Merge pull request #104791 from jonels-msft/update-extensions

Update hyperscale (citus) extensions

Author: megvanhuygen

articles/postgresql/concepts-hyperscale-extensions.md

@@ -6,15 +6,15 @@ ms.author: raagyema
 ms.service: postgresql
 ms.subservice: hyperscale-citus
 ms.topic: conceptual
-ms.date: 05/06/2019
+ms.date: 02/18/2020
 ---
 # PostgreSQL extensions in Azure Database for PostgreSQL – Hyperscale (Citus)
 
-PostgreSQL provides the ability to extend the functionality of your database by using extensions. Extensions allow for bundling multiple related SQL objects together in a single package that can be loaded or removed from your database with a single command. After being loaded in the database, extensions can function like built-in features. For more information on PostgreSQL extensions, see [Package related objects into an extension](https://www.postgresql.org/docs/9.6/static/extend-extensions.html).
+PostgreSQL provides the ability to extend the functionality of your database by using extensions. Extensions allow for bundling multiple related SQL objects together in a single package that can be loaded or removed from your database with a single command. After being loaded in the database, extensions can function like built-in features. For more information on PostgreSQL extensions, see [Package related objects into an extension](https://www.postgresql.org/docs/current/static/extend-extensions.html).
 
 ## Use PostgreSQL extensions
 
-PostgreSQL extensions must be installed in your database before you can use them. To install a particular extension, run the [CREATE EXTENSION](https://www.postgresql.org/docs/9.6/static/sql-createextension.html) command from the psql tool to load the packaged objects into your database.
+PostgreSQL extensions must be installed in your database before you can use them. To install a particular extension, run the [CREATE EXTENSION](https://www.postgresql.org/docs/current/static/sql-createextension.html) command from the psql tool to load the packaged objects into your database.
 
 Azure Database for PostgreSQL - Hyperscale (Citus) currently supports a subset of key extensions as listed here. Extensions other than the ones listed aren't supported. You can't create your own extension with Azure Database for PostgreSQL.
 
@@ -27,12 +27,13 @@ The following tables list the standard PostgreSQL extensions that are currently
 > [!div class="mx-tableFixed"]
 > | **Extension** | **Description** |
 > |---|---|
-> | [citext](https://www.postgresql.org/docs/9.6/static/citext.html) | Provides a case-insensitive character string type. |
-> | [cube](https://www.postgresql.org/docs/9.6/static/cube.html) | Provides a data type for multidimensional cubes. |
-> | [hstore](https://www.postgresql.org/docs/9.6/static/hstore.html) | Provides a data type for storing sets of key-value pairs. |
-> | [isn](https://www.postgresql.org/docs/9.6/static/isn.html) | Provides data types for international product numbering standards. |
+> | [citext](https://www.postgresql.org/docs/current/static/citext.html) | Provides a case-insensitive character string type. |
+> | [cube](https://www.postgresql.org/docs/current/static/cube.html) | Provides a data type for multidimensional cubes. |
+> | [hstore](https://www.postgresql.org/docs/current/static/hstore.html) | Provides a data type for storing sets of key-value pairs. |
+> | [hll](https://github.com/citusdata/postgresql-hll) | Provides a HyperLogLog data structure. |
+> | [isn](https://www.postgresql.org/docs/current/static/isn.html) | Provides data types for international product numbering standards. |
 > | [lo](https://www.postgresql.org/docs/current/lo.html) | Large Object maintenance. |
-> | [ltree](https://www.postgresql.org/docs/9.6/static/ltree.html) | Provides a data type for hierarchical tree-like structures. |
+> | [ltree](https://www.postgresql.org/docs/current/static/ltree.html) | Provides a data type for hierarchical tree-like structures. |
 > | [seg](https://www.postgresql.org/docs/current/seg.html) | Data type for representing line segments or floating-point intervals. |
 > | [topn](https://github.com/citusdata/postgresql-topn/) | Type for top-n JSONB. |
 
@@ -41,31 +42,31 @@ The following tables list the standard PostgreSQL extensions that are currently
 > [!div class="mx-tableFixed"]
 > | **Extension** | **Description** |
 > |---|---|
-> | [dict\_int](https://www.postgresql.org/docs/9.6/static/dict-int.html) | Provides a text search dictionary template for integers. |
+> | [dict\_int](https://www.postgresql.org/docs/current/static/dict-int.html) | Provides a text search dictionary template for integers. |
 > | [dict\_xsyn](https://www.postgresql.org/docs/current/dict-xsyn.html) | Text search dictionary template for extended synonym processing. |
-> | [unaccent](https://www.postgresql.org/docs/9.6/static/unaccent.html) | A text search dictionary that removes accents (diacritic signs) from lexemes. |
+> | [unaccent](https://www.postgresql.org/docs/current/static/unaccent.html) | A text search dictionary that removes accents (diacritic signs) from lexemes. |
 
 ### Functions extensions
 
 > [!div class="mx-tableFixed"]
 > | **Extension** | **Description** |
 > |---|---|
 > | [autoinc](https://www.postgresql.org/docs/current/contrib-spi.html#id-1.11.7.45.7) | Functions for autoincrementing fields. |
-> | [earthdistance](https://www.postgresql.org/docs/9.6/static/earthdistance.html) | Provides a means to calculate great-circle distances on the surface of the Earth. |
-> | [fuzzystrmatch](https://www.postgresql.org/docs/9.6/static/fuzzystrmatch.html) | Provides several functions to determine similarities and distance between strings. |
+> | [earthdistance](https://www.postgresql.org/docs/current/static/earthdistance.html) | Provides a means to calculate great-circle distances on the surface of the Earth. |
+> | [fuzzystrmatch](https://www.postgresql.org/docs/current/static/fuzzystrmatch.html) | Provides several functions to determine similarities and distance between strings. |
 > | [insert\_username](https://www.postgresql.org/docs/current/contrib-spi.html#id-1.11.7.45.8) | Functions for tracking who changed a table. |
 > | [intagg](https://www.postgresql.org/docs/current/intagg.html) | Integer aggregator and enumerator (obsolete). |
-> | [intarray](https://www.postgresql.org/docs/9.6/static/intarray.html) | Provides functions and operators for manipulating null-free arrays of integers. |
+> | [intarray](https://www.postgresql.org/docs/current/static/intarray.html) | Provides functions and operators for manipulating null-free arrays of integers. |
 > | [moddatetime](https://www.postgresql.org/docs/current/contrib-spi.html#id-1.11.7.45.9) | Functions for tracking last modification time. |
-> | [pgcrypto](https://www.postgresql.org/docs/9.6/static/pgcrypto.html) | Provides cryptographic functions. |
+> | [pgcrypto](https://www.postgresql.org/docs/current/static/pgcrypto.html) | Provides cryptographic functions. |
 > | [pg\_partman](https://pgxn.org/dist/pg_partman/doc/pg_partman.html) | Manages partitioned tables by time or ID. |
-> | [pg\_trgm](https://www.postgresql.org/docs/9.6/static/pgtrgm.html) | Provides functions and operators for determining the similarity of alphanumeric text based on trigram matching. |
+> | [pg\_trgm](https://www.postgresql.org/docs/current/static/pgtrgm.html) | Provides functions and operators for determining the similarity of alphanumeric text based on trigram matching. |
 > | [refint](https://www.postgresql.org/docs/current/contrib-spi.html#id-1.11.7.45.5) | Functions for implementing referential integrity (obsolete). |
 > | session\_analytics | Functions for querying hstore arrays. |
-> | [tablefunc](https://www.postgresql.org/docs/9.6/static/tablefunc.html) | Provides functions that manipulate whole tables, including crosstab. |
+> | [tablefunc](https://www.postgresql.org/docs/current/static/tablefunc.html) | Provides functions that manipulate whole tables, including crosstab. |
 > | [tcn](https://www.postgresql.org/docs/current/tcn.html) | Triggered change notifications. |
 > | [timetravel](https://www.postgresql.org/docs/current/contrib-spi.html#id-1.11.7.45.6) | Functions for implementing time travel. |
-> | [uuid-ossp](https://www.postgresql.org/docs/9.6/static/uuid-ossp.html) | Generates universally unique identifiers (UUIDs). |
+> | [uuid-ossp](https://www.postgresql.org/docs/current/static/uuid-ossp.html) | Generates universally unique identifiers (UUIDs). |
 
 ### Hyperscale extensions
 
@@ -81,15 +82,15 @@ The following tables list the standard PostgreSQL extensions that are currently
 > | **Extension** | **Description** |
 > |---|---|
 > | [bloom](https://www.postgresql.org/docs/current/bloom.html) | Bloom access method - signature file-based index. |
-> | [btree\_gin](https://www.postgresql.org/docs/9.6/static/btree-gin.html) | Provides sample GIN operator classes that implement B-tree-like behavior for certain data types. |
-> | [btree\_gist](https://www.postgresql.org/docs/9.6/static/btree-gist.html) | Provides GiST index operator classes that implement B-tree. |
+> | [btree\_gin](https://www.postgresql.org/docs/current/static/btree-gin.html) | Provides sample GIN operator classes that implement B-tree-like behavior for certain data types. |
+> | [btree\_gist](https://www.postgresql.org/docs/current/static/btree-gist.html) | Provides GiST index operator classes that implement B-tree. |
 
 ### Language extensions
 
 > [!div class="mx-tableFixed"]
 > | **Extension** | **Description** |
 > |---|---|
-> | [plpgsql](https://www.postgresql.org/docs/9.6/static/plpgsql.html) | PL/pgSQL loadable procedural language. |
+> | [plpgsql](https://www.postgresql.org/docs/current/static/plpgsql.html) | PL/pgSQL loadable procedural language. |
 
 ### Miscellaneous extensions
 
@@ -100,15 +101,15 @@ The following tables list the standard PostgreSQL extensions that are currently
 > | [amcheck](https://www.postgresql.org/docs/current/amcheck.html) | Functions for verifying relation integrity. |
 > | [file\_fdw](https://www.postgresql.org/docs/current/file-fdw.html) | Foreign-data wrapper for flat file access. |
 > | [pageinspect](https://www.postgresql.org/docs/current/pageinspect.html) | Inspect the contents of database pages at a low level. |
-> | [pg\_buffercache](https://www.postgresql.org/docs/9.6/static/pgbuffercache.html) | Provides a means for examining what's happening in the shared buffer cache in real time. |
+> | [pg\_buffercache](https://www.postgresql.org/docs/current/static/pgbuffercache.html) | Provides a means for examining what's happening in the shared buffer cache in real time. |
 > | [pg\_cron](https://github.com/citusdata/pg_cron) | Job scheduler for PostgreSQL. |
 > | [pg\_freespacemap](https://www.postgresql.org/docs/current/pgfreespacemap.html) | Examine the free space map (FSM). |
-> | [pg\_prewarm](https://www.postgresql.org/docs/9.6/static/pgprewarm.html) | Provides a way to load relation data into the buffer cache. |
-> | [pg\_stat\_statements](https://www.postgresql.org/docs/9.6/static/pgstatstatements.html) | Provides a means for tracking execution statistics of all SQL statements executed by a server. See the "pg_stat_statements" section for information about this extension. |
+> | [pg\_prewarm](https://www.postgresql.org/docs/current/static/pgprewarm.html) | Provides a way to load relation data into the buffer cache. |
+> | [pg\_stat\_statements](https://www.postgresql.org/docs/current/static/pgstatstatements.html) | Provides a means for tracking execution statistics of all SQL statements executed by a server. See the "pg_stat_statements" section for information about this extension. |
 > | [pg\_visibility](https://www.postgresql.org/docs/current/pgvisibility.html) | Examine the visibility map (VM) and page-level visibility information. |
-> | [pgrowlocks](https://www.postgresql.org/docs/9.6/static/pgrowlocks.html) | Provides a means for showing row-level locking information. |
-> | [pgstattuple](https://www.postgresql.org/docs/9.6/static/pgstattuple.html) | Provides a means for showing tuple-level statistics. |
-> | [postgres\_fdw](https://www.postgresql.org/docs/9.6/static/postgres-fdw.html) | Foreign-data wrapper used to access data stored in external PostgreSQL servers. See the "dblink and postgres_fdw" section for information about this extension.|
+> | [pgrowlocks](https://www.postgresql.org/docs/current/static/pgrowlocks.html) | Provides a means for showing row-level locking information. |
+> | [pgstattuple](https://www.postgresql.org/docs/current/static/pgstattuple.html) | Provides a means for showing tuple-level statistics. |
+> | [postgres\_fdw](https://www.postgresql.org/docs/current/static/postgres-fdw.html) | Foreign-data wrapper used to access data stored in external PostgreSQL servers. See the "dblink and postgres_fdw" section for information about this extension.|
 > | [sslinfo](https://www.postgresql.org/docs/current/sslinfo.html) | Information about SSL certificates. |
 > | [tsm\_system\_rows](https://www.postgresql.org/docs/current/tsm-system-rows.html) | TABLESAMPLE method, which accepts number of rows as a limit. |
 > | [tsm\_system\_time](https://www.postgresql.org/docs/current/tsm-system-time.html) | TABLESAMPLE method, which accepts time in milliseconds as a limit. |