Processing Data

DRS processes synchronized objects and allows you to add rules for selected objects.

Filtering Data

After a data filtering rule is added, update the source database to ensure data consistency. For example:

  • The filter criteria are met after the update. You need to continue the synchronization and perform the same update operation on the destination database. If no data is matched, the operation will be ignored, causing data inconsistency.

  • The filter criteria are not met after the update. You need to continue the synchronization and perform the same update operation on the destination database.

  1. In the Object area of the Data filtering page, select the table to be processed.

  2. In the Filtering Criteria area, enter the filter criteria (only the part after WHERE in the SQL statement, for example, id=1), and click Verify.

    Note

    • Each table has only one verification rule.

    • Up to 500 tables can be filtered at a time.

    • The filter expression cannot use the package, function, variable, or constant of a specific DB engine. It must comply with the general SQL standard. Enter the part following WHERE in the SQL statement (excluding WHERE and semicolons), for example, sid > 3 and sname like "G %". A maximum of 512 characters are allowed.

    • In SQL statements for setting filter criteria, keywords must be enclosed in backquotes, and the value of datatime (including date and time) must be enclosed in single quotation marks, for example, `update` > '2022-07-13 00:00:00' and age >10.

    • Filter criteria cannot be configured for large objects, such as CLOB, BLOB, and BYTEA.

    • You are not advised to set filter criteria for fields of approximate numeric types, such as FLOAT, DECIMAL, and DOUBLE.

    • Do not use fields containing special characters as a filter condition.

    • You are not advised to use non-idempotent expressions or functions as data processing conditions, such as SYSTIMESTAMP and SYSDATE, because the returned result may be different each time the function is called.

  3. After the verification is successful, click Generate Processing Rule. The rule is displayed.

  4. Click Next.

Viewing Data Filtering Results

  1. In the task list, click the task to be processed.

  2. Click the Process Data tab to view data filtering records. Click image1 in the upper right corner to refresh the record list.