Constraints

Object collection scope

Only database objects related to user services are collected. For details about other objects that are not collected, see section Which Schemas in Source Databases Are Ignored for Migration? in Usage Guide.

Impact on the source database

UGO occupies some database session connections and source database resources during object collection. To prevent UGO from affecting services of the source database, you are advised to export objects from the source database to the test database. UGO can then connect to a test database for collection, evaluation, and conversion. If this type of data collection is necessary, perform it during off-peak hours.

No incremental data migration performed

UGO converts database schemas based on the collected data. Any schema changes after the data is collected will not be migrated. After the migration, the changes must be synchronized between the source and target databases, or, the changed functions will be affected.

Migration and verification

UGO is used to reduce costs and improve migration efficiency. After database objects are migrated, strict tests must be performed to ensure that the functions and performance of the migrated objects on the target database meet service requirements. Otherwise, the target database cannot be used to replace the source database.