Share your experience working with the PostgreSQL database, including tasks implemented and problems solved.

In my work with PostgreSQL, I was involved in creating and optimizing queries for test scenarios, as well as preparing test data. For example, I implemented complex queries using JOINs and subqueries to verify the correctness of business logic.

One of the problems I solved was optimizing slow queries: I analyzed execution plans using EXPLAIN and added necessary indexes, which significantly sped up the tests.

I also automated data integrity checks using transactions and rollbacks so that tests did not affect each other and the database remained in a consistent state.