Migrate incremental data from OBKV to HBase

This topic describes how to use OceanBase Migration Service (OMS) Community Edition to migrate incremental data from OBKV to an HBase database.

Background information

You can create a data migration task in the console of OMS Community Edition to migrate incremental data from OBKV to an HBase database. For more information about OBKV, see Overview.

Limitations

• Only HBase 1.2.0-cdh5.15.2 and 2.4.13 are supported.

• Only data of a table named in the format of TableName$ColumnFamilyName in OBKV can be migrated by an incremental synchronization task.

• To ensure the performance of a data migration task, we recommend that you migrate no more than 1,000 tables at a time.

Procedure

1. Create a data migration task.

   1. Log on to the console of OMS Community Edition.

   2. In the left-side navigation pane, click Data Migration.

   3. On the Data Migration page, click Create Migration Task in the upper-right corner.

2. On the Select Source and Destination page, configure the parameters.

   Parameter	Description
   Data Migration Task Name	We recommend that you set it to a combination of digits and letters. It must not contain any spaces and cannot exceed 64 characters in length.
   Tag	Click the field and select a target tag from the drop-down list. You can also click Manage Tags to create, modify, and delete tags. For more information, see Use tags to manage data migration tasks.
   Source	If you have created a data source of OceanBase Database Community Edition, select it from the drop-down list. If not, click New Data Source in the drop-down list and create one in the dialog box that appears on the right. For more information about the parameters, see Create a data source of OceanBase Database Community Edition. If the selected source data source has been used as the destination data source of another data migration task, you need to specify whether to filter the data written by OMS Community Edition. If the selected source data source has been used by multiple tasks and you choose to filter the data written by OMS Community Edition, OMS Community Edition obtains the data of the latest migration task by default.
   Destination	If you have created an HBase data source, select it from the drop-down list. If not, click New Data Source in the drop-down list and create one in the dialog box that appears on the right. For more information about the parameters, see Create an HBase data source.
   Scenarios	At present, only Data Migration is supported.

3. Click Next. On the Select Migration Type page, specify the migration type for the migration task.

   At present, only DML Synchronization is supported for Incremental Synchronization. For more information, see DML filtering.

4. Click Next. On the Select Migration Objects page, specify the migration objects and migration scope.

   You can select Specify Objects or Match Rules to specify the migration objects.

   • Select Specify Objects. Then select the objects to be migrated on the left and click > to add them to the list on the right.

     Notice

     • The names of tables to be migrated, as well as the names of columns in the tables, must not contain Chinese characters.

     • If a database or table name contains double dollar signs ($$), you cannot create the migration task.

     OMS Community Edition also allows you to import objects from text, rename objects, set row filters, view column information, and remove a single migration object or all migration objects.

     Operation	Description
     Import objects	In the list on the right of the Specify Migration Scope section, click Import Objects in the upper-right corner. In the dialog box that appears, click OK. Notice This operation will overwrite previous selections. Proceed with caution. In the Import Objects dialog box, import the objects to be migrated. You can import CSV files to rename migration objects and set row filtering conditions. For more information, see Download and import the settings of migration objects. Click Validate. After the validation succeeds, click OK.
     Rename objects	OMS Community Edition allows you to rename migration objects. For more information, see Rename a database table. Note that the new table name must also be in the format of TableName$ColumnFamilyName.
     Configure settings	OMS Community Edition allows you to filter rows by using WHERE conditions. For more information, see Use SQL conditions to filter data. You can also view column information of the migration objects in the View Column section.
     Remove one or all objects	OMS Community Edition allows you to remove a single object or all objects to be migrated to the destination database during data mapping. To remove a single migration object: In the list on the right of the Specify Migration Scope section, move the pointer over the target object, and click Remove. To remove all migration objects: In the list on the right of the Specify Migration Scope section, click Remove All in the upper-right corner. In the dialog box that appears, click OK.

   • Select Match Rules. For more information, see Configure matching rules for migration objects.

5. Click Next. On the Migration Options page, configure the parameters of incremental synchronization.

   Parameter	Description
   Concurrency Speed	Valid values: Stable, Normal, Fast, and Custom. The amount of resources to be consumed by an incremental synchronization task varies based on the synchronization performance. If you select Custom, you can set Read Concurrency, Write Concurrency, and JVM Memory as needed.
   Incremental Synchronization Start Timestamp	Specify a point in time after which data is to be synchronized. The default value is the current system time. For more information, see Set an incremental synchronization timestamp.
   Incremental Record Retention Time	The duration that incremental parsed files are cached in OMS Community Edition. A longer retention period results in more disk space occupied by the Store component of OMS Community Edition.

6. Click Precheck to start a precheck on the data migration task.

   During the precheck, OMS Community Edition checks the read and write privileges of the database users and the network connectivity of the databases. A data migration task can be started only after it passes all check items. If an error is returned during the precheck, you can perform the following operations:

   • Identify and troubleshoot the problem and then perform the precheck again.

   • Click Skip in the Actions column of the failed precheck item. In the dialog box that prompts the consequences of the operation, click OK.

7. Click Start Task. If you do not need to start the task now, click Save to go to the details page of the data migration task. You can start the task later as needed.

   OMS Community Edition allows you to modify the migration objects when the data migration task is running. For more information, see View and modify migration objects. After the data migration task is started, it will be executed based on the selected migration types. For more information, see the "View migration details" section in the View details of a data migration task topic.