Why is ClickHouse suitable for storing trip history in Yandex.Taxi? Would reading specific user trips be a problem?

ClickHouse is excellent for storing the history of trips in Yandex.Taxi because it is a columnar analytical database optimized for fast reading of large volumes of data and aggregations. Trip history is a massive stream of events where the speed of analytics and the ability to quickly generate reports are important.

The problem of reading specific user trips is solved by proper indexing and data partitioning. In ClickHouse, primary keys and partitions by user_id or date can be used, which allows for efficient filtering of data by user and quickly retrieving the necessary records.

Thus, despite ClickHouse not being a transactional database, it is very suitable for analytics and storing trip history with quick user access.