Logical backup and recovery for PolarDB for PostgreSQL (Compatible with Oracle) - Data Management

Data Disaster Recovery supports logical backup and restoration for PolarDB for PostgreSQL (Compatible with Oracle) databases, including single-table restoration, geo-redundancy, and long-term archiving. This topic describes how to configure a backup schedule and restore your database when needed.

Key facts about logical backup for this database type:

Incremental backup is not supported. Only full backup is available.
Databases created after a backup schedule is configured are not included automatically. You must add them manually.
If a previous full backup is still running at the scheduled start time, the next backup is skipped.

Prerequisites

Before you begin, ensure that you have:

A backup schedule purchased for PolarDB for PostgreSQL (Compatible with Oracle). When purchasing, set Data Source Type to Oracle and Backup Method to Logical Backup. See Create a backup schedule.
A database account with read permissions on the source database.
(For restoration) A running destination database instance that is accessible.

Configure a backup schedule

Log on to the Data Management (DMS) console V5.0.
In the top navigation bar, choose Security and Specifications (DBS) > Disaster Recovery for Data (DBS) > Backup Plan.

If you use the DMS console in simple mode, move the pointer over the icon in the upper-left corner and choose All Features > Security and Specifications (DBS) > Disaster Recovery for Data (DBS) > Backup Plan.
On the Backup Schedules page, find the backup schedule you want to configure and click Configure Backup Schedule in the Actions column.

In the Configure Backup Source and Destination step, set the parameters described in the following table, then click Next.

Section	Parameter	Description
N/A	Schedule name	A name for the backup schedule. Data Disaster Recovery generates a name automatically. Use a descriptive name to identify the schedule easily. Names do not need to be unique.
Backup source information	Backup mode	The backup method. The default is the method selected when you purchased the schedule. This example uses Logical Backup.
	Database location	The location of the source database. Select PolarDB.
	Instance region	The region where the source database instance resides.
	Database type	The type of the source database. Default: PolarDB for PostgreSQL.
	PolarDB instance ID	The ID of the PolarDB cluster where the source database is deployed.
	Database name	The name of the source database.
	Database account	The username of the account used to connect to the source database. The account must have read permissions.
	Password	The password for the database account. After entering the credentials, click Test Connection to verify. A Test Passed message confirms the connection. If Test Failed appears, click Check and correct the configuration.
	Compliance warranty regarding cross-border data transfers	Select the check box to acknowledge and agree to the compliance commitment.
Backup destination information	Backup storage type	Where backup data is stored. Options: DBS Storage (recommended) — Data Disaster Recovery stores the data without requiring you to create an Object Storage Service (OSS) bucket; you are charged based on storage volume. See Storage fees. OSS For User — You must create a bucket in the OSS console in advance (Standard storage class only). See Create buckets. If you select OSS For User, configure the OSS Bucket Name parameter. For large data volumes, consider purchasing a subscription storage plan to reduce costs compared to pay-as-you-go.
	Storage encryption	The encryption method for stored backup data. Encrypted (recommended) — Uses AES-256 with OSS server-side encryption. See Server-side encryption. Non-encrypted — Data is stored without encryption.

In the Edit Backup Objects step, select the databases or tables to back up from the Available section and click the rightwards arrow to add them to the Selected section. Then click Next.

- Data Disaster Recovery supports backing up a single table, a single database, or multiple databases. Click Select All in the lower-left corner of the Available section to select all databases. The supported backup objects vary by database type. See Supported database types and features. - Databases created after the backup schedule is set up are not included automatically. To add them, update the backup objects on the Configure Task page. See Modify backup objects.

In the Configure Backup Time step, set the parameters described in the following table, then click Next.

Parameter	Description
Full-scale backup frequency	How often to run the backup. Periodic Backup runs on a recurring schedule (requires Full Data Backup Recurrence and Start At). Single Backup runs once.
Full data backup recurrence	The days of the week to run the backup. Select at least one day.
Start at	The time the backup begins. Schedule during off-peak hours to minimize database impact — for example, 01:00. If a previous full backup is still running at the scheduled start time, the next backup is skipped.
Incremental backup	Not supported for PolarDB for PostgreSQL (Compatible with Oracle).
Maximum concurrent threads for full data backup	The maximum number of threads used during a full backup. Reduce this value to minimize the impact on your database. The actual maximum depends on your backup schedule specifications. See How do I change the maximum backup speed?
Backup network speed limit	The maximum network bandwidth for backups, in MB/s. The default value 0 means unlimited. Adjust based on your business needs.

In the Edit Lifecycle step, configure the retention period for full backup sets in the Configure Full Data Backup Lifecycle section. For details on lifecycle management, see How do I manage the lifecycle rules of backup sets?
Click Precheck in the lower-right corner of the page.
When the Precheck Passed message appears, click Start Task. The backup schedule status changes to Running when it takes effect.

If an error occurs when starting the backup schedule, resolve it as soon as possible. See How do I fix errors for an abnormal backup schedule?. If the issue persists, contact technical support in the DingTalk group (ID: 35585947).

Restore a PolarDB for PostgreSQL (Compatible with Oracle) database

Log on to the DMS console V5.0.
In the top navigation bar, choose Security and Specifications (DBS) > Disaster Recovery for Data (DBS) > Backup Plan.

If you use the DMS console in simple mode, move the pointer over the icon in the upper-left corner and choose All Features > Security and Specifications (DBS) > Disaster Recovery for Data (DBS) > Backup Plan.
On the Backup Schedules page, find the backup schedule and click Manage in the Actions column.
On the Configure Task page, click Restore Database in the upper-right corner.

In the Set Time Restored To step, set the parameters described in the following table, then click Next.

Section	Parameter	Description
N/A	Task name	A name for the restoration task. Data Disaster Recovery generates a name automatically. Use a descriptive name to identify the task. Names do not need to be unique.
Configure destination database	Database location	The location of the destination database. Make sure the destination database is running. Options: User-Created Database with Public IP Address \<IP Address:Port Number\>, ECS-Hosted Database, Express Connect DB/VPN Gateway/Intelligent Gateway, PolarDB, No public network IP: Port's self-built database (accessed through the database gateway).
	Database type	The type of the destination database. Default: Oracle.
	Instance region	The region of the destination database. Displayed only when Database Location is ECS-Hosted Database, PolarDB, or the database gateway option.
	Address	The public endpoint of the destination database. Displayed only when Database Location is User-Created Database with Public IP Address, Express Connect DB/VPN Gateway/Intelligent Gateway, or the database gateway option.
	Port number	The port for the destination database. Not displayed by default when Database Location is PolarDB.
	ECS instance ID	The ID of the Elastic Compute Service (ECS) instance hosting the destination database. Displayed only when Database Location is ECS-Hosted Database.
	PolarDB instance ID	The ID of the PolarDB cluster hosting the destination database. Displayed only when Database Location is PolarDB.
	Peer VPC	The virtual private cloud (VPC) of the destination database. Displayed only when Database Location is Express Connect DB/VPN Gateway/Intelligent Gateway.
	Gateway instance ID	The ID of the database gateway. Displayed only when Database Location is the database gateway option.
	SID	The system identifier (SID) of the destination database.
	Database account	The username of the account used to connect to the destination database.
	Password	The password for the database account. After entering the credentials, click Test Connection to verify. A Test Passed message confirms the connection. If Test Failed appears, click Check and correct the configuration.
	Compliance warranty regarding cross-border data transfers	Select the check box to acknowledge and agree to the compliance commitment.

In the Configure Objects to Restore step, set the parameters described in the following table, then click Precheck.

Parameter	Description
Conflict handling	Determines how to handle naming conflicts between restored objects and existing objects in the destination database. Default: Rename Object with the Same Name — for example, if the `job_info` table conflicts, the restored table is renamed to `job_info_dbs_<Restore task ID>_<Timestamp>`.
Objects to restore	Select the databases or tables to restore from the Available section and click the rightwards arrow to add them to the Selected section. Data Disaster Recovery supports restoring at the table or database level to minimize data transfer and reduce the recovery time objective (RTO). See Supported database types and features.

When the Precheck Passed message appears in the Precheck dialog box, click Start Task.

To monitor the restoration progress, click Restore Tasks in the left-side navigation pane.

Restoration time depends on the backup schedule specifications and the size of the database. Higher-specification backup schedules complete restoration faster. See Performance tests on logical backup and physical backup.

FAQ

Why does the precheck fail with a "Database Permissions Check" error?

What's next

Call the CreateBackupPlan API operation to create a backup schedule, or CreateAndStartBackupPlan to create, configure, and start one in a single call.
Modify the backup source, backup objects, backup time, or retention policy of an existing schedule. See Manage a backup schedule.
Review charges for your backup schedule. See Billing FAQ.
Pause a backup schedule you no longer need to avoid unnecessary charges. See Pause or start a backup schedule.