使用MySqlBulkLoader批量插入数据

最近在项目中遇到插入几万、几十万、几百万的数据到MYSQL数据库，使用EF插入会发现插入速度非常慢的场景，

数据量非常大时EF插入需要几十分钟，甚至几个小时，这样子的速度肯定不是我们所期望的。

后面经过了解与研究发现MySqlBulkLoader，可以批量将数据插入到数据库并且速度上面远远优于EF。

MySqlBulkLoader主要的实现方式：将需要插入的数据转成DataTable，转成一个CSV文件，将CSV文件使用批量导入的形式导入到数据库里面去。

注意：

1.数据库连接地址需要添加配置AllowLoadLocalInfile=true,允许本地文件导入；

Data Source = 数据库地址; Port = 端口; Initial Catalog = 数据库名; User Id = 用户名; Password = 密码;AllowLoadLocalInfile=true;

2.插入的时候会返回插入行数，但是检查所有的数据都正确，也没有报异常，却返回了插入数量为0，可以检查表是否有唯一索引，插入的数据是否违反了唯一索引。

（以下分块展示了代码，如果需要看完整的代码直接看 5.完整的代码）

1.将List转化为DataTable

   /// <summary>
        /// 将List转化为DataTable
        /// </summary>
        /// <returns></returns>
        public DataTable ListToDataTable<T>(List<T> data)
        {
            #region 创建一个DataTable，以实体名称作为DataTable名称

            var tableName = typeof(T).Name;
            tableName = tableName.ToSnakeCase(); /*实体名称与表名进行转化，主要根据各项目的规定进行转化,不一定就是我这些写的这种转换方式*/
            DataTable dt = new DataTable
            {
                TableName = tableName
            };

            #endregion

            #region 拿取列名，以实体的属性名作为列名       

            var properties = typeof(T).GetProperties();
            foreach (var item in properties)
            {
                var curFileName = item.Name;
                curFileName = curFileName.ToSnakeCase();/*列名与表名进行转化，主要根据各项目的规定进行转化,不一定就是我这些写的这种转换方式*/
                dt.Columns.Add(curFileName);
            }

            #endregion

            #region 列赋值
            foreach (var item in data)
            {
                DataRow dr = dt.NewRow();
                var columns = dt.Columns;

                var curPropertyList = item.GetType().GetProperties();
                foreach (var p in curPropertyList)
                {
                    var name = p.Name;
                    name = name.ToSnakeCase();/*列名与表名进行转化，主要根据各项目的规定进行转化,不一定就是我这些写的这种转换方式*/
                    var curValue = p.GetValue(item);

                    int i = columns.IndexOf(name);
                    dr[i] = curValue;
                }

                dt.Rows.Add(dr);
            }

            #endregion  

            return dt;
        }

2.将DataTable转换为标准的CSV文件

  /// <summary>
    /// csv扩展
    /// </summary>
    public static class CSVEx
    {
        /// <summary>
        ///将DataTable转换为标准的CSV文件
        /// </summary>
        /// <param name="table">数据表</param>
        /// <param name="tmpPath">文件地址</param>
        /// <returns>返回标准的CSV</returns>
        public static void ToCsv(this DataTable table, string tmpPath)
        {
            //以半角逗号（即,）作分隔符，列为空也要表达其存在。
            //列内容如存在半角逗号（即,）则用半角引号（即""）将该字段值包含起来。
            //列内容如存在半角引号（即"）则应替换成半角双引号（""）转义，并用半角引号（即""）将该字段值包含起来。
            StringBuilder sb = new StringBuilder();
            DataColumn colum;
            foreach (DataRow row in table.Rows)
            {
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    Type _datatype = typeof(DateTime);
                    colum = table.Columns[i];
                    if (i != 0) sb.Append("\t");
                    //if (colum.DataType == typeof(string) && row[colum].ToString().Contains(","))
                    //{
                    //    sb.Append("\"" + row[colum].ToString().Replace("\"", "\"\"") + "\"");
                    //}
                    if (colum.DataType == _datatype)
                    {
                        sb.Append(((DateTime)row[colum]).ToString("yyyy/MM/dd HH:mm:ss"));
                    }
                    else sb.Append(row[colum].ToString());
                }
                sb.Append("\r\n");
            }
            StreamWriter sw = new StreamWriter(tmpPath, false, UTF8Encoding.UTF8);
            sw.Write(sb.ToString());
            sw.Close();
        }

    }

3.CSV文件导入数据到数据库

    /// <summary>
    /// 批量导入mysql帮助类
    /// </summary>
    public static class MySqlHelper
    {
        /// <summary>
        /// MySqlBulkLoader批量导入
        /// </summary>
        /// <param name="_mySqlConnection">数据库连接地址</param>
        /// <param name="table"></param>
        /// <param name="csvName"></param>
        /// <returns></returns>
        public static int BulkLoad(MySqlConnection _mySqlConnection, DataTable table, string csvName)
        {
            var columns = table.Columns.Cast<DataColumn>().Select(colum => colum.ColumnName).ToList();
            MySqlBulkLoader bulk = new MySqlBulkLoader(_mySqlConnection)
            {
                FieldTerminator = "\t",
                FieldQuotationCharacter = '"',
                EscapeCharacter = '"',
                LineTerminator = "\r\n",
                FileName = csvName,
                NumberOfLinesToSkip = 0,
                TableName = table.TableName,

            };

            bulk.Columns.AddRange(columns);
            return bulk.Load();
        }
    }

4.使用MySqlBulkLoader批量插入数据

        /// <summary>
        /// 使用MySqlBulkLoader批量插入数据
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="data"></param>
        /// <returns></returns>
        /// <exception cref="Exception"></exception>
        public int BulkLoaderData<T>(List<T> data)
        {
            if (data.Count <= 0) return 0;

            var connectString = "数据库连接地址";
            using (MySqlConnection connection = new MySqlConnection(connectString))
            {
                MySqlTransaction sqlTransaction = null;
                try
                {
                    if (connection.State == ConnectionState.Closed)
                    {
                        connection.Open();
                    }
                    sqlTransaction = connection.BeginTransaction();

                    var dt = ListToDataTable<T>(data); //将List转成dataTable
                    string tmpPath = Path.GetTempFileName();
                    dt.ToCsv(tmpPath); //将DataTable转成CSV文件
                    var insertCount = MySqlHelper.BulkLoad(connection, dt, tmpPath); //使用MySqlBulkLoader插入数据
                    sqlTransaction.Commit();

                    try
                    {
                        if (File.Exists(tmpPath)) File.Delete(tmpPath);
                    }
                    catch (Exception)
                    {
                        //删除文件失败

                    }
                    return insertCount; //返回执行成功的条数
                }
                catch (Exception e)
                {
                    if (sqlTransaction != null)
                    {
                        sqlTransaction.Rollback();
                    }
                    //执行异常
                    throw e;
                }
            }

        }

5.完整的代码：

namespace WebApplication1.BrantchInsert
{

    /// <summary>
    /// 批量插入
    /// </summary>
    public class BulkLoader
    {

        /// <summary>
        /// 测试批量插入入口
        /// </summary>
        /// <returns></returns>
        public int BrantchDataTest()
        {

            #region 模拟数据
            var data = new List<CrmCouponTestDto>() {
                 new CrmCouponTestDto {
                     Id=1,
                     CouponCode="test001",
                     CouponId = 1,
                     MemberId=100,
                     IssueTime=Convert.ToDateTime("2022-06-27 14:00:00"),
                     UsageTime=Convert.ToDateTime("3000-12-31 00:00:00"),
                     UsageShopId=0,
                     UsageBillNo="",
                     EffectiveStart=Convert.ToDateTime("2022-06-27 14:00:00"),
                     EffectiveEnd=Convert.ToDateTime("2023-06-27 14:00:00"),
                     Status=0
                 },
                 new CrmCouponTestDto {
                     Id=2,
                     CouponCode="test002",
                     CouponId = 1,
                       MemberId=101,
                     IssueTime=Convert.ToDateTime("2022-06-27 14:00:00"),
                     UsageTime=Convert.ToDateTime("2022-06-27 14:30:00"),
                     UsageShopId=2,
                     UsageBillNo="CS202206271430001",
                     EffectiveStart=Convert.ToDateTime("2022-06-27 14:00:00"),
                     EffectiveEnd=Convert.ToDateTime("2023-06-27 14:00:00"),
                     Status=1
                 },
                  new CrmCouponTestDto {
                     Id=3,
                     CouponCode="test003",
                     CouponId = 1,
                     MemberId=102,
                     IssueTime=Convert.ToDateTime("2022-06-27 14:00:00"),
                     UsageTime=Convert.ToDateTime("3000-12-31 00:00:00"),
                     UsageShopId=0,
                     UsageBillNo="",
                     EffectiveStart=Convert.ToDateTime("2022-06-27 14:00:00"),
                     EffectiveEnd=Convert.ToDateTime("2023-06-27 14:00:00"),
                     Status=0
                 },
                    new CrmCouponTestDto {
                     Id=4,
                     CouponCode="test004",
                     CouponId = 1,
                     MemberId=103,
                     IssueTime=Convert.ToDateTime("2022-06-27 14:00:00"),
                     UsageTime=Convert.ToDateTime("3000-12-31 00:00:00"),
                     UsageShopId=0,
                     UsageBillNo="",
                     EffectiveStart=Convert.ToDateTime("2022-06-27 14:00:00"),
                     EffectiveEnd=Convert.ToDateTime("2023-06-27 14:00:00"),
                     Status=0
                 }
             };
            #endregion
            var result = BulkLoaderData<CrmCouponTestDto>(data);
            return result;

        }

        /// <summary>
        /// 使用MySqlBulkLoader批量插入数据
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="data"></param>
        /// <returns></returns>
        /// <exception cref="Exception"></exception>
        public int BulkLoaderData<T>(List<T> data)
        {
            if (data.Count <= 0) return 0;

            var connectString = "数据库连接地址";
            using (MySqlConnection connection = new MySqlConnection(connectString))
            {
                MySqlTransaction sqlTransaction = null;
                try
                {
                    if (connection.State == ConnectionState.Closed)
                    {
                        connection.Open();
                    }
                    sqlTransaction = connection.BeginTransaction();

                    var dt = ListToDataTable<T>(data); //将List转成dataTable
                    string tmpPath = Path.GetTempFileName();
                    dt.ToCsv(tmpPath); //将DataTable转成CSV文件
                    var insertCount = MySqlHelper.BulkLoad(connection, dt, tmpPath); //使用MySqlBulkLoader插入数据
                    sqlTransaction.Commit();

                    try
                    {
                        if (File.Exists(tmpPath)) File.Delete(tmpPath);
                    }
                    catch (Exception)
                    {
                        //删除文件失败

                    }
                    return insertCount; //返回执行成功的条数
                }
                catch (Exception e)
                {
                    if (sqlTransaction != null)
                    {
                        sqlTransaction.Rollback();
                    }
                    //执行异常
                    throw e;
                }
            }

        }

        /// <summary>
        /// 将List转化为DataTable核心方法
        /// </summary>
        /// <returns></returns>
        public DataTable ListToDataTable<T>(List<T> data)
        {
            #region 创建一个DataTable，以实体名称作为DataTable名称

            var tableName = typeof(T).Name;
            tableName = tableName.ToSnakeCase(); /*实体名称与表名进行转化，主要根据各项目的规定进行转化,不一定就是我这些写的这种转换方式*/
            DataTable dt = new DataTable
            {
                TableName = tableName
            };

            #endregion

            #region 拿取列名，以实体的属性名作为列名       

            var properties = typeof(T).GetProperties();
            foreach (var item in properties)
            {
                var curFileName = item.Name;
                curFileName = curFileName.ToSnakeCase();/*列名与表名进行转化，主要根据各项目的规定进行转化,不一定就是我这些写的这种转换方式*/
                dt.Columns.Add(curFileName);
            }

            #endregion

            #region 列赋值
            foreach (var item in data)
            {
                DataRow dr = dt.NewRow();
                var columns = dt.Columns;

                var curPropertyList = item.GetType().GetProperties();
                foreach (var p in curPropertyList)
                {
                    var name = p.Name;
                    name = name.ToSnakeCase();/*列名与表名进行转化，主要根据各项目的规定进行转化,不一定就是我这些写的这种转换方式*/
                    var curValue = p.GetValue(item);

                    int i = columns.IndexOf(name);
                    dr[i] = curValue;
                }

                dt.Rows.Add(dr);
            }

            #endregion  

            return dt;
        }

    }

    /// <summary>
    /// 批量导入mysql帮助类
    /// </summary>
    public static class MySqlHelper
    {
        /// <summary>
        /// MySqlBulkLoader批量导入
        /// </summary>
        /// <param name="_mySqlConnection">数据库连接地址</param>
        /// <param name="table"></param>
        /// <param name="csvName"></param>
        /// <returns></returns>
        public static int BulkLoad(MySqlConnection _mySqlConnection, DataTable table, string csvName)
        {
            var columns = table.Columns.Cast<DataColumn>().Select(colum => colum.ColumnName).ToList();
            MySqlBulkLoader bulk = new MySqlBulkLoader(_mySqlConnection)
            {
                FieldTerminator = "\t",
                FieldQuotationCharacter = '"',
                EscapeCharacter = '"',
                LineTerminator = "\r\n",
                FileName = csvName,
                NumberOfLinesToSkip = 0,
                TableName = table.TableName,

            };

            bulk.Columns.AddRange(columns);
            return bulk.Load();
        }
    }

    /// <summary>
    /// csv扩展
    /// </summary>
    public static class CSVEx
    {
        /// <summary>
        ///将DataTable转换为标准的CSV文件
        /// </summary>
        /// <param name="table">数据表</param>
        /// <param name="tmpPath">文件地址</param>
        /// <returns>返回标准的CSV</returns>
        public static void ToCsv(this DataTable table, string tmpPath)
        {
            //以半角逗号（即,）作分隔符，列为空也要表达其存在。
            //列内容如存在半角逗号（即,）则用半角引号（即""）将该字段值包含起来。
            //列内容如存在半角引号（即"）则应替换成半角双引号（""）转义，并用半角引号（即""）将该字段值包含起来。
            StringBuilder sb = new StringBuilder();
            DataColumn colum;
            foreach (DataRow row in table.Rows)
            {
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    Type _datatype = typeof(DateTime);
                    colum = table.Columns[i];
                    if (i != 0) sb.Append("\t");
                    //if (colum.DataType == typeof(string) && row[colum].ToString().Contains(","))
                    //{
                    //    sb.Append("\"" + row[colum].ToString().Replace("\"", "\"\"") + "\"");
                    //}
                    if (colum.DataType == _datatype)
                    {
                        sb.Append(((DateTime)row[colum]).ToString("yyyy/MM/dd HH:mm:ss"));
                    }
                    else sb.Append(row[colum].ToString());
                }
                sb.Append("\r\n");
            }
            StreamWriter sw = new StreamWriter(tmpPath, false, UTF8Encoding.UTF8);
            sw.Write(sb.ToString());
            sw.Close();
        }

    }

    /// <summary>
    /// 字符串转化
    /// </summary>
    public static class StringExtensions
    {
        /// <summary>
        /// 转换为 main_keys_id 这种形式的字符串方式
        /// </summary>
        public static string ToSnakeCase(this string input)
        {
            if (string.IsNullOrEmpty(input)) { return input; }

            var startUnderscores = Regex.Match(input, @"^_+");
            return startUnderscores + Regex.Replace(input, @"([a-z0-9])([A-Z])", "$1_$2").ToLower();
        }
    }

    /// <summary>
    /// 实体
    /// </summary>
    public class CrmCouponTestDto
    {
        /// <summary>
        /// ID
        /// </summary>
        public long Id { get; set; }

        /// <summary>
        /// 卡券号
        /// </summary>
        public string CouponCode { get; set; }

        /// <summary>
        /// 卡券ID
        /// </summary>
        public int CouponId { get; set; }

        /// <summary>
        /// 会员ID
        /// </summary>
        public int MemberId { get; set; }

        /// <summary>
        /// 发放时间
        /// </summary>
        public DateTime IssueTime { get; set; }

        /// <summary>
        /// 使用时间
        /// </summary>
        public DateTime UsageTime { get; set; }

        /// <summary>
        /// 使用店铺ID
        /// </summary>      

        public int UsageShopId { get; set; }

        /// <summary>
        /// 使用单号
        /// </summary>
        public string UsageBillNo { get; set; }

        /// <summary>
        /// 有效开始时间
        /// </summary>
        public DateTime EffectiveStart { get; set; }

        /// <summary>
        /// 有效结束时间
        /// </summary>
        public DateTime EffectiveEnd { get; set; }

        /// <summary>
        /// 状态
        /// CouponStatus 卡券状态:
        /// -1：未领用
        /// 0：未使用
        /// 1：已使用
        /// 2：已过期
        ///3：已作废
        ///4：转赠中
        /// </summary>

        public Int16 Status { get; set; }
    }
}

完整代码