.NET Dapper mysql 批量新增修改

    /// <summary>
    /// dapper MySQL批量新增修改扩展
    /// </summary>
    public static class DapperExtensions
    {
        /// <summary>
        /// 批量插入
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="connection"></param>
        /// <param name="tableName">表名</param>
        /// <param name="items">数据列表</param>
        /// <param name="dataFunc"></param>
        /// <param name="duplicateData">主键相同修改字段</param>
        /// <param name="dbTransaction">事务</param>
        /// <param name="insert">insert,replace,insert ignore</param>
        /// <returns></returns>
        public static async Task BulkInsert<T>(
            this IDbConnection connection,
            string tableName,
            IReadOnlyCollection<T> items,
            Dictionary<string, Func<T, object>> dataFunc, IEnumerable<string>? duplicateData = null, IDbTransaction? dbTransaction = null, string insert = "INSERT")
        {
            const int MaxBatchSize = 5000;
            const int MaxParameterSize = 10000;

            var batchSize = Math.Min((int)Math.Ceiling((double)MaxParameterSize / dataFunc.Keys.Count), MaxBatchSize);
            var numberOfBatches = (int)Math.Ceiling((double)items.Count / batchSize);
            var columnNames = dataFunc.Keys;
            var insertSql = $"{insert} INTO {tableName} ({string.Join(",", columnNames.Select(e => $"`{e}`"))}) VALUES";
            var sqlToExecute = new List<Tuple<string, DynamicParameters>>();

            for (var i = 0; i < numberOfBatches; i++)
            {
                var dataToInsert = items.Skip(i * batchSize)
                    .Take(batchSize);
                var valueSql = GetQueries(dataToInsert, dataFunc);

                sqlToExecute.Add(Tuple.Create($"{insertSql}{string.Join(",", valueSql.Item1)}", valueSql.Item2));
            }

            var duplicate = string.Empty;
            if (duplicateData != null)
            {
                duplicate = $" ON DUPLICATE KEY UPDATE {string.Join(',', duplicateData.Select(d => $"`{d}`=VALUES(`{d}`)"))}";
            }

            foreach (var sql in sqlToExecute)
            {
                await connection.ExecuteAsync(sql.Item1 + duplicate, sql.Item2, commandTimeout: int.MaxValue, transaction: dbTransaction);
            }
        }

        private static Tuple<IEnumerable<string>, DynamicParameters> GetQueries<T>(
            IEnumerable<T> dataToInsert,
            Dictionary<string, Func<T, object>> dataFunc)
        {
            var parameters = new DynamicParameters();

            return Tuple.Create(
                dataToInsert.Select(e => $"({string.Join(",", GenerateQueryAndParameters(e, parameters, dataFunc))})"),
                parameters);
        }

        private static IEnumerable<string> GenerateQueryAndParameters<T>(
            T entity,
            DynamicParameters parameters,
            Dictionary<string, Func<T, object>> dataFunc)
        {
            var paramTemplateFunc = new Func<Guid, string>(guid => $"@p{guid:N}");
            var paramList = new List<string>();

            foreach (var key in dataFunc)
            {
                var paramName = paramTemplateFunc(Guid.NewGuid());
                parameters.Add(paramName, key.Value(entity));
                paramList.Add(paramName);
            }

            return paramList;
        }

        /// <summary>
        /// 批量更新
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="connection"></param>
        /// <param name="tableName">表名</param>
        /// <param name="items">数据列表</param>
        /// <param name="dataFunc"></param>
        /// <param name="primaryFunc"></param>
        /// <param name="primaryKey">主键字段</param>
        /// <param name="isIntKey">主键是否是数字类型</param>
        /// <param name="dbTransaction">事务</param>
        /// <returns></returns>
        public static async Task BulkUpdate<T>(
            this IDbConnection connection,
            string tableName,
            IReadOnlyCollection<T> items,
            Dictionary<string, Func<T, object>> dataFunc, Func<T, object> primaryFunc, string primaryKey, bool isIntKey = true, IDbTransaction? dbTransaction = null)
        {
            const int MaxBatchSize = 5000;
            const int MaxParameterSize = 10000;

            var batchSize = Math.Min((int)Math.Ceiling((double)MaxParameterSize / dataFunc.Keys.Count), MaxBatchSize);
            var numberOfBatches = (int)Math.Ceiling((double)items.Count / batchSize);
            var columnNames = dataFunc.Keys;
            var updateSql = $"UPDATE {tableName} SET";
            var sqlToExecute = new List<Tuple<string, DynamicParameters>>();

            for (var i = 0; i < numberOfBatches; i++)
            {
                var dataToUpdate = items.Skip(i * batchSize)
                    .Take(batchSize);
                var valueSql = GetUpdateQueries(dataToUpdate, dataFunc, primaryFunc, primaryKey, isIntKey);

                sqlToExecute.Add(Tuple.Create($"{updateSql}{valueSql.Item1}", valueSql.Item2));
            }


            foreach (var sql in sqlToExecute)
            {
                await connection.ExecuteAsync(sql.Item1, sql.Item2, commandTimeout: int.MaxValue, transaction: dbTransaction);
            }
        }
        private static Tuple<string, DynamicParameters> GetUpdateQueries<T>(
            IEnumerable<T> dataToUpdate,
            Dictionary<string, Func<T, object>> dataFunc, Func<T, object> primaryFunc, string primaryKey, bool isIntKey)
        {
            var paramTemplateFunc = new Func<Guid, T, (string param, string sql)>((guid, entity) =>
            {
                var keyValue = primaryFunc(entity);
                if (!isIntKey)
                {
                    keyValue = $"'{keyValue}'";
                }
                var param = $"@p{guid:N}";
                var sql = $"WHEN {keyValue} THEN {param}";

                return (param, sql);
            }
            );
            var parameters = new DynamicParameters();
            List<string> sqlList = new();
            foreach (var key in dataFunc)
            {
                var paramList = new List<string>();
                foreach (var e in dataToUpdate)
                {
                    var (param, sql) = paramTemplateFunc(Guid.NewGuid(), e);
                    parameters.Add(param, key.Value(e));
                    paramList.Add(sql);
                }
                sqlList.Add($"`{key.Key}`=CASE `{primaryKey}` {string.Join(" ", paramList)} END");
            }
            object idFunc(T p)
            {
                return primaryFunc(p);
            }
            parameters.Add("@ids", dataToUpdate.Select(idFunc));
            return Tuple.Create(
                $"{string.Join(",", sqlList)} WHERE `{primaryKey}` IN @ids",
                parameters);
        }
    }

 await conn.BulkInsert(
                    "userInfo",    //表名    
                     userinfoList,    //列表
                     new Dictionary<string, Func<UserInfo, object>>
                         {
                             {"Name", u => u.Name },
                             {"Age", u => u.Age },
                             {"Sex", u => u.Sex },
                         });

await conn.BulkUpdate("userInfo", userInfoList, new Dictionary<string, Func<UserInfo, object>>
                        {
                         　　{"Name", u => u.Name }
                             {"Age", u => u.Age },
                             {"Sex", u => u.Sex },
                        　　}, new Func<UserInfo, object>(u => u.ID), "ID");