title: How does database views keep the fast query speed when multiple FK-PK relationships among all the tables
body: <p>These days I've faced performance issues when binding data with Java object to database. Especially when paring the data from database to java code when a lot of FK-PK relationship involved. I realized the issue and solved the performance slowdown by creating database views and create POJOs to map with the view. </p>
  
  <p>I did some research online but couldn't find a good answer for this: How does database(I am using mysql) keeps the fast data querying speed in views? </p>
  
  <p>For example, if I create a view among 10 tables, with FK-PK relationship, the view is still pretty fast to query and display the result pretty fast. How exactly happened behind the scenes for the database engine? </p>