The query plan cache
This is the 3rd in a series of posts about query plans. The first post covered what a query plan is and how to read it. The second post described the effort required to make a query plan. This post will cover the plan cache. If your server is running SQL Server 2016+ and you have enabled query store please STOP READING this post. Seriously. Query store changes and supersedes much of the information in this post. Instead, read about query store from the expert herself, Erin Stellato. The plan cache is a list of query plans that have been compiled by the optimizer andRead More →