Help Center/ Document Database Service/ User Guide/ Data Backups/ Performing Backups/ Configuring Sparse Backup Policies
Updated on 2026-05-11 GMT+08:00
View PDF
Share

Configuring Sparse Backup Policies

Scenarios

If you want to retain backups for a long time, you can enable sparse backup to reduce costs. Compared with the standard backup policy, sparse backup policies reduce the automated backup frequency while maintaining the same retention period for the backups.

To enable sparse backup, submit a service ticket.

Differences Between Standard Backup and Sparse Backup

Item

Standard Backup

Sparse Backup

Description

DDS uses standard backup by default. A standard backup saves all data of an instance based on your chosen schedule and backup cycle. Each time a backup task finishes, the system creates a backup and stores it for the duration you specify.

An instance can have only one standard backup policy.

Compared with the default backup policy, sparse backup policies reduce the backup frequency while maintaining the same retention period for the backups.

An instance can have up to 10 sparse backup policies.

Backup Cycle

Weekly: Select at least one day in a week.
The following types of sparse backup policies are supported:
  • Weekly: Select at least one day in a week.
  • Monthly: Select at least one day in a month.
  • Yearly: Select a specific day in a year.

Retention Period

Number of days that your automated backups can be retained. The retention period is from 1 to 732 days and the default value is 7.

  • Extending the retention period improves data availability, so set an appropriate retention period for your workloads.
  • If you shorten the retention period, the new backup policy will apply to existing backups. Any automated backups (both full and incremental backups) exceeding the new retention period will be deleted immediately. Manual backups will not be deleted automatically.

Number of days that your sparse backups can be retained. The retention period is from 1 to 732 days.

  • Extending the retention period improves data availability, so set an appropriate retention period for your workloads.
  • If you shorten the retention period, the new backup policy will apply to backups generated under this policy. Any automated backups (both full and incremental backups) exceeding the new retention period will be deleted immediately. Manual backups will not be deleted automatically.

Time Window

A one-hour period the backup will be scheduled within 24 hours, such as 01:00-02:00.

The time window of the sparse backup policy is the same as that of the standard backup policy.

A one-hour period the backup will be scheduled within 24 hours, such as 01:00-02:00.

Billing

For details, see Billing in "Configuring an Automated Backup Policy."

Procedure

  1. Log in to the management console.
  2. Click in the upper left corner and select a region and a project.
  3. Click in the upper left corner of the page and choose Databases > Document Database Service.
  4. On the Instances page, click the target instance name.
  5. In the navigation pane, choose Backups & Restorations.
  6. On the Backups & Restorations page, click Set Backup Policy. If you want to configure a sparse backup policy, click Add Policy. After a sparse backup policy is added, you can modify or delete it.

    Figure 1 Adding a sparse backup policy for a cluster instance of the Community Edition
    • Sparse Backup Policy
      Table 1 Sparse backup policies

      Frequency

      Time

      Local Retention Period

      Weekly

      Select at least one day in a week.

      The retention period specified in a sparse backup policy applies only to the full automated backups associated with this policy. It can be set to 1 to 732 days.

      The retention period for incremental backups is determined by the standard backup policy and is irrelevant to sparse backup policies.

      If you modify the retention period specified in a policy, the modification will be applied to all the existing full automated backups associated with this policy. The retention period specified in any backup policy does not apply to manual backups.
      • Extending the retention period enhances data availability.
      • Reducing the retention period takes effect for existing backups. Any backups (except manual backups) that have expired will be automatically deleted. Exercise caution when performing this operation.

      Monthly

      Select at least one day in a month.

      Every year

      Select a specific day in a year.
    • If multiple sparse backup policies need to create backups on the same day, the system generates only one backup on that day and retains the backup based on the longest retention period.
    • After sparse backup policies are configured, if no backup is generated in the specified backup window of a day (the backup conflicts with other operations or the backup fails), the backup will be skipped.
    • When deleting a sparse backup policy, you can choose whether to retain the backups generated under this policy. If you choose not to keep them, all backups associated with this policy will be deleted immediately. If you choose to keep them, all these backups will be retained for the original retention period.

Parent Topic: Performing Backups