Database Migration and Verification

Scenarios

After the migration project is created, you need to start the project, select objects to migrate, and configure the conversion solution based on the migration risk items. After syntax conversion is started, UGO converts the SQL syntax of the source database to the syntax compatible with the target database. For syntax that fails to be converted, UGO allows you to correct it. After the modification, migrate objects to the target database in the migration verification phase. You can view the migration progress and details to confirm the migration result.

You can perform the following steps to migrate a database and verify the migration result:

• Step 1: Conversion Configuration
• Step 2: (Optional) Object Selection
• Step 3: Syntax Conversion
• Step 4: Object Migration Verification
• Step 5: Correcting Migration-Failed Objects

Conversion Configuration

1. Log in to the UGO console.
2. In the navigation pane, choose Schema Migration > Object Migration.
3. On the Object Migration page, locate the target project and click Migrate in the Operation column. The Syntax Conversion Configurations page is displayed.
   Figure 1 Setting conversion configuration items
   
   • Set conversion configuration items using either of the following methods:
     • By default, the default template is used. Click Edit in the Operation column of each configuration item to view its details and adjust settings.
     • If maximizing migration success rate is preferred, select Max compatibility from the Baseline Template drop-down list and fine-tune the settings.

4. (Optional) Click the Map Tablespaces tab.

   If you need to add mapping relationships, select a source tablespace and the corresponding target tablespace and click Map Tablespace.

   

   The following migration flows support tablespace mapping.

   • From Oracle to GaussDB
   • From Oracle to PostgreSQL

5. (Optional) Click the Tags tab.

   To add a tag, click Edit Tag. In the displayed Edit Tag dialog box, click Add and enter the key and value.

(Optional) Object Selection

1. Click Next to go to the Convert Syntax page.
2. In the Object List area, select the objects to be converted and migrated. You can search by All time or Object Name, or filter by schema, object status, or converted object.
   Figure 2 Conversion to be started
   
   • Select objects to be converted on the current page.
     • Click Select All or Deselect All to select or deselect all objects.
     • Click the check box before a schema to select specific objects. Click Disable Conversion or Enable Conversion to determine whether the objects will be migrated. Batch operations are supported. You can also filter objects by name or status.
   • To convert only the selected objects, click Convert Selected Objects. On the displayed page, click OK to start object conversion.
   • You may also select objects using conversion policies. For details, see Configuring a Policy.

3. (Optional) Configure GaussDB data distribution.
   • If Object Type is set to TABLE, you can configure data distribution. For details, see Distribution Mapping of Table Objects.

Syntax Conversion

1. In the Conversion area, click Start to start syntax conversion.
   Figure 3 Syntax conversion
   
   • After the conversion is complete, click Conversion Report. On the Conversion Report page, you can view the latest conversion report, download the report, and view the conversion history.

2. After syntax conversion, view the conversion history and details.
   • If you need to modify the conversion plan after the syntax conversion is complete, adjust the conversion settings. For details, see Conversion Configuration.

3. (Optional) If there is any object that failed to be converted, modify the syntax conversion settings for the object and migrate it separately. For details, see Step 4: Migrating Conversion-Failed Objects Separately.

Object Migration Verification

1. Click Next to go to the Verify Migration Results page.
   Figure 4 Migration task
   
   In the Migration Task area, click Configure. The page for configuring migration verification is displayed.

   Figure 5 Configuring migration verification
   
   • Determine whether to migrate objects that failed to be converted.
     • Migrate objects that failed to be converted is deselected by default. If you leave this option unchecked, conversion-failed objects are not included in the migration task.
     • If you select Migrate objects that failed to be converted, conversion-failed objects will be included in the migration task.
   • User connection
     • Set the database connection user to the user executing GaussDB scripts is selected by default. Therefore, the owner of each schema is the database connection user. If this option is checked, the connection user is the owner of each schema.
   • Modify user passwords.
     • If the objects to be converted include USER objects, you must set a unified password. This password is used to create all user objects in the target database. After migration, you must manually update each user's password.

2. Click Start. The system starts migrating objects to the target database.

   Migration success: In the Object List area, the Migration Status column displays Successful. You can log in to the target database to view the migrated objects.

   Migration failure: In the Object List area, the Migration Status column displays Failed. Locate the failed object, click Correct Objects, and modify the object and verify the migration again by referring to Correcting Migration-Failed Objects.

3. After the migration is complete, click Migration Report. The Migration Report page is displayed.
   Figure 6 Migration report
   
   • The Last Migration Report tab page displays detailed information about the most recent migration task, including the object type, total count, migration success count, migration failure count, and remaining objects. If you have configured not to migrate objects that failed to be converted, conversion-failed objects were excluded in the migration verification and the report also shows Objects Not Migrated upon Conversion Failure and Success Rate.
   • The Migration History tab page displays migration history in reverse chronological order, including the serial number, total count, migration success count, migration failure count, migration status, start time, and end time. You can click Details in the Operation column.

4. After all failed objects are corrected and successfully migrated to the target database, the migration task is complete.

Correcting Migration-Failed Objects

1. If there are failed verification items, in the Object List area, modify and migrate them individually or click Batch Update Statements to modify them in batches.
   Figure 7 Migration verification failed
   
   • Select objects to be migrated.
     • Click Select All or Deselect All to select or deselect all objects.
     • Click the check box before a schema to select specific objects. Click Enable Migration or Disable Migration to determine whether the objects will be migrated. Batch operations are supported. You can also filter objects by name or status.
   

   • Select the objects that can be ignored and click Disable Migration. Their Migration Status becomes Ignore. You can also click Enable Migration to revert the status.

2. Click Batch Update Statements to perform batch search and modification for similar issues. For details, see Batch Updating Statements.
3. Correct the syntax for an object that failed to be migrated and then migrate it separately. For details, see Step 5: Migrating Migration-Failed Objects Separately.