SharpJuice.ClickHouse 1.0.7

Writing .Net objects to ClickHouse

Octonica.ClickHouseClient extension for easily writing objects to ClickHouse using bulk insert and ArrayPool for high performance and low memory allocation.

Registration

    ClickHouseConnectionSettings connectionSettings = ...;

    services.AddSingleton<IClickHouseConnectionFactory>(new ClickHouseConnectionFactory(connectionSettings));
    services.AddSingleton<ITableWriterBuilder, TableWriterBuilder>();	
    services.AddSingleton<ClickHouseRepository>();	

Flat object

    public sealed class ClickHouseRepository 
    {
        private readonly ITableWriter<Order> _tableWriter;
        
        public ClickHouseRepository(ITableWriterBuilder tableWriterBuilder)
        {
            _tableWriter = tableWriterBuilder
                .For<Order>("table_name")
                .AddColumn("order_id", a => a.OrderId)
                .AddColumn("user_id", a => a.UserId)
                .AddColumn("created_at", a => a.CreatedAt)                
		.Build();
        }

        public async Task Add(IReadOnlyCollection<Order> orders, CancellationToken token)
        {
	    ...
            await _tableWriter.Insert(orders, token);
	    ...
        }
    }

Nested objects

    public sealed class ClickHouseRepository 
    {
        private readonly ITableWriter<Order> _tableWriter;
        
        public ClickHouseRepository(ITableWriterBuilder tableWriterBuilder)
        {
            _tableWriter = tableWriterBuilder
                .For<Order>("table_name")
                .AddColumn("order_id", a => a.OrderId)
                .AddColumn("date", a => a.Date)
                .AddNestedColumn("item", x => x.Items, c => c
                    .AddColumn("id", x => x.Id)
                    .AddColumn("quantity", x => x.Quantity)
                    .AddColumn("name", x => x.Name)
                    .AddColumn("price", x => x.Price))
                .AddNestedColumn(x => x.Discounts, c => c
                    .AddColumn("discount.id", x => x.Id)
                    .AddColumn("discount.name", x => x.Name)
                    .AddColumn("discount.value", x => x.Value))                
                .Build();          
        }

        public async Task Add(IReadOnlyCollection<Order> orders, CancellationToken token)
        {
	    ...
            await _tableWriter.Insert(orders, token);
	    ...
        }
    }

Array join (only one ArrayJoin per writer)

    public sealed class ClickHouseRepository 
    {
        private readonly ITableWriter<Order> _tableWriter;
        
        public ClickHouseRepository(ITableWriterBuilder tableWriterBuilder)
        {
            _tableWriter = tableWriterBuilder
                .For<Order>("table_name")
                .AddColumn("order_id", a => a.OrderId)
                .AddColumn("date", a => a.Date)
                .ArrayJoin(a => a.Items, c => c
                    .AddColumn("item_id", x => x.Id)
                    .AddColumn("item_quantity", x => x.Quantity)
                    .AddColumn("item_name", x => x.Name)
                    .AddColumn("item_price", x => x.Price))
		    .Build();
        }

        public async Task Add(IReadOnlyCollection<Order> orders, CancellationToken token)
        {
	    ...
            await _tableWriter.Insert(orders, token);
	    ...
        }
    }

Performance and memory allocation benchmark (.net 8)

Benchmark source code

Thanks to @deniskuzmin and @LegaNoga