Help Center/ Data Replication Service/ Real-Time Synchronization/ Operation Reference in Synchronization Scenarios/ Forcibly Stopping Synchronization of GaussDB Distributed
Updated on 2024-03-28 GMT+08:00
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Forcibly Stopping Synchronization of GaussDB Distributed

This section describes how to clear the streaming replication slots of the source GaussDB distributed database after the incremental or full+incremental synchronization task is forcibly stopped.

The naming rule of a replication slot depends on the database kernel version (you can run the select working_version_num(); command to view the version). If the version is earlier than 92556, serial decoding is used by default. The naming rule of a replication slot is replication_slot_unique_ID. If the version is 92556 or later, parallel decoding is used by default. The naming rule of a replication slot is drs_unique_ID. To obtain the unique ID, replace the hyphen (-) in the task node ID with an underscore (_). You can find the node ID in the task node id is *** log on the Synchronization Logs page.

Prerequisites

Common users do not have the permission to perform the execute direct operation. To delete streaming replication slots, contact GaussDB O&M personnel.

Procedure

  1. Log in to each primary DN node of the GaussDB distributed instance as the user used when you tested the connectivity between the DRS instance and the GaussDB distributed instance.
  2. Run the following statement to query the streaming replication slot name of the database object selected for the synchronization task: 

    select slot_name from pg_replication_slots where database = 'database';

    In the preceding command, database indicates the database selected in the synchronization task.

  3. Run the following statement to delete the streaming replication slot: 

    select * from pg_drop_replication_slot('slot_name');

    In the preceding command, slot_name indicates the name of the streaming replication slot queried in 2.

  4. Run the following statement to check whether the streaming replication slot is successfully deleted: 

    select slot_name from pg_replication_slots where database = 'database';

    If the query result is empty, the streaming replication slot is deleted.

  5. Repeat the preceding operations to ensure that the streaming replication slot on each primary DN is deleted.