The talk at the FOSDEM conference in 2023 focused on query performance in databases. The speaker aimed to bridge the gap between the way operations people and developers think about databases. Developers often view databases as black boxes that just need to work, while operations people are concerned with internal algorithms and performance optimization. The speaker emphasized the importance of query performance from a developer's perspective, as it directly impacts the user experience. They discussed the need to consider factors like response time, error handling, and query performance distribution, rather than just looking at average response times. The speaker also highlighted the importance of capturing and analyzing query metadata, such as user, query breakdown, table involvement, and database user, to gain more insights into query performance and identify optimization opportunities. They introduced the PgStat Monitor extension for PostgreSQL as a tool to capture and analyze query performance data. In terms of optimizing queries, the speaker suggested considering different approaches based on the specific situation. In some cases, scaling up the resources may be initially required to address performance issues, while query optimization can be done in parallel. However, they stressed the importance of not being lazy and ensuring that query optimization is eventually implemented to achieve long-term performance gains. The speaker also discussed the challenges of monitoring and optimizing queries, such as bad queries affecting overall performance, considering currently running queries, and the presence of background activities and cloud-level considerations. They advised against relying solely on sampling and encouraged a comprehensive approach to monitoring and analyzing query performance. In the Q&A session, the speaker addressed topics like overhead of query monitoring, catching bad queries before production, and decision-making between query optimization and scaling resources. Overall, the talk provided insights and tools for effectively monitoring and optimizing query performance in databases.