Dommel.Bulk 2.0.0-beta

This is a prerelease version of Dommel.Bulk.
dotnet add package Dommel.Bulk --version 2.0.0-beta
NuGet\Install-Package Dommel.Bulk -Version 2.0.0-beta
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="Dommel.Bulk" Version="2.0.0-beta" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add Dommel.Bulk --version 2.0.0-beta
#r "nuget: Dommel.Bulk, 2.0.0-beta"
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
// Install Dommel.Bulk as a Cake Addin
#addin nuget:?package=Dommel.Bulk&version=2.0.0-beta&prerelease

// Install Dommel.Bulk as a Cake Tool
#tool nuget:?package=Dommel.Bulk&version=2.0.0-beta&prerelease


High performance insert data into database

Dommel.Bulk provides a convenient API for bulk insert operations using extension methods on the IDbConnection interface. The SQL queries are generated based on your POCO entities. Dommel.Bulk translates you entities to SQL expressions. Dapper is used for query execution and object mapping. Dommel is used for table and column names conventions

Installing Dommel.Bulk

Dommel.Bulk is available on NuGet.

Install using the .NET CLI:

dotnet add package Dommel.Bulk

Install using the NuGet Package Manager:

Install-Package Dommel.Bulk

Dommel.Bulk basic usage

Bulk insert using type mappers

var products = await connection.BulkInsertAsync<Product>(products);

Generate simple SQL expression using database specific type mappers. Supports MySql database. Has high performance.

Bulk insert using SQL parameters

int insertedCount = await connection.BulkInsertParametersAsync<Product>(products);

Use SQL parameters for insert values. Support for all databases. Has middle performance.

Dommel.Bulk extended usage


All extension methods supports database transaction usage. Example:

using (IDbTransaction transaction = _connection.BeginTransaction())
    await _connection.BulkInsertAsync(data, transaction);


Dommel.Bulk supports flags that allow additional database functionality to control bulk insertion.

Flag Description
None Does not use extended functionality
InsertDatabaseGeneratedKeys Insert auto increment keys into database
UpdateIfExists Update rows in database when they exist. This flag is enabled if propertiesToUpdate exists
IgnoreErrors Ignore duplicate keys or unique index errors


await _connection.BulkInsertAsync(data, flags: ExecutionFlags.IgnoreErrors);

Properties to update

You can specify which properties to update if there are conflicts when inserting.

await _connection.BulkInsertAsync(data, null, default, null, flags: ExecutionFlags.IgnoreErrors, nameof(Person.FirstName), nameof(Person.LastName));

Type mappers

Mapping C# Types to Database Type Literals Support CLR types: bool, byte, char, double, float, int, long, sbyte, short, uint, ulong, ushort, decimal, DateTime, Guid, string, TimeSpan, byte[], enum types and nullable types.

Async and non-async

All Dommel.Bulk methods have async and non-async variants, such as as BulkInsert & BulkInsertAsync, BulkInsertParameters & BulkInsertParametersAsync.

Database adapters

Represents a concrete implementation of a database abstraction. Supports only MySql implementation


Type mapper

Use the AddTypeMapper() method to register the custom type mapper.

DommelBulkMapper.AddTypeMapper(typeof(MySqlConnection), new GenericTypeMapper<JsonElement>((e, tw) => tw.Write(e.ToString())));

Database adapter

Use the AddTypeMapper() method to register the custom type mapper.

DommelBulkMapper.AddDatabaseAdapter(typeof(NpgsqlConnection), new NpgDatabaseAdapter());


Performance comparison between bulk methods and InsertAll from Dommel library

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.19044.1586 (21H2)
Intel Core i5-7300HQ CPU 2.50GHz (Kaby Lake), 1 CPU, 4 logical and 4 physical cores
.NET SDK=6.0.100
  [Host]     : .NET 6.0.0 (, X64 RyuJIT
  DefaultJob : .NET 6.0.0 (, X64 RyuJIT

Method Categories DataSize Mean Error StdDev Ratio Gen 0 Gen 1 Gen 2 Allocated
BulkInsertBenchmarkAsync simple 10000 1,989.8 ms 86.79 ms 45.39 ms 1.00 13000.0000 5000.0000 1000.0000 273 MB
SqlBuilderBenchmark simple 10000 140.7 ms 22.24 ms 13.23 ms 0.07 13000.0000 5000.0000 1000.0000 143 MB
BulkInsertParametersBenchmarkAsync parameters 10000 3,029.4 ms 71.10 ms 42.31 ms 1.00 43000.0000 12000.0000 2000.0000 368 MB
SqlBuilderParametersBenchmark parameters 10000 516.9 ms 16.59 ms 10.98 ms 0.17 19000.0000 7000.0000 1000.0000 156 MB
InsertAllBenchmarkAsync 10000 107.21 s 29.986 s 19.834 s 38000.0000 3000.0000 - 114 MB
InsertAllTransactionBenchmarkAsync 10000 15.98 s 1.354 s 0.896 s 37000.0000 1000.0000 - 113 MB


The material embodied in this software is provided to you "as-is" and without warranty of any kind, express, implied or otherwise, including without limitation, any warranty of fitness for a particular purpose. In no event shall the Centers for Disease Control and Prevention (CDC) or the United States (U.S.) government be liable to you or anyone else for any direct, special, incidental, indirect or consequential damages of any kind, or any damages whatsoever, including without limitation, loss of profit, loss of use, savings or revenue, or the claims of third parties, whether or not CDC or the U.S. government has been advised of the possibility of such loss, however caused and on any theory of liability, arising out of or in connection with the possession, use or performance of this software.

Product Compatible and additional computed target framework versions.
.NET net5.0 was computed.  net5.0-windows was computed.  net6.0 is compatible.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed.  net8.0 was computed.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed. 
.NET Core netcoreapp2.0 was computed.  netcoreapp2.1 was computed.  netcoreapp2.2 was computed.  netcoreapp3.0 was computed.  netcoreapp3.1 was computed. 
.NET Standard netstandard2.0 is compatible.  netstandard2.1 was computed. 
.NET Framework net461 was computed.  net462 was computed.  net463 was computed.  net47 was computed.  net471 was computed.  net472 was computed.  net48 was computed.  net481 was computed. 
MonoAndroid monoandroid was computed. 
MonoMac monomac was computed. 
MonoTouch monotouch was computed. 
Tizen tizen40 was computed.  tizen60 was computed. 
Xamarin.iOS xamarinios was computed. 
Xamarin.Mac xamarinmac was computed. 
Xamarin.TVOS xamarintvos was computed. 
Xamarin.WatchOS xamarinwatchos was computed. 
Compatible target framework(s)
Additional computed target framework(s)
Learn more about Target Frameworks and .NET Standard.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
2.0.0-beta 216 5/6/2022
1.0.0 501 3/24/2022
1.0.0-beta 126 3/19/2022

Added support for extended behavior when inserting data into a database.
           Added limited support for PostgreSQL database