In Data Platform System with ClickHouse, rather than extracting data from ClickHouse for processing in external systems, we can perform transformations directly within ClickHouse itself. ClickHouse can call any external executable program or script to process data. My idea is using custom **User-Defined Functions (UDFs) written in Rust** to handle data transformations between tables.
Now you have a large single node cluster with a ReplacingMergeTree table that can deduplicate itself. This time, you need more replicated nodes to serve more data users or improve the high availability.
My favorite ClickHouse table engine is `ReplacingMergeTree`. The main reason is that it is similar to `MergeTree` but can automatically deduplicate based on columns in the `ORDER BY` clause, which is very useful.
After starting this series ClickHouse on Kubernetes, you can now configure your first single-node ClickHouse server. Let's dive into creating your first table and understanding the basic concepts behind the ClickHouse engine, its data storage, and some cool features
Now that you have your first ClickHouse instance on Kubernetes and are starting to use it, you need to monitoring and observing what happens on it is an important task to achieve stability.
ClickHouse has been both exciting and incredibly challenging based on my experience migrating and scaling from Iceberg to ClickHouse, zero to a large cluster of trillions of rows. I have had to deal with many of use cases and resolve issues. I have been trying to take notes every day for myself, although it takes time to publish them as a series of blog posts. I hope I can do so on this ClickHouse on Kubernetes series.
OpenDAL is a data access layer that allows users to easily and efficiently retrieve data from various storage services in a unified way such as S3, FTP, FS, Google Drive, HDFS, etc. They has been rewritten in Rust for the Core and have a binding from many various language like Python, Node.js, C, etc..