SqlBulkCopy简单封装,让批量插入更方便

时间:2021-11-23 06:42:49

关于 SqlServer 批量插入的方式,前段时间也有大神给出了好几种批量插入的方式及对比测试(http://www.cnblogs.com/jiekzou/p/6145550.html),估计大家也都明白,最佳的方式就是用 SqlBulkCopy。自从LZ把Chloe.ORM开源以后,有不少园友/群友询问,框架怎么批量插入数据。我的回答是不支持!最后建议他们用 SqlBulkCopy 的方式插入。在我们公司,我对 SqlBulkCopy 封装成了一个 Helper 方法,使得批量插入更加方便,以满足公司内部不少批量插入需求。我也在群里分享了给他们。因为已经有好几位朋友咨询过,所以,我感觉应该还有很多人还没有自己的一个批量插入方法,因此,LZ今儿给大家分享下我封装的这个批量插入方法,希望大家喜欢。

先看看封装后的方法定义:

SqlBulkCopy简单封装,让批量插入更方便
public static class SqlConnectionExtension
{
    /// <summary>
    /// 使用 SqlBulkCopy 向 destinationTableName 表插入数据
    /// </summary>
    /// <typeparam name="TModel">必须拥有与目标表所有字段对应属性</typeparam>
    /// <param name="conn"></param>
    /// <param name="modelList">要插入的数据</param>
    /// <param name="batchSize">SqlBulkCopy.BatchSize</param>
    /// <param name="destinationTableName">如果为 null,则使用 TModel 名称作为 destinationTableName</param>
    /// <param name="bulkCopyTimeout">SqlBulkCopy.BulkCopyTimeout</param>
    /// <param name="externalTransaction">要使用的事务</param>
    public static void BulkCopy<TModel>(this SqlConnection conn, List<TModel> modelList, int batchSize, string destinationTableName = null, int? bulkCopyTimeout = null, SqlTransaction externalTransaction = null);
}
SqlBulkCopy简单封装,让批量插入更方便

上面都有详细解释,相信大家一看就会明白,接下来演示下用法及效果:

先创建一个测试的 Users 表:

SqlBulkCopy简单封装,让批量插入更方便
  1 CREATE TABLE [dbo].[Users](
  2 [Id] [uniqueidentifier] NOT NULL,
  3 [Name] [nvarchar](100) NULL,
  4 [Gender] [int] NULL,
  5 [Age] [int] NULL,
  6 [CityId] [int] NULL,
  7 [OpTime] [datetime] NULL,
  8  CONSTRAINT [PK_Users] PRIMARY KEY CLUSTERED
  9 (
 10 [Id] ASC
 11 )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
 12 ) ON [PRIMARY]
SqlBulkCopy简单封装,让批量插入更方便

然后定义一个与表映射的 Model,记住,由于 SqlBulkCopy 的特性,定义的 Model 必须拥有与表所有的字段对应的属性:

SqlBulkCopy简单封装,让批量插入更方便
  1 public enum Gender
  2 {
  3     Man = 1,
  4     Woman
  5 }
  6 
  7 public class User
  8 {
  9     public Guid Id { get; set; }
 10     public string Name { get; set; }
 11     public Gender? Gender { get; set; }
 12     public int? Age { get; set; }
 13     public int? CityId { get; set; }
 14     public DateTime? OpTime { get; set; }
 15 }
SqlBulkCopy简单封装,让批量插入更方便


制造些数据,然后就可以直接插入了:

SqlBulkCopy简单封装,让批量插入更方便
  1 List<User> usersToInsert = new List<User>();
  2 usersToInsert.Add(new User() { Id = Guid.NewGuid(), Name = "so1", Gender = Gender.Man, Age = 18, CityId = 1, OpTime = DateTime.Now });
  3 usersToInsert.Add(new User() { Id = Guid.NewGuid(), Name = "so2", Gender = Gender.Man, Age = 19, CityId = 2, OpTime = DateTime.Now });
  4 usersToInsert.Add(new User() { Id = Guid.NewGuid(), Name = "so3", Gender = Gender.Man, Age = 20, CityId = 3, OpTime = DateTime.Now });
  5 usersToInsert.Add(new User() { Id = Guid.NewGuid(), Name = "so4", Gender = Gender.Man, Age = 21, CityId = 4, OpTime = DateTime.Now });
  6 
  7 using (SqlConnection conn = new SqlConnection("Data Source = .;Initial Catalog = Chloe;Integrated Security = SSPI;"))
  8 {
  9     conn.BulkCopy(usersToInsert, 20000, "Users");
 10 }
SqlBulkCopy简单封装,让批量插入更方便

执行插入后表数据:

SqlBulkCopy简单封装,让批量插入更方便

很方便吧,定义好 Model,调用 BulkCopy 方法就能插入了。这个方法主要解决了两个问题:1.免去手动构造 DataTable 和向 DataTable 填充数据,要知道,SqlBulkCopy 要求 DataTable 的列必须和表列顺序一致,如果手动构造 DataTable 的话会使代码很难维护;2.不用亲自 new 出 SqlBulkCopy 对象以及手动给 SqlBulkCopy 对象设置各种值,如 DestinationTableName、BulkCopyTimeout、BatchSize 等,用封装的方法,直接传相应的值就好了。接下来贴干货,简单介绍下实现。

先了解 SqlBulkCopy 的定义(部分):

SqlBulkCopy简单封装,让批量插入更方便
public sealed class SqlBulkCopy : IDisposable
{
    public SqlBulkCopy(SqlConnection connection);
    public SqlBulkCopy(string connectionString);
    public SqlBulkCopy(string connectionString, SqlBulkCopyOptions copyOptions);
    public SqlBulkCopy(SqlConnection connection, SqlBulkCopyOptions copyOptions, SqlTransaction externalTransaction);

    public int BatchSize { get; set; }
    public int BulkCopyTimeout { get; set; }
    public SqlBulkCopyColumnMappingCollection ColumnMappings { get; }
    public string DestinationTableName { get; set; }
    public bool EnableStreaming { get; set; }
    public int NotifyAfter { get; set; }
    public event SqlRowsCopiedEventHandler SqlRowsCopied;

    public void Close();
    public void WriteToServer(DataRow[] rows);
    public void WriteToServer(DataTable table);
    public void WriteToServer(IDataReader reader);
    public void WriteToServer(DataTable table, DataRowState rowState);
}
SqlBulkCopy简单封装,让批量插入更方便

我们只需关注 WriteToServer 方法。因为我们的数据源不是数据库或excel,所以我们直接不考虑 WriteToServer(IDataReader reader)。WriteToServer(DataRow[] rows) 直接无视,不多解释,所以我们只需考虑用 WriteToServer(DataTable table) 就行了。开干!

一、构造一个结构严谨的 DataTable。
由于 SqlBulkCopy 要求 DataTable 的列必须和表列顺序一致,并且不能多也不能少,所以,我们首先要创建一个和目标表字段顺序一致的 DataTable,先查出目标表的结构:

SqlBulkCopy简单封装,让批量插入更方便
static List<SysColumn> GetTableColumns(SqlConnection sourceConn, string tableName)
{
    string sql = string.Format("select * from syscolumns inner join sysobjects on syscolumns.id=sysobjects.id where sysobjects.xtype=‘U‘ and sysobjects.name=‘{0}‘ order by syscolumns.colid asc", tableName);

    List<SysColumn> columns = new List<SysColumn>();
    using (SqlConnection conn = (SqlConnection)((ICloneable)sourceConn).Clone())
    {
        conn.Open();
        using (var reader = conn.ExecuteReader(sql))
        {
            while (reader.Read())
            {
                SysColumn column = new SysColumn();
                column.Name = reader.GetDbValue("name");
                column.ColOrder = reader.GetDbValue("colorder");

                columns.Add(column);
            }
        }
        conn.Close();
    }

    return columns;
}
SqlBulkCopy简单封装,让批量插入更方便

得到基本的表结构 List<SysColumn>,再创建“严格”的 DataTable 对象:

SqlBulkCopy简单封装,让批量插入更方便
DataTable dt = new DataTable();

Type modelType = typeof(TModel);

List<SysColumn> columns = GetTableColumns(conn, tableName);
List<PropertyInfo> mappingProps = new List<PropertyInfo>();

var props = modelType.GetProperties();
for (int i = 0; i < columns.Count; i  )
{
    var column = columns[i];
    PropertyInfo mappingProp = props.Where(a => a.Name == column.Name).FirstOrDefault();
    if (mappingProp == null)
        throw new Exception(string.Format("model 类型 ‘{0}‘未定义与表 ‘{1}‘ 列名为 ‘{2}‘ 映射的属性", modelType.FullName, tableName, column.Name));

    mappingProps.Add(mappingProp);
    Type dataType = GetUnderlyingType(mappingProp.PropertyType);
    if (dataType.IsEnum)
        dataType = typeof(int);
    dt.Columns.Add(new DataColumn(column.Name, dataType));
}
SqlBulkCopy简单封装,让批量插入更方便

注意,构造 DataColumn 时,要给 Column 设置 DataType,及数据类型。因为如果不指定数据类型,默认是 string 类型,那样会导致将数据发送至数据库时会引起数据转换,会有些许无谓的性能损耗,同时,如果不指定数据类型,导入一些数据类型时可能会失败,比如模型属性是 Guid 类型,导入时会出现类型转换失败异常。

二、利用反射,获取属性值,构造一行一行的 DataRow,填充 DataTable:

SqlBulkCopy简单封装,让批量插入更方便
foreach (var model in modelList)
{
    DataRow dr = dt.NewRow();
    for (int i = 0; i < mappingProps.Count; i  )
    {
        PropertyInfo prop = mappingProps[i];
        object value = prop.GetValue(model);

        if (GetUnderlyingType(prop.PropertyType).IsEnum)
        {
            if (value != null)
                value = (int)value;
        }

        dr[i] = value ?? DBNull.Value;
    }

    dt.Rows.Add(dr);
}
SqlBulkCopy简单封装,让批量插入更方便

三、一个完整包含数据的 DataTable 对象就创建好了,我们就可以使用 SqlBulkCopy 插入数据了:

SqlBulkCopy简单封装,让批量插入更方便
public static void BulkCopy<TModel>(this SqlConnection conn, List<TModel> modelList, int batchSize, string destinationTableName = null, int? bulkCopyTimeout = null, SqlTransaction externalTransaction = null)
{
    bool shouldCloseConnection = false;

    if (string.IsNullOrEmpty(destinationTableName))
        destinationTableName = typeof(TModel).Name;

    DataTable dtToWrite = ToSqlBulkCopyDataTable(modelList, conn, destinationTableName);

    SqlBulkCopy sbc = null;

    try
    {
        if (externalTransaction != null)
            sbc = new SqlBulkCopy(conn, SqlBulkCopyOptions.Default, externalTransaction);
        else
            sbc = new SqlBulkCopy(conn);

        using (sbc)
        {
            sbc.BatchSize = batchSize;
            sbc.DestinationTableName = destinationTableName;

            if (bulkCopyTimeout != null)
                sbc.BulkCopyTimeout = bulkCopyTimeout.Value;

            if (conn.State != ConnectionState.Open)
            {
                shouldCloseConnection = true;
                conn.Open();
            }

            sbc.WriteToServer(dtToWrite);
        }
    }
    finally
    {
        if (shouldCloseConnection && conn.State == ConnectionState.Open)
            conn.Close();
    }
}
SqlBulkCopy简单封装,让批量插入更方便

完事,一个批量插入的 Helper 方法就这么产生了,最终的完整实现如下:

SqlBulkCopy简单封装,让批量插入更方便SqlBulkCopy简单封装,让批量插入更方便
  1 public static class SqlConnectionExtension
  2 {
  3     /// <summary>
  4     /// 使用 SqlBulkCopy 向 destinationTableName 表插入数据
  5     /// </summary>
  6     /// <typeparam name="TModel">必须拥有与目标表所有字段对应属性</typeparam>
  7     /// <param name="conn"></param>
  8     /// <param name="modelList">要插入的数据</param>
  9     /// <param name="batchSize">SqlBulkCopy.BatchSize</param>
 10     /// <param name="destinationTableName">如果为 null,则使用 TModel 名称作为 destinationTableName</param>
 11     /// <param name="bulkCopyTimeout">SqlBulkCopy.BulkCopyTimeout</param>
 12     /// <param name="externalTransaction">要使用的事务</param>
 13     public static void BulkCopy<TModel>(this SqlConnection conn, List<TModel> modelList, int batchSize, string destinationTableName = null, int? bulkCopyTimeout = null, SqlTransaction externalTransaction = null)
 14     {
 15         bool shouldCloseConnection = false;
 16 
 17         if (string.IsNullOrEmpty(destinationTableName))
 18             destinationTableName = typeof(TModel).Name;
 19 
 20         DataTable dtToWrite = ToSqlBulkCopyDataTable(modelList, conn, destinationTableName);
 21 
 22         SqlBulkCopy sbc = null;
 23 
 24         try
 25         {
 26             if (externalTransaction != null)
 27                 sbc = new SqlBulkCopy(conn, SqlBulkCopyOptions.Default, externalTransaction);
 28             else
 29                 sbc = new SqlBulkCopy(conn);
 30 
 31             using (sbc)
 32             {
 33                 sbc.BatchSize = batchSize;
 34                 sbc.DestinationTableName = destinationTableName;
 35 
 36                 if (bulkCopyTimeout != null)
 37                     sbc.BulkCopyTimeout = bulkCopyTimeout.Value;
 38 
 39                 if (conn.State != ConnectionState.Open)
 40                 {
 41                     shouldCloseConnection = true;
 42                     conn.Open();
 43                 }
 44 
 45                 sbc.WriteToServer(dtToWrite);
 46             }
 47         }
 48         finally
 49         {
 50             if (shouldCloseConnection && conn.State == ConnectionState.Open)
 51                 conn.Close();
 52         }
 53     }
 54 
 55     public static DataTable ToSqlBulkCopyDataTable<TModel>(List<TModel> modelList, SqlConnection conn, string tableName)
 56     {
 57         DataTable dt = new DataTable();
 58 
 59         Type modelType = typeof(TModel);
 60 
 61         List<SysColumn> columns = GetTableColumns(conn, tableName);
 62         List<PropertyInfo> mappingProps = new List<PropertyInfo>();
 63 
 64         var props = modelType.GetProperties();
 65         for (int i = 0; i < columns.Count; i  )
 66         {
 67             var column = columns[i];
 68             PropertyInfo mappingProp = props.Where(a => a.Name == column.Name).FirstOrDefault();
 69             if (mappingProp == null)
 70                 throw new Exception(string.Format("model 类型 ‘{0}‘未定义与表 ‘{1}‘ 列名为 ‘{2}‘ 映射的属性", modelType.FullName, tableName, column.Name));
 71 
 72             mappingProps.Add(mappingProp);
 73             Type dataType = GetUnderlyingType(mappingProp.PropertyType);
 74             if (dataType.IsEnum)
 75                 dataType = typeof(int);
 76             dt.Columns.Add(new DataColumn(column.Name, dataType));
 77         }
 78 
 79         foreach (var model in modelList)
 80         {
 81             DataRow dr = dt.NewRow();
 82             for (int i = 0; i < mappingProps.Count; i  )
 83             {
 84                 PropertyInfo prop = mappingProps[i];
 85                 object value = prop.GetValue(model);
 86 
 87                 if (GetUnderlyingType(prop.PropertyType).IsEnum)
 88                 {
 89                     if (value != null)
 90                         value = (int)value;
 91                 }
 92 
 93                 dr[i] = value ?? DBNull.Value;
 94             }
 95 
 96             dt.Rows.Add(dr);
 97         }
 98 
 99         return dt;
100     }
101     static List<SysColumn> GetTableColumns(SqlConnection sourceConn, string tableName)
102     {
103         string sql = string.Format("select * from syscolumns inner join sysobjects on syscolumns.id=sysobjects.id where sysobjects.xtype=‘U‘ and sysobjects.name=‘{0}‘ order by syscolumns.colid asc", tableName);
104 
105         List<SysColumn> columns = new List<SysColumn>();
106         using (SqlConnection conn = (SqlConnection)((ICloneable)sourceConn).Clone())
107         {
108             conn.Open();
109             using (var reader = conn.ExecuteReader(sql))
110             {
111                 while (reader.Read())
112                 {
113                     SysColumn column = new SysColumn();
114                     column.Name = reader.GetDbValue("name");
115                     column.ColOrder = reader.GetDbValue("colorder");
116 
117                     columns.Add(column);
118                 }
119             }
120             conn.Close();
121         }
122 
123         return columns;
124     }
125 
126     static Type GetUnderlyingType(Type type)
127     {
128         Type unType = Nullable.GetUnderlyingType(type); ;
129         if (unType == null)
130             unType = type;
131 
132         return unType;
133     }
134 
135     class SysColumn
136     {
137         public string Name { get; set; }
138         public int ColOrder { get; set; }
139     }
140 }
141 
SqlBulkCopy简单封装,让批量插入更方便

代码不多,仅仅150行,大家可以直接拷走拿去用。其中用了反射,估计吃瓜群众可能不淡定了~哈哈,如果你真有大数据插入需求,这点反射消耗相对大数据插入简直九牛一毛,微乎其微,放心好了。

转自:https://www.cnblogs.com/so9527/p/6193154.html