ClickHouse Analytics

Demo

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---
name: ClickHouse Analytics
description: Model and query ClickHouse with the right engines, views, and projections.
---

# ClickHouse Analytics

Get fast analytical queries from ClickHouse by modeling for its columnar, sorted storage.

## Choose the right table engine

- MergeTree is the workhorse for analytical tables.
- ReplacingMergeTree deduplicates rows with the same sorting key during background merges (eventual, use FINAL or aggregation to read deduped).
- SummingMergeTree and AggregatingMergeTree pre-aggregate on merge.
- ReplicatedMergeTree variants add replication for production.

## The ORDER BY clause is the index

ClickHouse has no traditional secondary index by default; the sorting key defines the primary index and physical order.

```sql
CREATE TABLE events (
  event_date Date,
  user_id UInt64,
  event_type LowCardinality(String),… install to load the full skill