Amazon RDS - PostgreSQL Features

Amazon RDS – PostgreSQL Features

PostgreSQL is a strong, open supply object-relational database system which has earned a robust fame for reliability, function robustness, and efficiency. AWS RDS runs varied variations of PostgreSQL. It helps point-in-time restore and backups, creation of DB snapshots and operating it on a multi-AZ surroundings.

Supported Variations

The variations 9.three by means of 10.four are the foremost variations supported within the RDS platform. If no model is talked about in the course of the DB creation, it defaults to the newest model at that cut-off date. Beneath is an instance of find out how to get all supported DB Engine variations utilizing AWS API in a python SDK program.


import boto3
consumer = boto3.consumer('rds')
response = consumer.describe_db_engine_versions(
    ListSupportedCharacterSets=False, #True,


After we run the above program, we get the next output −


   "ResponseMetadata": {
      "RetryAttempts": 0,
      "HTTPStatusCode": 200,
      "RequestId": "c85cd49f-2c16-44b4-9890-cb233651f962",
      "HTTPHeaders": {
         "x-amzn-requestid": "c85cd49f-2c16-44b4-9890-cb233651f962",
         "date": "Fri, 14 Sep 2018 07:31:34 GMT",
         "content-length": "995",
         "content-type": "textual content/xml"
   "u'DBEngineVersions'": [
         "u'Engine'": "postgres",
         "u'DBParameterGroupFamily'": "postgres10",
         "u'SupportsLogExportsToCloudwatchLogs'": false,
         "u'SupportsReadReplica'": true,
         "u'DBEngineDescription'": "PostgreSQL",
         "u'EngineVersion'": "10.4",
         "u'DBEngineVersionDescription'": "PostgreSQL 10.4-R1",
         "u'ValidUpgradeTarget'": []

Database Preview Setting

The PostgreSQL neighborhood releases new variations and new extensions repeatedly. You’ll be able to check out new PostgreSQL variations and extensions earlier than they’re absolutely supported by Aws RDS. To try this, you’ll be able to create a brand new DB occasion within the Database Preview Setting.

DB situations within the Database Preview Setting are just like DB situations in a manufacturing surroundings. Nonetheless, bear in mind a number of essential elements:

  • All DB situations are deleted 60 days after you create them, together with any backups and snapshots.
  • You’ll be able to solely create a DB occasion in a digital personal cloud (VPC) primarily based on the Amazon VPC service.
  • You’ll be able to solely create M4, T2, and R4 occasion sorts. For extra details about RDS occasion lessons,
  • You’ll be able to’t get assist from AWS Assist with DB situations. You’ll be able to submit your questions within the RDS Database Preview Setting Discussion board.
  • You’ll be able to solely use Common Objective SSD and Provisioned IOPS SSD storage.
  • You’ll be able to’t copy a snapshot of a DB occasion to a manufacturing surroundings.
  • Some Amazon RDS options aren’t accessible within the preview surroundings, as described following.

Logical Replication

Logical replication is a technique of replicating knowledge objects and their adjustments, primarily based upon their replication id (normally a main key). Logical replication makes use of a publish and subscribe mannequin with a number of subscribers subscribing to a number of publications on a writer node. Subscribers pull knowledge from the publications they subscribe to and should subsequently re-publish knowledge to permit cascading replication or extra advanced configurations. It’s used for the under actions.

  • Sending incremental adjustments in a single database or a subset of a database to subscribers as they happen.
  • Consolidating a number of databases right into a single one (for instance for analytical functions).
  • Replicating between totally different main variations of PostgreSQL.
  • Replicating between PostgreSQL situations on totally different platforms (for instance Linux to Home windows)
  • Giving entry to replicated knowledge to totally different teams of customers.
  • Sharing a subset of the database between a number of databases.

To allow logical replication for an Amazon RDS for PostgreSQL DB occasion

  • The AWS person account requires the rds_superuser function to carry out logical replication for the PostgreSQL database on Amazon RDS.
  • Set the rds.logical_replication parameter to 1.
  • Modify the inbound guidelines of the safety group for the writer occasion (manufacturing) to permit the subscriber occasion (duplicate) to attach. That is normally completed by together with the IP tackle of the subscriber within the safety group.