如何在sqlbulkcopy中设置自动映射

Ale*_*kiy 4 c# sql linq

在我们的项目中,我们使用Linq2SQL,但是现在我们需要有可能在数据库表中快速插入近15,000行,因此我编写了一个扩展方法:

public static void BulkInsertBigData(Table<Maintenance> maintenance, IEnumerable<Maintenance> maintenancesToInsert)
    {

            using (var copy = new SqlBulkCopy(maintenance.Context.Connection.ConnectionString, SqlBulkCopyOptions.KeepIdentity | SqlBulkCopyOptions.KeepNulls))
            {
                //copy.ColumnMappings.Add("Id", "Id");
                //copy.ColumnMappings.Add("FacilityId", "FacilityId");
                //copy.ColumnMappings.Add("ParentFacilityId", "ParentFacilityId");
                //copy.ColumnMappings.Add("StartTime", "StartTime");
                //copy.ColumnMappings.Add("EndTime", "EndTime");
                //copy.ColumnMappings.Add("ExpirationTime", "ExpirationTime");
                //copy.ColumnMappings.Add("DispatcherUserName", "DispatcherUserName");
                copy.DestinationTableName = "dbo.Maintenance";
                var data = maintenancesToInsert.ToDataTable();
                copy.WriteToServer(data);
            }

    }
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维护是自动生成的Linq2SQL类。当我取消对ColumnMappings行的注释时,此代码非常有用,但它们不合适,因为如果有人更改dbml,则此代码将无法工作(此代码不敏捷:))。 ToDataTable()是基于反射的方法,它将“维护列表”转换为“数据表”。

如果有任何帮助,我将不胜感激

Mar*_*ell 5

怎么样:

public static void BulkInsertBigData<T>(Table<T> definition, IEnumerable<T> rows)
{
    using (var copy = new SqlBulkCopy(definition.Context.Connection.ConnectionString, SqlBulkCopyOptions.KeepIdentity | SqlBulkCopyOptions.KeepNulls))
    {
        var meta = definition.Context.Mapping.GetMetaType(typeof(T));
        foreach (var col in meta.DataMembers)
        {
            copy.ColumnMappings.Add(col.Member.Name, col.MappedName);
        }
        copy.DestinationTableName = meta.Table.TableName;
        var data = rows.ToDataTable();
        copy.WriteToServer(data);
    }
}
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甚至更好:DataTable通过FastMember取消

public static void BulkInsertBigData<T>(Table<T> definition, IEnumerable<T> rows)
{
    using (var copy = new SqlBulkCopy(definition.Context.Connection.ConnectionString, SqlBulkCopyOptions.KeepIdentity | SqlBulkCopyOptions.KeepNulls))
    {
        var meta = definition.Context.Mapping.GetMetaType(typeof(T));
        var members = new List<string>(meta.DataMembers.Count);
        foreach (var col in meta.DataMembers)
        {
            copy.ColumnMappings.Add(col.Member.Name, col.MappedName);
            members.Add(col.Member.Name);
        }
        copy.DestinationTableName = meta.Table.TableName;
        using (var reader = ObjectReader.Create(rows, members.ToArray()))
        {
            copy.WriteToServer(reader);
        }
    }
}
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