我正在寻找插入实体框架的最快方法。
我之所以问这个问题,是因为您有一个活动的TransactionScope,并且插入量很大(4000+)。它可能会持续超过10分钟(事务的默认超时),这将导致事务不完整。
我正在寻找插入实体框架的最快方法。
我之所以问这个问题,是因为您有一个活动的TransactionScope,并且插入量很大(4000+)。它可能会持续超过10分钟(事务的默认超时),这将导致事务不完整。
当前回答
因为这里从未提到过,我想在这里重新推荐EFCore.BulkExtensions
context.BulkInsert(entitiesList); context.BulkInsertAsync(entitiesList);
context.BulkUpdate(entitiesList); context.BulkUpdateAsync(entitiesList);
context.BulkDelete(entitiesList); context.BulkDeleteAsync(entitiesList);
context.BulkInsertOrUpdate(entitiesList); context.BulkInsertOrUpdateAsync(entitiesList); // Upsert
context.BulkInsertOrUpdateOrDelete(entitiesList); context.BulkInsertOrUpdateOrDeleteAsync(entitiesList); // Sync
context.BulkRead(entitiesList); context.BulkReadAsync(entitiesList);
其他回答
我对上面的@Slauma示例进行了一个通用扩展;
public static class DataExtensions
{
public static DbContext AddToContext<T>(this DbContext context, object entity, int count, int commitCount, bool recreateContext, Func<DbContext> contextCreator)
{
context.Set(typeof(T)).Add((T)entity);
if (count % commitCount == 0)
{
context.SaveChanges();
if (recreateContext)
{
context.Dispose();
context = contextCreator.Invoke();
context.Configuration.AutoDetectChangesEnabled = false;
}
}
return context;
}
}
用法:
public void AddEntities(List<YourEntity> entities)
{
using (var transactionScope = new TransactionScope())
{
DbContext context = new YourContext();
int count = 0;
foreach (var entity in entities)
{
++count;
context = context.AddToContext<TenancyNote>(entity, count, 100, true,
() => new YourContext());
}
context.SaveChanges();
transactionScope.Complete();
}
}
据我所知,EntityFramework中没有BulkInsert来提高大型插件的性能。
在这种情况下,您可以使用ADO.net中的SqlBulkCopy来解决问题
但是,对于超过(+4000)个插入,我建议使用存储过程。附上经过的时间。我确实插入了20英寸的11.788行
这就是代码
public void InsertDataBase(MyEntity entity)
{
repository.Database.ExecuteSqlCommand("sp_mystored " +
"@param1, @param2"
new SqlParameter("@param1", entity.property1),
new SqlParameter("@param2", entity.property2));
}
使用SqlBulkCopy:
void BulkInsert(GpsReceiverTrack[] gpsReceiverTracks)
{
if (gpsReceiverTracks == null)
{
throw new ArgumentNullException(nameof(gpsReceiverTracks));
}
DataTable dataTable = new DataTable("GpsReceiverTracks");
dataTable.Columns.Add("ID", typeof(int));
dataTable.Columns.Add("DownloadedTrackID", typeof(int));
dataTable.Columns.Add("Time", typeof(TimeSpan));
dataTable.Columns.Add("Latitude", typeof(double));
dataTable.Columns.Add("Longitude", typeof(double));
dataTable.Columns.Add("Altitude", typeof(double));
for (int i = 0; i < gpsReceiverTracks.Length; i++)
{
dataTable.Rows.Add
(
new object[]
{
gpsReceiverTracks[i].ID,
gpsReceiverTracks[i].DownloadedTrackID,
gpsReceiverTracks[i].Time,
gpsReceiverTracks[i].Latitude,
gpsReceiverTracks[i].Longitude,
gpsReceiverTracks[i].Altitude
}
);
}
string connectionString = (new TeamTrackerEntities()).Database.Connection.ConnectionString;
using (var connection = new SqlConnection(connectionString))
{
connection.Open();
using (var transaction = connection.BeginTransaction())
{
using (var sqlBulkCopy = new SqlBulkCopy(connection, SqlBulkCopyOptions.TableLock, transaction))
{
sqlBulkCopy.DestinationTableName = dataTable.TableName;
foreach (DataColumn column in dataTable.Columns)
{
sqlBulkCopy.ColumnMappings.Add(column.ColumnName, column.ColumnName);
}
sqlBulkCopy.WriteToServer(dataTable);
}
transaction.Commit();
}
}
return;
}
记下几点,这是我的实施,我的改进以及其他回答和评论。
改进:
从我的实体获取SQL连接字符串仅在某些部分使用SQLBulk,其余部分仅使用实体框架使用与SQL数据库相同的日期表列名,无需映射每个列使用与SQL Datatable相同的Datatable名称public void InsertBulkDatatable(DataTable数据表){EntityConnectionStringBuilder entityBuilder=新的EntityConnectionStringBuilder(ConfigurationManager.ConnectionStrings[“MyDbContextConnectionName”].ConnectionString);string cs=entityBuilder.ProviderConnectionString;使用(varconnection=newSqlConnection(cs)){SqlTransaction事务=null;connection.Open();尝试{transaction=connection.BegginTransaction();使用(var sqlBulkCopy=新的sqlBulkCopy(连接,SqlBulkCopyOptions.TableLock,事务)){sqlBulkCopy.DestinationTableName=dataTable.TableName//使用SQL数据表在c中命名数据表#//映射列foreach(dataTable.Columns中的DataColumn列){sqlBulkCopy.ColumnMappings.Add(column.ColumnName,column.ColumnName);}sqlBulkCopy.WriteToServer(数据表);}transaction.Commit();}catch(异常){transaction.Rollback();}}}