> For the complete documentation index, see [llms.txt](https://vikram-bajaj.gitbook.io/cs-gy-6083-principles-of-database-systems/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://vikram-bajaj.gitbook.io/cs-gy-6083-principles-of-database-systems/sql/intermediate-sql/more-sql-data-types-and-schemas/other-features.md).

# Other Features

* **default** can be used to set a default value for an attribute
* `create index<index_name> on <relation_name>(<attribute_name>)` can be used to create an index for an attribute of a relation
* Large objects are stored as “large object”
  * **blob** (**b**inary **l**arge **ob**ject): object is a large collection of uninterpreted binary data whose interpretation is left to an application outside of the database system – video, image, etc
  * **clob** (**c**haracter **l**arge **ob**ject): object is a large collection of char data – book review, book content, etc
  * When a query returns a large object, a pointer is returned rather than the large object itself
* create type can be used to create a user-defined data type:

  ```
  create type Dollars as numeric (12,2) final
  ```
* create domain can be used to create user-defined domains:

  ```
  create domain person_name char(20) not null
  ```


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