Rich Raposa Director, Global Learning, ClickHouse
Projections are a query-optimization feature of MergeTree tables in ClickHouse that store data in a different format than the defined sort order. Useful use cases include the ability to sort the data in a different order than the primary key, and also to pre-aggregate columns. One nice benefit of projections over materialized views is that a projection does not require a separate table, so users simply query the original table and ClickHouse decides at query time if a projection can improve the performance.
![Powering Feature Stores with ClickHouse](/_next/image?url=https%3A%2F%2Fimg.youtube.com%2Fvi%2FY9QlYOQVmzc%2Fmaxresdefault.jpg&w=1920&q=75)
![Powering Feature Stores with ClickHouse](/_next/image?url=%2F_next%2Fstatic%2Fmedia%2Ffallback.bc43f726.png&w=1920&q=75)
Powering Feature Stores with ClickHouse
Mark Needham Principal Product Marketing Engineer, ClickHouse
![Querying archive files with ClickHouse](/_next/image?url=https%3A%2F%2Fimg.youtube.com%2Fvi%2FCiKfRMAhs3M%2Fmaxresdefault.jpg&w=1920&q=75)
![Querying archive files with ClickHouse](/_next/image?url=%2F_next%2Fstatic%2Fmedia%2Ffallback.bc43f726.png&w=1920&q=75)
Querying archive files with ClickHouse
Mark Needham Principal Product Marketing Manager, ClickHouse
![Importing Numpy array files into ClickHouse](/_next/image?url=https%3A%2F%2Fimg.youtube.com%2Fvi%2F_7mpIeig8Hw%2Fmaxresdefault.jpg&w=1920&q=75)
![Importing Numpy array files into ClickHouse](/_next/image?url=%2F_next%2Fstatic%2Fmedia%2Ffallback.bc43f726.png&w=1920&q=75)
Importing Numpy array files into ClickHouse
Mark Needham Principal Product Marketing Manager, ClickHouse