ALTER EXTENSION

Function

ALTER EXTENSION modifies the plug-in extension.

Precautions

ALTER EXTENSION modifies the definition of an installed extension. Methods are as follows:

• UPDATE

  The extension is updated to a new version. The extension must be applicable to an update script (or a series of scripts) so that the current installation version can be modified to a required version.

• SET SCHEMA

  The extended object is moved to another schema. This extension must be relocatable to make the command successful.

• ADD member_object

  An existing object is added to the extension. This is mainly useful for extension update scripts. This object is then treated as a member of the extension. Obviously, the object can only be canceled by canceling the extension.

• DROP member_object

  A member object is removed from the extension. This method is useful in extension update scripts. The object is not canceled, but is simply separated from the extension.

  You must have an extension before using ALTER EXTENSION. You must have the permission on adding or deleting an object before using the ADD or DROP statement.

Syntax

AlterExtension ::= ALTER EXTENSION name UPDATE [ TO new_version ];

AlterExtension ::= ALTER EXTENSION name SET SCHEMA new_schema;

AlterExtension ::= ALTER EXTENSION name ADD member_object;

AlterExtension ::= ALTER EXTENSION name DROP member_object;

where member_object is:

member_object ::= AGGREGATE agg_name (agg_type [, ...] ) |
  CAST (source_type AS target_type) |
  COLLATION object_name |
  CONVERSION object_name |
  DOMAIN object_name |
  EVENT TRIGGER object_name |
  FOREIGN DATA WRAPPER object_name |
  FOREIGN TABLE object_name |
  FUNCTION function_name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) |
  MATERIALIZED VIEW object_name |
  OPERATOR operator_name (left_type, right_type) |
  OPERATOR CLASS object_name USING index_method |
  OPERATOR FAMILY object_name USING index_method |
  [ PROCEDURAL ] LANGUAGE object_name |
  SCHEMA object_name |
  SEQUENCE object_name |
  SERVER object_name |
  TABLE object_name |
  TEXT SEARCH CONFIGURATION object_name |
  TEXT SEARCH DICTIONARY object_name |
  TEXT SEARCH PARSER object_name |
  TEXT SEARCH TEMPLATE object_name |
  TYPE object_name |
  VIEW object_name

Parameter Description

• name

  Name of an installed extension.

• new_version

  New version of the extension, which can be overridden by identifiers and string literals. If a new version of the extension is not specified, ALTER EXTENSION UPDATE updates to the default version shown in the extension's control file.

• new_schema

  New schema of the extension.

• object_name

  agg_name

  function_name

  operator_name

  Names of objects that are added or removed from the extension, including names of tables, aggregations, domains, external linked lists, functions, operators, operator classes, operator families, sequences, text search objects, types, and views that can be schema-qualified.

• agg_type

  Input data type of the aggregate function. To reference a zero-parameter aggregate function, use * to replace the input data type list.

• source_type

  Name of the source data type to be forcibly converted.

• target_type

  Name of the target data type to be forcibly converted.

• argmode

  Model of the function parameter. The value can be IN, OUT, INOUT, or VARIADIC. The default value is IN. ALTER EXTENSION does not relate to the OUT parameter, because you only need to enter parameters to confirm the consistency of functions. Therefore, the IN, INOUT, and VARIADIC parameters are enough.

• argname

  Name of a function parameter. ALTER EXTENSION does not relate to the parameter name. Only the parameter data type is required to confirm the consistency of the function.

• argtype

  Data type (optionally schema-qualified) of a function parameter.

• left_type

  right_type

  Data type (optionally schema-qualified) of an operator parameter. NONE is written for a missing parameter of a prefix or suffix operator.

Example

Update the hstore extension to version 2.0.

ALTER EXTENSION hstore UPDATE TO '2.0';

Run the following command to update the hstore extension mode to utils.

ALTER EXTENSION hstore SET SCHEMA utils;

Add an existing function for hstore extension.

ALTER EXTENSION hstore ADD FUNCTION populate_record(anyelement, hstore);