SqlBulkCopyColumnMapping

SqlBulkCopyColumnMapping

自曾列就别往下看 别折腾了  

使用 SqlBulkCopy ,dataTable 必须跟sql里面的表字段完全一样

下面在sqlserver中演示

mysql 请google MySqlBulkLoader

oracle 请google OracleBulkCopy

表结构

        DROP TABLE [dbo].[Product]
GO
CREATE TABLE [dbo].[Product] (
[Id] varchar(36) NOT NULL ,
[Name] varchar(255) NOT NULL ,
[Price] decimal(18,4) NOT NULL
)
GO
ALTER TABLE [dbo].[Product] ADD PRIMARY KEY ([Id])
GO

批量添加

        public static void Insert<T>(string connectionString, List<T> dataList, string destinationTableName, int batchSize = )
{
DataTable dataTable = ConvertToDataTable(dataList);
Insert(connectionString, dataTable, destinationTableName, batchSize);
} public static void Insert(string connectionString, DataTable dataTable, string destinationTableName, int batchSize = )
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
if (connection.State != ConnectionState.Open)
{
connection.Open();
}
using (SqlTransaction transaction = connection.BeginTransaction())
{
using (SqlBulkCopy bulkCopy = new SqlBulkCopy(connection, SqlBulkCopyOptions.Default, transaction))
{
bulkCopy.BatchSize = batchSize;
bulkCopy.DestinationTableName = destinationTableName;
try
{
bulkCopy.WriteToServer(dataTable);
transaction.Commit();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
transaction.Rollback();
}
}
}
}
}

批量添加测试代码

public static void Insert()
{
List<Product> products = new List<Product>();
for (int i = ; i < ; i++)
{
Product product = new Product
{
Id = Guid.NewGuid().ToString(),
Name = $"商品{i}",
Price = (decimal)i
};
products.Add(product);
}
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
Insert(SqLiteHelper.SqlServerConnection, products, "Product");
stopwatch.Stop();
Console.WriteLine("耗时:" + stopwatch.ElapsedMilliseconds);
}

批量更新

public static void Update<T>(string connectionString, List<T> list, string destinationTableName)
{
var dt = ConvertToDataTable(list);
using (SqlConnection connection = new SqlConnection(connectionString))
{
if (connection.State != ConnectionState.Open)
{
connection.Open();
}
using (SqlTransaction transaction = connection.BeginTransaction())
{
using (SqlCommand command = new SqlCommand(string.Empty, connection))
{
try
{
command.Transaction = transaction;
command.CommandText = "CREATE TABLE #TmpTable(Id varchar(36),Name varchar(255),Price decimal(18,4))";
command.ExecuteNonQuery();
using (SqlBulkCopy bulkCopy = new SqlBulkCopy(connection, SqlBulkCopyOptions.Default, transaction))
{
bulkCopy.BulkCopyTimeout = ;
bulkCopy.DestinationTableName = "#TmpTable";
bulkCopy.WriteToServer(dt);
bulkCopy.Close();
}
command.CommandTimeout = ;
command.CommandText = "UPDATE T SET T.Name =Temp.Name FROM " + destinationTableName + " T INNER JOIN #TmpTable Temp ON T.Id=Temp.Id; DROP TABLE #TmpTable;";
command.ExecuteNonQuery();
transaction.Commit();
}
catch (Exception)
{
transaction.Rollback();
}
}
}
}
}

批量更新测试代码

        public static List<string> GetList()
{
List<string> list = new List<string>();
using (SqlConnection conn = new SqlConnection(SqLiteHelper.SqlServerConnection))
{
using (SqlCommand command = new SqlCommand("SELECT TOP 5000 Id FROM Product", conn))
{
conn.Open();
var data = command.ExecuteReader();
while (data.Read())
{
list.Add(data["Id"].ToString());
}
}
} return list;
} public static void Update()
{
var list = GetList();
List<Product> products = new List<Product>();
for (int i = ; i < list.Count; i++)
{
Product product = new Product
{
Id = list[i],
Name = $"默认{i}",
Price = (decimal)i *
};
products.Add(product);
}
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
Update(SqLiteHelper.SqlServerConnection, products, "Product");
stopwatch.Stop();
Console.WriteLine("耗时:" + stopwatch.ElapsedMilliseconds);
}

List转DataTable

 public static DataTable ConvertToDataTable<T>(IList<T> data)
{
PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(typeof(T));
DataTable table = new DataTable();
foreach (PropertyDescriptor prop in properties)
{
table.Columns.Add(prop.Name, Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);
}
foreach (T item in data)
{
DataRow row = table.NewRow();
foreach (PropertyDescriptor prop in properties)
{
row[prop.Name] = prop.GetValue(item) ?? DBNull.Value;
}
table.Rows.Add(row);
}
return table;
}

实体类

 public class Product
{
public string Id { get; set; } public string Name { get; set; } public decimal Price { get; set; }
}

链接字符串配置

 public class SqLiteHelper
{
public const string SqlServerConnection = "Data Source=IP;Initial Catalog=库名;uid=帐号;pwd=密码;MultipleActiveResultSets=True";
}

测试了一下 添加10W 差不多 10S左右

补充一个 多表操作

public static void Inserts(string connectionString, Dictionary<string, DataTable> dataTables, int batchSize = )
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
if (connection.State != ConnectionState.Open)
{
connection.Open();
}
using (SqlTransaction transaction = connection.BeginTransaction())
{
try
{
foreach (var item in dataTables)
{
using (SqlBulkCopy bulkCopy = new SqlBulkCopy(connection, SqlBulkCopyOptions.Default, transaction))
{
bulkCopy.BatchSize = batchSize;
bulkCopy.DestinationTableName = item.Key;
bulkCopy.WriteToServer(item.Value);
}
}
transaction.Commit();
}
catch (Exception ex)
{ Console.WriteLine(ex.Message);
transaction.Rollback();
}
}
}
}

测试代码

public static void Inserts()
{
const int count = ;
List<Order> orders = new List<Order>();
List<Product> products = new List<Product>();
for (var i = ; i < count; i++)
{
Product product = new Product
{
Id = Guid.NewGuid().ToString(),
Name = $"商品{i}",
Price = i * 0.8M
};
products.Add(product);
Order order = new Order
{
Id = Guid.NewGuid().ToString(),
ProductId = product.Id,
Remake = "suggestions",
Status =
};
orders.Add(order);
}
var productsDataTable = Batch.ConvertToDataTable(products);
var ordersDataTable = Batch.ConvertToDataTable(orders);
Dictionary<string, DataTable> dataTables = new Dictionary<string, DataTable>
{ { "Product", productsDataTable},
{ "Orders",ordersDataTable}
}; Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
Inserts(SqLiteHelper.SqlServerConnection, dataTables);
stopwatch.Stop();
Console.WriteLine("耗时:" + stopwatch.ElapsedMilliseconds);
}

新增订单实体对象

    public class Order
{
public string Id { get; set; } public string ProductId { get; set; } public int Status { get; set; } public string Remake { get; set; }
}

Order表结构

DROP TABLE [dbo].[Orders]
GO
CREATE TABLE [dbo].[Orders] (
[Id] varchar(36) NOT NULL ,
[ProductId] varchar(36) NOT NULL ,
[Status] int NOT NULL ,
[Remake] varchar(255) NOT NULL
) GO ALTER TABLE [dbo].[Orders] ADD PRIMARY KEY ([Id])
GO

批量删除也贴一个吧

  public void BatchDelete<T>(List<T> idList)
{
var type = typeof(T);
var id = GetProperties(type);
var innerJoin = $"a.{id}=b.{id}";
var tempTableName = $"#TmpTable{type.Name}";
var dataTableName = BulkCopyRepositoryExtension.GetTableName(type);
var sqlConnection = (SqlConnection)_unit.Connection;
var sqlTransaction = (SqlTransaction)_unit.Transaction;
var sqlCommand = (SqlCommand)_unit.Command;
sqlCommand.CommandText = $"SELECT * INTO {tempTableName} FROM {dataTableName} WHERE 1 = 2";
sqlCommand.ExecuteNonQuery();
using (SqlBulkCopy bulkCopy = new SqlBulkCopy(sqlConnection, SqlBulkCopyOptions.Default, sqlTransaction))
{
bulkCopy.DestinationTableName = tempTableName;
using (var reader = new ObjectReader(type, idList, BulkCopyRepositoryExtension.GetFields(type)))
{
bulkCopy.WriteToServer(reader);
}
}
sqlCommand.CommandText = $"DELETE a FROM {dataTableName} AS a INNER JOIN {tempTableName} AS b ON {innerJoin}; DROP TABLE {tempTableName};";
sqlCommand.ExecuteNonQuery();

批量删除关键代码已贴上  如需全部代码 QQ群 4816230869

为了满足关注粉丝的要求贴上说明

1、SqlBulkCopy类的构造方法

其中: conn表示一个SqlConnection对象

connStr表示数据库连接字符串

  1. SqlBulkCopy(conn)
  2. SqlBulkCopy(connStr)
  3. SqlBulkCopy(connStr, SqlBulkCopyOptions copyOptions)
  4. SqlBulkCopy(conn, SqlBulkCopyOptions copyOptions, SqlTransaction externalTransaction)

其中还有几个陌生的对象:SqlBulkCopyOptions 和 SqlTransaction

1.1、SqlBulkCopyOptions类

这个类是一个枚举类型:

对象备注
Default0 
KeepIdentity1保留源标识值。
如果未指定,则由目标分配标识值。
CheckConstraints2在插入数据的同时检查约束。
默认情况下,不检查约束。
TableLock4在批量复制操作期间获取批量更新锁。
如果未指定,则使用行锁。
KeepNulls8保留目标表中的空值,而不管默认值的设置如何。
如果未指定,则空值将由默认值替换(如果适用)
FireTriggers16指定后,会导致服务器为插入到数据库中的行激发插入触发器。
UseInternalTransaction32

如果已指定,则每一批批量复制操作将在事务中进行。

如果指示了此选项,并且为构造函数提供了 System.Data.SqlClient.SqlTransaction对象,则发生 System.ArgumentException(参数异常)。因为两个事务冲突了。

1.2、SqlTransaction类

这个类是事务类,是个密封类,实现了DbTransaction抽象类

2、SqlBulkCopy类的常用属性

属性名功能备注
BatchSize设置或获取每达到多少行就更新到服务器(也就是目标表)值为int,
BulkCopyTimeout设置或获取超时时间默认30秒,如果设置成0,将无限制等待,
值为int,单位为秒
DestinationTableName设置或获取服务器上的目标表的名称也就是批量更新的目标表,
值为String类型
EnableStreaming设置或获取是否支持传输 IDataReader 对象的数据true为支持,
值为bool类型
NotifyAfter设置或获取在生成通知事件之前要处理的行数默认为0,
值为int类型,
ColumnMappings获取列映射定义数据源中的列和目标表中的列之间的映射关系返回值为SqlBulkCopyColumnMappingCollection

2.1、表中的SqlBulkCopyColumnMappingCollection类型是一个映射集合类,是目标表的列和源表的列的映射关系的集合。

这个类是一个密封类,不能被继承,实现了一个CollectionBase抽象类。

SqlBulkCopyColumnMappingCollection没有提供构造方法,我们也不需要去newat的对象,主要是使用它的几个重载的Add()方法

Add()有五个重载的方法:

  • SqlBulkCopyColumnMapping Add(SqlBulkCopyColumnMapping bulkCopyColumnMapping);
  • SqlBulkCopyColumnMapping Add(string sourceColumn, string destinationColumn);
  • SqlBulkCopyColumnMapping Add(int sourceColumnIndex, string destinationColumn);
  • SqlBulkCopyColumnMapping Add(string sourceColumn, int destinationColumnIndex);
  • SqlBulkCopyColumnMapping Add(int sourceColumnIndex, int destinationColumnIndex);

其中四个方法是类似的,都是对应的列名或者列的位置。

第一个方法是添加一个已经构建好的SqlBulkCopyColumnMapping对象,

他也有集合常用的方法:

方法名功能备注
Clear();清除集合中的映射关系 
Contains(SqlBulkCopyColumnMapping value);判断是否包含指定映射关系 
IndexOf(SqlBulkCopyColumnMapping value);返回指定映射关系的位置 
Remove(SqlBulkCopyColumnMapping value);移除指定映射关系 
RemoveAt(int index);移除指定位置的映射关系 
Insert(int index, SqlBulkCopyColumnMapping value);在指定位置插入映射关系 
CopyTo(SqlBulkCopyColumnMapping[] array, int index);从指定位置开始将映射关系复制到指定数组中index指定的集合中的位置,
而不是数组中的角标

3、SqlBulkCopy类的常用方法

  • WriteToServer,这个方法重载了四次,功能是将数据写到目的表中。
WriteToServer(DataRow[] rows);将 DataRow 数组所有元素写到目标表中
WriteToServer(DataTable table);将 DataTable 所有行写到目标表中
WriteToServer(IDataReader reader);将指定的 IDataReader 对象中的数据写到目标表中
WriteToServer(DataTable table, DataRowState rowState);将 DataTable 中指定状态的所有行写到目标表中

【上表中的 DataRowState 状态行可以参考这篇博客DataTable的AcceptChanges()方法和DataRow的RowState属性

04-15 08:16