{
Console.WriteLine("使用TVPsInerst方式:");
Stopwatch sw = new Stopwatch();
SqlConnection sqlConn = new SqlConnection(connString);
String strSQL = "insert into BulkTestTable (Id,UserName,Pwd)" +
" SELECT nc.Id, nc.UserName,nc.Pwd" +
" FROM @NewBulkTestTvp AS nc";
String strDel = "delete from BulkTestTable";
float millTime = ; for (int multiply = ; multiply < ; multiply++)
{
DataTable dt = GetTableSchema();
for (int count = multiply * dataScale; count < (multiply + ) * dataScale; count++)
{
DataRow r = dt.NewRow();
r[] = count;
r[] = string.Format("User-{0}", count * multiply);
r[] = string.Format("Pwd-{0}", count * multiply);
dt.Rows.Add(r);
} sw.Reset();
sw.Start();
SqlCommand cmd = new SqlCommand(strSQL, sqlConn);
SqlParameter catParam = cmd.Parameters.AddWithValue("@NewBulkTestTvp", dt);
catParam.SqlDbType = SqlDbType.Structured;
catParam.TypeName = "dbo.BulkUDT";
try
{
sqlConn.Open();
if (dt != null && dt.Rows.Count != )
{
cmd.ExecuteNonQuery();
}
}
catch (Exception ex)
{
throw ex;
}
finally
{
sqlConn.Close();
}
sw.Stop(); Console.WriteLine("第{0}次插入{1}条数据耗时:{2}", (multiply + ), dataScale, sw.ElapsedMilliseconds);
millTime += sw.ElapsedMilliseconds;
}
Console.WriteLine("总耗时:{0}毫秒,平均耗时:{1}毫秒", millTime, millTime / );
SqlCommand sqlCmd = new SqlCommand(strDel, sqlConn);
try
{
sqlConn.Open();
sqlCmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw ex;
}
finally
{
sqlConn.Close();
}
Console.WriteLine("Done!");
}
这里TVPs方式需要利用Visual Studio 2008采用的自定义数据表类型,这是一个比较新的东西。这里补充几个类型和函数,主要是为了检测数据库中是否存在数据表和数据表类型,如果不存在则进行创建。补充代码如下:
public enum CheckType
{
isTable = ,
isType
} protected static int dataScale = ; public static bool CheckExistsObject(String connString, String objectName, CheckType type)
{
String strSQL = "select COUNT(1) from sys.sysobjects where name='" + objectName + "'";
switch (type)
{
case CheckType.isTable:
strSQL = "select COUNT(1) from sys.sysobjects where name='" + objectName + "'";
break;
case CheckType.isType:
strSQL = "select COUNT(1) from sys.types where name='" + objectName + "'";
break;
default:
break;
}
using (SqlConnection conn = new SqlConnection(connString))
{
conn.Open();
SqlCommand cmd = new SqlCommand(strSQL, conn);
int result = Convert.ToInt32(cmd.ExecuteScalar());
if ( == result)
{
return false;
}
} return true;
} public static bool CreateObject(String connString, String objectName, CheckType type)
{
String strSQL = "";
switch (type)
{
case CheckType.isTable:
strSQL = "Create table " + objectName + " (Id int primary key, UserName nvarchar(32), Pwd varchar(16))";
break;
case CheckType.isType:
strSQL = "CREATE TYPE " + objectName + " AS TABLE (Id int, UserName nvarchar(32), Pwd varchar(16))";
break;
default:
break;
}
using (SqlConnection conn = new SqlConnection(connString))
{
conn.Open();
SqlCommand cmd = new SqlCommand(strSQL, conn);
cmd.ExecuteNonQuery();
} return true;
}
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;
}
调用的方式就很好说了,参见如下测试代码:
public static void Main(string[] args)
{
String conString = "Persist Security Info=False;User ID=sa;Password=scbj123!@#;Initial Catalog=testGR;Server=KLH-PC";
String strType = "BulkUDT";
String strTable = "BulkTestTable";
if (!CheckExistsObject(conString, strType, CheckType.isType))
{
Console.WriteLine("类型{0}不存在", strType);
if (CreateObject(conString, strType, CheckType.isType))
{
Console.WriteLine("类型{0}创建成功!", strType);
}
} if (!CheckExistsObject(conString, strTable, CheckType.isTable))
{
Console.WriteLine("表格{0}不存在", strTable);
if (CreateObject(conString, strTable, CheckType.isTable))
{
Console.WriteLine("表格{0}创建成功!", strTable);
}
}
Console.WriteLine("=================================================="); //NormalInerst(conString);
BulkInerst(conString);
TVPsInerst(conString); Console.ReadKey();
}
-------------------------------------------------------------------------------------------------
直接看效果对比:
<1>第一次运行
<2>第二次和第三次运行
这里考虑到了SQL Server自身缓存的原因,所以进行了多次测试,不过数据量没有变。可以从上述结果中看出:TVPs方式不愧是新出的啊,一代更比一代强!