Overview of Ecto 3.0 Enhancements

This blog post authored by José Valim offers an in-depth look at the changes and enhancements introduced in Ecto 3.0. One of the key highlights is the considerable reduction in memory usage due to the optimized handling of schema metadata. Another significant improvement is the caching of statements for insert, update, and delete operations, which has notably boosted performance. The introduction of the `Repo.checkout` function allows for more efficient use of database connections by keeping them 'warm'. Ecto 3.0 also brings new options for handling upserts and provides better logging and warnings in migrations to aid developers. The improvements have been well-received, with some large projects already upgrading to this version with minimal effort.