This topic describes how to view and modify parameters of a data validation task in OceanBase Migration Service (OMS).
Limitations
OMS allows you to modify the validation parameters of a data validation task in the Not Started, Stopped, or Failed state.
View parameters
Log in to the OMS console.
In the left-side navigation pane, click Data Validation.
On the Data Validation page, click the ... next to the target task and then click View Parameters.
You can also click the task name to go to the task details page, and then click ... in the upper-right corner and select View Parameters.
On the View Parameters page, view the configurations of the current task.
Modify parameters
Log in to the O&M console.
In the left-side navigation pane, click Data Validation.
On the Data Validation page, click the ... icon next to the target task and select Modify Parameters.
You can also click the name of the target task to go to the details page of the task, click the ... icon in the upper-right corner and select Modify Parameters.
On the panel that appears, modify the parameters as needed.
Full validation
If you create a data validation task, you must select Full Validation in the Select Type & Objects step for the following parameters to be displayed.
Parameter Description Source Concurrency/Target Concurrency The minimum value is 1, and the maximum value is 512. The default value is 4. Validation Mode The following two modes are supported: Adaptive Mode or IN Mode. - Adaptive Mode: data is obtained in batches from the source and target, and the data is compared precisely.
- IN Mode: data is obtained in batches from the source. Data is queried in the target based on the unique key of the target data. Data consistency is verified between the two ends. Note that this mode cannot verify data that exists in the target but not in the source. The validation performance is also degraded. We recommend that you use this mode only when the target has redundant data that is expected and does not require validation, or when the migration scenario involves multi-table aggregation.
Limit BPS The unit is MiB/s, and the maximum value is 1024. If you enable this option, you must configure at least one minimum rate for the source or target. Hidden Column Based Validation During data migration, hidden columns are added and unique keys are created for tables without non-null unique keys in the target to ensure data consistency. Data migration can verify data based on the unique key. For more information, see Hidden column mechanism of data migration service.
This parameter is displayed only when the data migration is OB_MySQL to OB_MySQL, OB_Oracle to OB_Oracle/Oracle, or Oracle to OB_MySQL/OB_Oracle.Row validation
If you create a data validation task, you must select Row Count Validation in the Select Type & Objects step for the following parameters to be displayed.
Parameter Description Concurrent Tables for Validation The minimum value is 1, and the maximum value is 100. The default value is 10. This configuration applies to both the source and the target. Query Timeout The unit is minutes, the minimum value is 1, and the maximum value is 1440. The default value is 10. This configuration applies to both the source and the target. Incremental validation
If you create a data validation task, you must select Incremental Validation in the Select Type & Objects step for the following parameters to be displayed.
Parameter Description Validation Start Point The start timestamp for incremental validation. By default, the task start time is used. Only incremental changes after the incremental validation start time are verified. Validation End Point The end timestamp for incremental validation. You can set any time after the start time. When incremental change validation for the source and target reaches the specified timestamp, validation is completed. Initial Check Configuration Data is verified based on incremental changes in the source and target. If initial validation finds inconsistent data, validation is re-initiated. Initial check configuration includes: - Hot Data Cooldown Period: specifies the time to wait for the last change to be verified when the same data is frequently changed in the source. The unit is seconds, with a minimum value of 1 and a maximum value of 3600. The default value is 5.
- Mismatch Detection Delay: specifies the time to wait for the data to be verified again after incremental data in the source and target is inconsistent. If the data is still inconsistent, inconsistent data is reported.
The unit is seconds, with a minimum value of 1 and a maximum value of 86400. The default value is 30.
Recheck Configuration If initial validation finds inconsistent data, validation is re-initiated. The latest data is obtained from the source and target databases for comparison. If the data is still inconsistent after repeated validation, the validation task is completed, and inconsistent data is reported. Recheck configuration includes: - Recheck Concurrency: specifies the maximum number of concurrent data queries to the source and target for recheck. The minimum value is 1, and the maximum value is 512. The default value is 16.
- Recheck Timeout: specifies the maximum time for recheck. If the data is still inconsistent after the specified time, the validation task is completed, and inconsistent data is reported. The unit is minutes, with a minimum value of 1 and a maximum value of 720. The default value is 30.
- Limit BPS: specifies the maximum traffic for data queries to the source and target in MiB/s. The maximum value is 1024.
Hidden Column Based Validation Specifies whether to verify data based on hidden columns. To ensure data consistency during data migration, hidden columns and unique keys are added to tables in the target without non-null unique keys. Data migration can use this unique key to perform incremental validation. For more information, see Hidden column mechanism of data migration service.
This parameter is displayed only when the data migration is OB_MySQL to OB_MySQL, OB_Oracle to OB_Oracle/Oracle, or Oracle to OB_MySQL/OB_Oracle.
Click Save.