In this chapter, indexes, views, functions, user-defined data types, and rule and trigger systems have been discussed. A view is a named query or a wrapper around a SELECT statement. They can be used as a data access layer, provide an abstraction level, and control data privileges and permissions.
A view in PostgreSQL can be categorized as temporary, materialized, updatable, and recursive. Simple views in PostgreSQL are automatically updatable. To make complex views updatable, one can use the rule and trigger systems. Indexes are physical database objects defined on a table column, a set of columns, and expressions. Indexes are often used to optimize performance or to validate data. There are several techniques for building indexes, including B-tree, hash, GIN, GIST, and BRIN. B-tree is the default indexing method. GIN and GIST are useful for indexing complex data types and for full-text searches. There are several types of indexes; each type can be used for a different use case....
