1. MooseStack
  3. Table Engines

Table Engines

ClickHouse table engines determine how data is stored, indexed, queried, and replicated.

MooseOLAP selects the engine in the OlapTable config:

You set the engine in the OlapTable config with the engine property:

import { OlapTable, ClickHouseEngines } from "@514labs/moose-lib"; interface EngineExampleRow {  id: string;  timestamp: Date;  updated_at: Date;  deleted: number;  date: Date;  page: string;  views: number;  click_sum: number;}; // MergeTree (default, can omit engine property)const MergeTree = new OlapTable<EngineExampleRow>("merge_tree_table", {  orderByFields: ["timestamp", "id"],}); // ReplacingMergeTree (deduplicate by key, optional version + soft delete)const ReplacingMergeTree = new OlapTable<EngineExampleRow>("replacing_merge_tree_table", {  engine: ClickHouseEngines.ReplacingMergeTree,  orderByFields: ["id"],  ver: "updated_at",  isDeleted: "deleted",}); // SummingMergeTree (sum numeric columns for the same key)const SummingMergeTree = new OlapTable<EngineExampleRow>("summing_merge_tree_table", {  engine: ClickHouseEngines.SummingMergeTree,  orderByFields: ["date", "page"],  columns: ["views", "click_sum"],});

Options

ClickHouseEngines includes the following categories:

MergeTree Family

  • MergeTree
  • ReplacingMergeTree
  • SummingMergeTree
  • AggregatingMergeTree
  • CollapsingMergeTree
  • VersionedCollapsingMergeTree

Replicated

  • See Replicated Engines

Special Purpose

  • S3Queue
  • S3
  • IcebergS3
  • Buffer
  • Distributed
  • Kafka

See Also

  • Tables — Full table configuration reference
  • Aggregate Types — Using SimpleAggregateFunction with AggregatingMergeTree

On this page

OptionsMergeTree FamilyReplicatedSpecial PurposeSee Also
FiveonefourFiveonefour
Fiveonefour Docs
MooseStackTemplatesGuides
Release Notes
Source523
  • Overview
Build a New App
  • 5 Minute Quickstart
  • Browse Templates
  • Existing ClickHouse
Add to Existing App
  • Next.js
  • Fastify
Fundamentals
  • Moose Runtime
  • MooseDev MCP
  • Data Modeling
Moose Modules
  • Moose OLAP
  • Moose Streaming
  • Moose Workflows
  • Moose APIs & Web Apps
Deployment & Lifecycle
  • Moose Migrate
  • Moose Deploy
Reference
  • API Reference
  • Data Types
  • Table Engines
  • CLI
  • Configuration
  • Observability Metrics
  • Help
  • Release Notes
Contribution
  • Documentation
  • Framework

You set the engine in the OlapTable config with the engine property:

import { OlapTable, ClickHouseEngines } from "@514labs/moose-lib"; interface EngineExampleRow {  id: string;  timestamp: Date;  updated_at: Date;  deleted: number;  date: Date;  page: string;  views: number;  click_sum: number;}; // MergeTree (default, can omit engine property)const MergeTree = new OlapTable<EngineExampleRow>("merge_tree_table", {  orderByFields: ["timestamp", "id"],}); // ReplacingMergeTree (deduplicate by key, optional version + soft delete)const ReplacingMergeTree = new OlapTable<EngineExampleRow>("replacing_merge_tree_table", {  engine: ClickHouseEngines.ReplacingMergeTree,  orderByFields: ["id"],  ver: "updated_at",  isDeleted: "deleted",}); // SummingMergeTree (sum numeric columns for the same key)const SummingMergeTree = new OlapTable<EngineExampleRow>("summing_merge_tree_table", {  engine: ClickHouseEngines.SummingMergeTree,  orderByFields: ["date", "page"],  columns: ["views", "click_sum"],});