Summary
This chapter started with tuning queries and continued with how caching benefits the execution of a query. So simply writing a query and expecting a good performance is not always enough. There are multiple ways to tune queries for better performance, which we covered them in this chapter, to help you write queries. We also covered how to tweak the configuration settings to get the best performance from disks, and how to use Optimizer hints to let it choose the best plan. We discussed generating and reading Explain Plan, and each node in the Explain Plan. In the next chapter, we will cover in-built extensions in PostgreSQL, how to build contrib modules, and dblinks. These days many applications need images to be stored in their database as part of their operations, so we will also cover large objects in the next chapter.