Skip to main content

OceanBase Oracle Migration Synchronization to StarRocks

NineData data replication supports data synchronization between OceanBase Oracle and StarRocks data sources. It supports structure, full volume, and incremental synchronization.

Prerequisites​

  • The source and target data sources have been added to NineData. For instructions on how to add data sources, see Adding Data Sources.
  • The source database type is OceanBase Oracle.
  • The target data source type is StarRocks.

Usage Limitations​

  • Before executing data synchronization, it is necessary to assess the performance of the source and target data sources, and it is recommended to perform data synchronization during off-peak business hours. Otherwise, the full volume data initialization will occupy a certain amount of read and write resources of the source and target data sources, leading to increased database load.
  • It is necessary to ensure that each table in the synchronization object has a primary key or unique constraint, and the column names are unique; otherwise, the same data may be synchronized repeatedly.

Operation Steps​

Commercialization Notice

NineData’s data replication product has been commercialized. You can still use 10 replication tasks for free, with the following considerations:

  • Among the 10 replication tasks, you can include 1 task, with a specification of Micro.

  • Tasks with a status of do not count towards the 10-task limit. If you have already created 10 replication tasks and want to create more, you can terminate previous replication tasks and then create new ones.

  • When creating replication tasks, you can only select the you have purchased. Specifications that have not been purchased will be grayed out and cannot be selected. If you need to purchase additional specifications, please contact us through the customer service icon at the bottom right of the page.

  1. Log in to the NineData Console.

  2. Click on in the left navigation bar.

  3. On the page, click on in the upper right corner.

  4. On the tab, configure according to the table below and click on .

    Parameter
    		Description
    Enter the name of the data synchronization task. To facilitate subsequent search and management, please use meaningful names as much as possible. Up to 64 characters are supported.
    The data source where the synchronization object is located.
    The data source that receives the synchronization object.
    Choose the case conversion rule for object names when migrating from the source to the target.
    • : Regardless of the naming rules on the source side, the naming rules on the target side are all lowercase.
    • : Follow the naming rules on the source side.
    • : Regardless of the naming rules on the source side, the naming rules on the target side are all uppercase.
    Choose the content that needs to be copied to the target data source.
    • : Only synchronize the database table structure of the source data source, without synchronizing the data.
    • : Synchronize all objects and data of the source data source, that is, full data replication. The switch on the right is the switch for periodic full data replication, more information, please refer to Periodic Full Data Replication.
    • : After the full synchronization is completed, perform incremental synchronization based on the logs of the source data source.
    (required when is selected)
    • : Stop the task when the same name table is detected during the pre-inspection phase.
    • : Send a prompt and continue the task when the same name table is detected during the pre-inspection phase. During structure replication, ignore the table with the same name. If you also perform data replication, the data will be appended to the table with the same name without overwriting the existing data.
    • : Send a prompt and continue the task when the same name table is detected during the pre-inspection phase. During structure replication, delete the table with the same name in the target database and re-copy the table structure based on the source database. If you also perform data replication, the data will be written after the table structure replication is completed.
    • (optional when both structure and data replication are performed): Send a prompt and continue the task when the same name table is detected during the pre-inspection phase. During structure replication, retain the table structure in the target database, and clear the data in the table with the same name at the beginning of data replication, then re-copy from the original table.
    (required when is not selected)
    • : Stop the task when data is detected in the target table during the pre-inspection phase.
    • : Ignore the data when it is detected in the target table during the pre-inspection phase, and append the other data.
    • : Delete the data when it is detected in the target table during the pre-inspection phase, and re-write it.

  5. On the tab, configure the following parameters, and then click on .

    Parameter
    		Description
    Select the content that needs to be copied. You can choose to copy all content from the source database, or you can choose , select the content that needs to be copied in the list, and click > to add it to the right list.

    If you need to create multiple replication links with the same replication object, you can create a configuration file and import it when creating a new task. Click on in the upper right corner, then click on Download Template to download the configuration file template to the local, edit it, and then click on to upload the configuration file to achieve batch import. Configuration file description:

    Parameter
    		Description
    source_table_nameThe source table name where the object to be synchronized is located.
    destination_table_nameThe target table name that receives the synchronized object.
    source_schema_nameThe source Schema name where the object to be synchronized is located.
    destination_schema_nameThe target Schema name that receives the synchronized object.
    source_database_nameThe source database name where the object to be synchronized is located.
    target_database_nameThe target database name that receives the synchronized object.
    column_listThe list of fields that need to be synchronized.
    extra_configurationAdditional configuration information, you can configure the following information here:
    • Field mapping: column_name, destination_column_name
    • Field value: column_value
    • Data filtering: filter_condition
    tip

    • The example content of extra_configuration is as follows:

      {
          "column_name": "created_time", //Specify the original column name for column name mapping
          "destination_column_name": "migrated_time", //Map the target column name to "migrated_time"
          "column_value": "current_timestamp()", //Change the field value of the column to the current timestamp
          "filter_condition": "id != 0" //Only rows with ID not equal to 0 will be synchronized.
      }

    • The overall example content of the configuration file, please refer to the downloaded template.

  6. On the tab, select different operations based on the selected replication type, and then click on . If there are updates in the source and target data sources during the mapping configuration phase, you can click on the button in the upper right corner of the page to refresh the information of the source and target data sources.

    • Including : Configure the table name after the target table is synchronized to the target data source.

    • Not including : The system defaults to selecting the database with the same name in the target data source. If it does not exist, you need to manually select the target database. The table name and column name in the target database need to be consistent with the synchronization object. If they are not consistent, you can also manually map the table name and column name.

    You can click on on the right side of the page to customize the name of the column synchronized to the target data source. In addition, you can also set , and configure the filtering conditions through comparison expressions, only the data that meets the filtering conditions will be synchronized to the target data source. For example, if the filtering condition is set to emp_no>=10005, then the data in the emp_no column with a value less than 10005 will not be synchronized to the target data source.

  7. On the tab, wait for the system to complete the pre-inspection, and after the pre-inspection is passed, click on .

    tip
    • You can check . After the synchronization task is completed, automatically start the data consistency comparison based on the source data source to ensure that the data on both sides is consistent. According to the you selected, the timing of starting is as follows:
      • : Start after the structure replication is completed.
      • +, : Start after the full replication is completed.
    • If the pre-inspection does not pass, you need to click on in the column on the right side of the target inspection item, troubleshoot the cause of the failure, manually repair it, and then click on to re-execute the pre-inspection until it passes.
    • The is for the inspection item, which can be repaired or ignored according to the specific situation.

  8. On the page, it prompts , and the synchronization task starts running. At this time, you can perform the following operations:

    • Click on to view the execution of each stage of the synchronization task.
    • Click on to return to the task list page.

View Synchronization Results​

  1. Log in to the NineData Console.

  2. Click on > in the left navigation bar.

  3. On the page, click on the of the target synchronization task, the page details are as follows.

    result

    Number
    		Function
    		Description
    1Sync DelayThe data synchronization delay between the source data source and the target data source. 0 seconds means there is no delay between the two ends, at which point you can choose to switch the business to the target data source for smooth migration.
    2Configure AlertsAfter configuring alerts, the system will notify you in the way you choose when the task fails. For more information, please refer to Operations Monitoring Introduction.
    3More
    • : Pause the task, only tasks with Running status are selectable.
    • : Create a new replication task with the same configuration as the current task.
    • : End tasks that are unfinished or listening (i.e., in incremental synchronization). Once the task is terminated, it cannot be restarted, so please proceed with caution. If the synchronization objects contain triggers, a trigger replication option will pop up, please select as needed.
    • : Delete the task. Once the task is deleted, it cannot be recovered, so please proceed with caution.
    4Structure Replication (displayed in scenarios involving structure replication)Displays the progress and detailed information of structure replication.
    • Click on on the right side of the page: View the execution logs of structure replication.
    • Click on refresh on the right side of the page: View the latest information.
    • Click on in the column on the right side of the target object in the list: View SQL playback.
    5Full Replication (displayed in scenarios involving full replication)Displays the progress and detailed information of full replication.
    • Click on on the right side of the page: View various monitoring indicators during full replication. During full replication, you can also click on on the right side of the monitoring indicator page to limit the rate of writing to the target data source per second. The unit is rows/second.
    • Click on on the right side of the page: View the execution logs of full replication.
    • Click on refresh on the right side of the page: View the latest information.
    6Incremental Replication (displayed in scenarios involving incremental replication)Displays various monitoring indicators of incremental replication.
    • Click on on the right side of the page: View the operations currently being executed by the current replication task, including:
      • : Replication tasks are executed in multiple threads, displaying the current thread number in progress.
      • : Details of the SQL statement currently being executed by the current thread.
      • : The response time of the current thread. If this value increases, it indicates that the current thread may be stuck for some reason.
      • : The timestamp when the current thread was started.
      • : The status of the current thread.
    • Click on on the right side of the page: Limit the rate of writing to the target data source per second. The unit is rows/second.
    • Click on on the right side of the page: View the execution logs of incremental replication.
    • Click on refresh on the right side of the page: View the latest information.
    7Modify ObjectDisplays the modification records of synchronization objects.
    • Click on on the right side of the page to configure the synchronization objects.
    • Click on refresh on the right side of the page: View the latest information.
    8Data ComparisonDisplays the comparison results between the source data source and the target data source. If you have not enabled data comparison, please click on on the page.
    • Click on on the right side of the page: Re-initiate the comparison between the current source and target data sources.
    • Click on on the right side of the page: After the comparison task starts, you can click this button to stop the comparison task immediately.
    • Click on on the right side of the page: View the execution logs of consistency comparison.
    • Click on (displayed only in data comparison): View the trend chart of RPS (records per second) comparison. Click on to view earlier records.
    • Click on details in the column on the right side of the comparison list (displayed under the tab only in the case of inconsistency): View details of the comparison between the source and target sides.
    • Click on sql in the column on the right side of the comparison list (displayed only in the case of inconsistency): Generate change SQL. You can directly copy this SQL to the target data source to execute and modify the inconsistent content.
    9ExpandDisplay detailed information of the current replication task. Common Options:
    • : Export the current task's database and table configuration, allowing for quick import when creating a new replication task. This helps rapidly establish multiple replication links with the same replication objects.
    • : Configure the alarm strategy for the current task.

Appendix: Pre-Check Item List​

Check ItemCheck Content
Source Data Source Connection CheckCheck the gateway status of the source data source, whether the instance is reachable, and the accuracy of the username and password
Target Data Source Connection CheckCheck the gateway status of the target data source, whether the instance is reachable, and the accuracy of the username and password
Source Library Permission CheckCheck whether the account permissions of the source database meet the requirements

Appendix 2: Data Type Mapping Table​

CategoryOceanBase Oracle Data TypeStarRocks Data Type
Build-in data typeCHAR [(size [BYTE | CHAR])] VARCHAR[(3*size)]
NCHAR[(size)] VARCHAR[(3*size)]
VARCHAR2(size [BYTE | CHAR])VARCHAR[(3*size)]
NVARCHAR2(size) VARCHAR[(3*size)]
CLOB VARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
NUMBER [ (p [, s]) ]
  • NUMBER as an integer:
    • Length < 10: INT
    • Length >= 10 but < 20: BIGINT
    • Length >= 20: LARGEINT
  • NUMBER as a non-integer: DECIMAL
  • NUMBER with IDENTITY auto-increment attribute: LARGEINT
FLOAT [(p)] FLOAT
DATE DATETIME
BINARY_FLOATFLOAT
BINARY_DOUBLE DOUBLE
TIMESTAMP [(fractional_seconds_precision)]DATETIME
TIMESTAMP [(fractional_seconds_precision)] WITH TIME ZONEDATETIME
TIMESTAMP [(fractional_seconds_precision)] WITH LOCAL TIME ZONEDATETIME
INTERVAL YEAR [(year_precision)] TO MONTHVARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
INTERVAL DAY [(day_precision)] TO SECOND [(fractional_seconds_precision)]VARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
RAW(size) VARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
BLOB VARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
REFVARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
VARRAYVARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
NESTED TABLE VARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
Oracle Supplied Data TypeAnyData VARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576
Spatial Data TypeSDO_GEOMETRY VARCHAR[(maxSize)]
maxSize is the maximum length of the VARCHAR type, which varies depending on the version:
  • StarRocks version < 2.1.0: 65533
  • StarRocks version >= 2.1.0: 1048576

Introduction to Data Replication

Last updated on