.NET Dapper mysql 批量新增修改
dapper是C#程序员比较喜欢用的轻量级ORM，简单易学，只是没有批量新增以及修改（收费版有），写了如下扩展 /// <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);
}
}
使用方法：<br>新增： 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 },
});
修改：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");
来源:https://www.cnblogs.com/runningprogrammer/archive/2023/08/28/dapper-mysql.html
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