This topic describes how to use OceanBase Migration Service (OMS) Community Edition to migrate data from a Milvus database to OceanBase Database Community Edition.
Background information
Milvus is a high-performance and highly scalable vector database service that provides powerful data modeling features. For more information, see Milvus documentation.
The following table describes the key concepts of Milvus.
Concept |
Description |
|---|---|
| Database | A database is equivalent to a schema. You can create multiple databases in Milvus. A database can contain multiple collections. |
| Collection | A collection is equivalent to a table. It stores detailed data and can contain multiple fields. When you create a collection, you can specify the withEnableDynamicField attribute to allow different records to have different fields. |
| Primary key | A collection contains only one primary key field. |
| Partition | A partition is a division of a collection. A partitioned collection is equivalent to a partitioned table. |
Limitations
At present, OMS Community Edition supports only full data migration from a Milvus database to OceanBase Database Community Edition.
Milvus 2.4.5 and later are supported.
OMS Community Edition does not support the
withEnableDynamicFieldattribute of Milvus. When you create a data migration task, you can use only the fields specified when you created a collection.
Procedure
Create a data migration task.
Log on to the console of OMS Community Edition.
In the left-side navigation pane, click Data Migration.
On the Data Migration page, click Create Migration Task in the upper-right corner.
On the Select Source and Destination page, configure the parameters.
ParameterDescriptionData 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 (Optional) Click the field and select a 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 Milvus 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 a Milvus data source. Destination 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 an OceanBase-CE data source. Click Next. On the Select Migration Type page, select Full Data Migration.
After a full data migration task is started, OMS Community Edition migrates the existing data of tables in the source database to corresponding tables in the destination database.
Click Next. On the Select Migration Objects page, select 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.
When you choose the Specify Objects option, you can select tables only from the
defaultlist. If you want to select other tables, choose the Match Rules option and specify a rule in the form ofdb.*.
OMS Community Edition also allows you to rename objects, set row filters, view column information, and remove a single migration object or all migration objects.
OperationDescriptionRename 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 ofTableName$ColumnFamilyName.Configure settings OMS Community Edition allows you to filter rows by using WHEREconditions. 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.
Click Next. On the Migration Options page, configure the parameters for full migration.
ParameterDescriptionConcurrency Speed Valid values: Stable, Normal, Fast, and Custom. The amount of resources to be consumed by a full data migration task varies based on the migration performance. If you select Custom, you can set Read Concurrency, Write Concurrency, and JVM Memory as needed. Processing Strategy When Records Exist in Target Object Valid values: Ignore and Stop Migration. - If you select Ignore, when the data to be inserted conflicts with the existing data of a destination table, OMS Community Edition retains the existing data and records the conflict data.
Notice
If you select Ignore, data is pulled in IN mode for full verification. In this case, the scenario where the destination contains more data than the source cannot be verified, and the verification efficiency will be decreased.
- If you select Stop Migration and a destination table contains data, an error is returned during full data migration, indicating that the migration is not allowed. In this case, you must clear the data in the destination table before you can continue with the migration.
Notice
After an error is returned, if you click Resume in the dialog box, OMS Community Edition ignores this error and continues to migrate data. Proceed with caution.
Writing Method Valid values: SQL (specifies to write data to tables by using INSERTorREPLACE) and Direct Load (specifies to write data through direct load). For more information about the direct load method, see Direct load.To view or modify parameters of the full migration component Checker-Full, click Configuration Details in the upper-right corner of the Full Migration section. For more information about the parameters, see Component parameters.
- If you select Ignore, when the data to be inserted conflicts with the existing data of a destination table, OMS Community Edition retains the existing data and records the conflict data.
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.
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 is 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.