# PolarDB PG

> Using Alibaba Cloud's open-source PolarDB for PostgreSQL kernel to provide domestic innovation qualification support, with Oracle RAC-like user experience.

---

LLMS index: [llms.txt](/llms.txt)

---

--------

## Overview

Use Pigsty and PolarDB to create PostgreSQL clusters with "domestic innovation qualification" credentials.

PolarDB for PostgreSQL now uses PostgreSQL 17 as its base.
The Pigsty `polar` template, default path, and extension notes now use PG17.
Any client tool that supports the PostgreSQL wire protocol can connect to PolarDB clusters.

Pigsty's PGSQL repository provides PolarDB PG open-source installation packages.
Pigsty does not download these packages to the local software repository during installation.

![PolarDB for PostgreSQL](/img/pigsty/polar.jpg)


--------

## Installation

Use the built-in Pigsty template:

```bash
./configure -c polar
./deploy.yml
```

--------

## Change Summary

From Pigsty v4.4, the PolarDB PG kernel uses packages that Pigsty builds and maintains.
The main changes are:

| Item | Old docs / old default | Current |
|------|-------------------------|---------|
| Kernel baseline | PostgreSQL 15 | PostgreSQL 17 |
| Default PolarDB path | `/u01/polardb_pg` | `/usr/polar-17` |
| Supported architectures | `x86_64` | `x86_64`, `aarch64` |
| Available extensions | Old docs said 61 | `pg_available_extensions` returns 93; 34 remain after filtering contrib |
| Replication user requirement | `replicator` must be `SUPERUSER` | unchanged |
{.full-width}



--------

## Configuration

Set these parameters for PolarDB database clusters:

```yaml
#----------------------------------#
# PGSQL & PolarDB
#----------------------------------#
pg_version: 17
pg_mode: polar
pg_packages: [ polardb, pgsql-common ]
pg_exporter_exclude_database: 'template0,template1,postgres,polardb_admin'
pg_default_roles:
  - { name: dbrole_readonly  ,login: false ,comment: role for global read-only access     }
  - { name: dbrole_offline   ,login: false ,comment: role for restricted read-only access }
  - { name: dbrole_readwrite ,login: false ,roles: [dbrole_readonly] ,comment: role for global read-write access }
  - { name: dbrole_admin     ,login: false ,roles: [pg_monitor, dbrole_readwrite] ,comment: role for object creation }
  - { name: postgres     ,superuser: true  ,comment: system superuser }
  - { name: replicator   ,superuser: true  ,replication: true ,roles: [pg_monitor, dbrole_readonly] ,comment: system replicator } # <- superuser is required for replication
  - { name: dbuser_dba   ,superuser: true  ,roles: [dbrole_admin]  ,pgbouncer: true ,pool_mode: session, pool_connlimit: 16 ,comment: pgsql admin user }
  - { name: dbuser_monitor ,roles: [pg_monitor] ,pgbouncer: true ,parameters: {log_min_duration_statement: 1000 } ,pool_mode: session ,pool_connlimit: 8 ,comment: pgsql monitor user }
```

The default installation directory for the `polar` kernel is now `/usr/polar-17`.
PolarDB PG still requires the `replicator` replication user to be `SUPERUSER`.
Native PostgreSQL does not have this requirement.





--------

## Available Extensions

The PolarDB PG kernel has **93** available extensions.
The following table lists the extra extensions, excluding bundled PG Contrib extensions:

| Extension | Version | Description |
|:----------|:--------|:------------|
| [hll](/ext/e/hll) | `2.18` | type for storing hyperloglog data |
| [ip4r](/ext/e/ip4r) | `2.4` |  |
| [log_fdw](/ext/e/log_fdw) | `1.4` | foreign-data wrapper for Postgres log file access |
| pase | `0.0.1` | ant ai similarity search |
| [pg_bigm](/ext/e/pg_bigm) | `1.2` | text similarity measurement and index searching based on bigrams |
| [pg_cron](/ext/e/pg_cron) | `1.5` | Job scheduler for PostgreSQL |
| pg_cron_preload | `1.0` | polardb pg extend catalog |
| [pg_hint_plan](/ext/e/pg_hint_plan) | `1.7.0` | optimizer hints for PostgreSQL |
| pg_jieba | `1.1.0` | a parser for full-text search of Chinese |
| [pg_partman](/ext/e/pg_partman) | `5.2.4` | Extension to manage partitioned tables by time or ID |
| [pg_profile](/ext/e/pg_profile) | `4.10` | PostgreSQL load profile repository and report builder |
| [pg_repack](/ext/e/pg_repack) | `1.5.1-1` | Reorganize tables in PostgreSQL databases with minimal locks |
| [pg_similarity](/ext/e/pg_similarity) | `1.0` | support similarity queries |
| [pg_squeeze](/ext/e/pg_squeeze) | `1.9` | A tool to remove unused space from a relation. |
| [pg_stat_kcache](/ext/e/pg_stat_kcache) | `2.3.0` | Kernel statistics gathering |
| [pgaudit](/ext/e/pgaudit) | `17.1` | provides auditing functionality |
| [pgtap](/ext/e/pgtap) | `1.3.3` | Unit testing for PostgreSQL |
| [pldbgapi](/ext/e/pldbgapi) | `1.1` | server-side support for debugging PL/pgSQL functions |
| polar_advisor | `1.1` | polar_advisor |
| polar_feature_utils | `1.0` | PolarDB feature utilization |
| polar_io_stat | `1.0` | polar io stat in multi dimension |
| polar_monitor | `1.3` | monitor functions for PolarDB |
| polar_monitor_preload | `1.0` | examine the polardb information |
| polar_parameter_manager | `1.2` | Extension to select parameters for manger. |
| polar_proxy_utils | `1.0` | Extension to provide operations about proxy. |
| polar_resource_manager | `1.0` | a background process that forcibly frees user session process memory |
| polar_smgrperf | `1.0` | smgr perf test extension |
| polar_tde_utils | `1.0` | Internal extension for TDE |
| polar_vfs | `1.0` | polar virtual file system for different storage |
| polar_worker | `1.1` | polar_worker |
| [prefix](/ext/e/prefix) | `1.2.0` | Prefix Range module for PostgreSQL |
| [roaringbitmap](/ext/e/roaringbitmap) | `0.5` | support for Roaring Bitmaps |
| [sequential_uuids](/ext/e/sequential_uuids) | `1.0.3` | generator of sequential UUIDs |
| varbitx | `1.1` | varbit functions pack |
{.full-width}