Amazon RDS PostgreSQL (Edge)

Prerequisites

• The IP address or hostname and port number of your Amazon RDS PostgreSQL server are available.

• The Amazon RDS PostgreSQL server version is 10.0 or higher.

• Hevo’s IP address(es) for your region is added to the Amazon RDS PostgreSQL database IP Allowlist.

• Log-based incremental replication is enabled on the primary instance of your Amazon RDS PostgreSQL database server.

  Note: PostgreSQL versions 15.8 and lower do not support logical replication on read replicas. This feature is available in versions 16 and higher.

• A non-administrative database user for Hevo is created in your Amazon RDS PostgreSQL database instance. You must have the Superuser or CREATE ROLE privileges to add a new user.

• The SELECT, USAGE, and CONNECT privileges are granted to the database user.

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Perform the following steps to configure your Amazon RDS PostgreSQL Source:

Set up Logical Replication for Incremental Data

Hevo supports data replication from PostgreSQL servers using the pgoutput plugin (available on PostgreSQL version 10.0 and above). For this, Hevo identifies the incremental data from publications, which are defined to track changes generated by all or some database tables. A publication identifies the changes generated by the tables from the Write Ahead Logs (WALs) set at the logical level.

Perform the following steps to enable logical replication on your Amazon RDS PostgreSQL server:

1. Create a parameter group

1. Log in to the Amazon RDS console.

2. In the left navigation pane, click Parameter groups.

3. On the Parameter groups page, click Create parameter group.

   

4. On the Create parameter group page, perform the following steps:

   1. Select a postgresql version from the Parameter group family drop-down.

      

   2. Select DB Parameter Group from the Type drop-down.

      

   3. Specify the Group name and Description, and then click Create.

      

You have successfully created a parameter group.

2. Configure the replication parameters

1. On the Parameter groups page, select the check box corresponding to the parameter group that you created above.

   

2. In the Actions drop-down, click Edit.

   

3. On the page that appears, search and update the value of the following parameters:

   

   Parameter	Value	Description
   max_replication_slots	5	The number of clients that can connect to the server. Default value: 20. RDS recommends setting this parameter value to more than or equal to the number of planned publications and subscriptions so that internal replication by RDS is not affected.
   rds.logical_replication	1	The setting to enable or turn off logical replication. The default value for this parameter is 0, which means logical replication is turned off. To enable logical replication, a value of 1 is required.
   max_wal_senders	5	The maximum number of processes that can simultaneously transmit the WAL. Default value: 10. RDS recommends setting this value to at least 5 so that its internal replication is not affected.
   wal_sender_timeout	0	The time after which PostgreSQL terminates the replication connections due to inactivity. A time value specified without units is assumed to be in milliseconds. Default value: 60 seconds. You must set the value to 0 so that the connections are never terminated, and your Pipeline does not fail.

3. Apply the parameter group to your PostgreSQL database

1. In your Amazon RDS console, click Databases in the left navigation pane.

2. On the Databases page, click the DB identifier for your database, and then Modify.

3. Scroll to the Additional configuration section, and in the Database options, do the following:

   

   1. From the drop-down, select the DB parameter group you created in Step 1.

   2. Set the Backup retention period to at least 3 days. This setting defines the number of days for which automated backups are retained. Default value: 1.

4. Click Continue.

5. On the Modify DB instance: <your database instance> page, in the Schedule modifications section, select the time window for applying the changes and click Modify DB instance.

   

6. Once the DB parameter group status changes to Pending reboot, reboot the DB instance for the changes to take effect. You can check this from the Configuration tab of your database instance.

   

4. Create a publication for your database tables

In PostgreSQL 10 onwards, the data to be replicated is identified via publications. A publication must be defined on the primary database instance and can include some or all the database tables. The publication is a group of tables that tracks and determines the set of changes generated by those tables from the Write-Ahead Logs (WALs).

To define a publication:

Note: You must define a publication with the insert, update, and delete privileges.

1. Connect to your Amazon RDS PostgreSQL primary database instance as a Superuser with an SQL client tool, such as psql.

2. Run one of the following commands to create a publication:

   Note: You can create multiple distinct publications whose names do not start with a number in a single database.

   • For one or more database tables:

     CREATE PUBLICATION <publication_name> FOR TABLE <table_1>, <table_4>, <table_5>;
     

   • For all database tables:

     Note: You can run this command only as a Superuser.

     CREATE PUBLICATION <publication_name> FOR ALL TABLES;
     

3. (Optional) Run the following command to add table(s) to or remove them from a publication:

   Note: You can modify a publication only if it is not defined on all tables and you have ownership rights on the table(s) being added or removed.

   ALTER PUBLICATION <publication_name> ADD/DROP TABLE <table_name>;
   

   When you alter a publication, you must refresh the schema for the changes to be visible in your Pipeline.

4. (Optional) Run the following command to create a publication on a column list:

   Note: This feature is available in PostgreSQL versions 15 and higher.

   CREATE PUBLICATION <columns_publication> FOR TABLE <table_name> (<column_name1>, <column_name2>, <column_name3>, <column_name4>,...);
   
   -- Example to create a publication with three columns
   
   CREATE PUBLICATION film_data_filtered FOR TABLE film (film_id, title, description);
   

   Run the following command to alter a publication created on a column list:

   ALTER PUBLICATION <columns_publication> SET TABLE <table_name> (<column_name1>, <column_name2>, ...);
   
   -- Example to drop a column from the publication created above
   
   ALTER PUBLICATION film_data_filtered SET TABLE film (film_id, title);
   

Note: Replace the placeholder values in the commands above with your own. For example, <publication_name> with hevo_publication.

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Allowlist Hevo IP addresses for your region

You must add Hevo’s IP address for your region to the database IP allowlist, enabling Hevo to connect to your Amazon RDS PostgreSQL database. To do this:

1. Add inbound rules

1. Log in to the Amazon RDS console.

2. In the left navigation pane, click Databases.

3. In the Databases section on the right, click the DB identifier of your Amazon RDS database instance.

   

4. In the Connectivity & security tab, click the link text under Security, VPC security groups.

   

5. On the Security groups page, select the check box for your Security group ID, and from the Actions drop-down, click Edit inbound rules.

   

6. On the Edit inbound rules page:

   

   1. Click Add rule.

   2. Add Hevo’s IP address for your region to allow connections to your Amazon RDS PostgreSQL database instance.

   3. Click Save rules.

2. Configure Virtual Private Cloud (VPC)

1. Follow steps 1-3 from the section above.

2. In the Connectivity & security tab, click the link text under Networking, VPC.

   

3. On the Your VPCs page, click the VPC ID, and in the Details section, click the link text under Main network ACL.

   

4. On the Network ACLs page, click the Inbound Rules tab and ensure that the IP address you added is set to Allow.

   

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Create a Database User and Grant Privileges

1. Create a database user (Optional)

2. Grant privileges to the user

The following table lists the privileges that the database user for Hevo requires to connect to and ingest data from your PostgreSQL database:

Privilege Name	Allows Hevo to
CONNECT	Connect to the specified database.
USAGE	Access the objects in the specified schema.
SELECT	Select rows from the database tables.
ALTER DEFAULT PRIVILEGES	Access new tables created in the specified schema after Hevo has connected to the PostgreSQL database.
rds_replication	Access the WALs.

Perform the following steps to grant privileges to the database user connecting to the PostgreSQL database as follows:

1. Connect to your Amazon RDS PostgreSQL database instance as a Superuser with an SQL client tool, such as psql.

2. Run the following commands to grant privileges to your database user:

   GRANT CONNECT ON DATABASE <database_name> TO <database_username>;
   GRANT USAGE ON SCHEMA <schema_name> TO <database_username>;
   GRANT SELECT ON ALL TABLES IN SCHEMA <schema_name> to <database_username>;
   

3. (Optional) Alter the schema to grant SELECT privileges on tables created in the future to your database user:

   Note: Grant this privilege only if you want Hevo to replicate data from tables created in the schema after the Pipeline is created.

   ALTER DEFAULT PRIVILEGES IN SCHEMA <schema_name> GRANT SELECT ON TABLES TO <database_username>;
   

4. Run the following command to grant your database user permission to read from the WALs:

   GRANT rds_replication TO <database_username>;
   

Note: Replace the placeholder values in the commands above with your own. For example, <database_username> with hevouser.

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Retrieve the Database Hostname and Port Number (Optional)

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