Data growth has been tremendous in the last decade and has no signs of stopping. To deal with this trend, database technologies have implemented a number of approaches and allowing for data compression is by far the most common and important. Yes compression in open source databases is complicated, however there is a lot of different approaches with their own implications.

In this talk we will perform a survey of compression in some of the most popular open source database engines including Innodb, TokuDB, MongoDB, WiredTiger, RocksDB, and PostgreSQL.