DROP EXTENSION
Function
DROP EXTENSION deletes an extension.
Precautions
- DROP EXTENSION deletes an extension from the database. When you delete an extension, the components that make up the extension are also deleted.
- The DROP EXTENSION command can be used only by the owner of the extension.
Syntax
DROP EXTENSION [ IF EXISTS ] name [, ...] [ CASCADE | RESTRICT ]
Parameter Description
- IF EXISTS - If the IF EXISTS parameter is used and the extension does not exist, no error is reported. Instead, a NOTICE is generated. 
- name - Name of an installed extension. 
- CASCADE - Automatically deletes objects that depend on the extension. 
- RESTRICT - If any object depends on an extension, the extension cannot be deleted (unless all its member objects and other extension objects are deleted at a time using the DROP command). This is a default processing. 
Examples
Delete extension hstore from the current database.
DROP EXTENSION hstore;
In the current database, if an object that uses hstore exists, this command will fail. For example, a column in any table is of the hstore type. Adding the CASCADE option can forcibly delete the extension and objects that depend on it.