https://clickhouse.com/
GitHub: https://github.com/ClickHouse/ClickHouse
Clickhouse is a #database/OLAP, not like [[Postgres]] who is a #database/OLTP
- Column based
- Amazing at aggregates
## Pros
- Great for managing large amounts of data that doesn't change very often
- Analytics
- Finance
- Ad bidding
- Content delivery
- Log Management
- Fast for aggregates
- Base it's column-based
- In a row-based DB, averaging over a column requires accessing the column value for every row
- Scales better then [[Postgres]]
- CPU increase doesn't benefit Postgres too much, but does for Clickhouse
- Clickhouse optimize data in parallel, while Postgres is single process (per connection)
- Distributed
- Multi-master
- Cross-region
## Cons
- Terrible at mutations
- because it's column-based, inserting a row requires modifying all columns
- Often used along with other row-based DB like [[Postgres]]
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## Reference
- [YouTube | Clickhouse | What is Clickhouse?](https://youtu.be/FtoWGT7kS-c)
- [YouTube | PostHog | In-depth: ClickHouse vs PostgreSQL](https://youtu.be/iLXXoDaFoxs)
- PostHog migrated to ClickHouse to solve performance issues