Name mapping lets you control how DTS names objects in the destination database during a synchronization or migration task. Use it to write data into objects that already exist under different names, or to have DTS create destination objects with names that differ from the source.
Use cases
These use cases also apply when the source and destination are the same database instance and you need data isolation through different database or table names.
| Use case | What to configure |
|---|---|
| Have DTS create the destination object and write data into it | Migration task: Select Schema Migration and at least one of Full Data Migration or Incremental Data Migration. Synchronization task: Incremental Data Synchronization is selected by default; also select Schema Synchronization, and optionally Full Data Synchronization. |
| Write data into an existing object in the destination (for example, merging multiple databases or tables into one) | Create the destination object in advance and confirm data compatibility. Migration task: Do not select Schema Migration. Synchronization task: Do not select Schema Synchronization. |
| Have DTS create the destination object without writing data | Supported for migration tasks only. Select Schema Migration only. |
Prerequisites
Before you begin, ensure that:
The task is at the Configure Objects stage. For steps to reach this stage, see Synchronization solution overview and Migration solution overview.
(Old version) The task is at the Configure Objects and Advanced Settings stage.
Select all options under Migration Types or Synchronization Types. Selecting a subset may produce unexpected results.
Limitations
Do not perform name mapping after the task has started. Doing so may cause data loss or task failure.
If you map an object name, other objects in the source that depend on the mapped object may fail to synchronize or migrate.
If the task selects objects at the entire-database granularity, only database name mapping is supported.
For table or column name mapping, the required granularity depends on the source database type:
Source database type Required granularity MongoDB Collection Tair/Redis Redis DB All other types Table Tair/Redis destinations: Only database name mapping is supported. You can specify the destination as DB 0 through DB 255.
DataHub destinations: Database name mapping is not supported.
Kafka destinations: If you map the Table Name, DTS writes data to the Kafka topic with that name. The topic must already exist in the destination Kafka instance, or the task will fail.
Map individual objects
Move task objects from Source Objects to the Selected Objects area.
Open the mapping dialog for the target object in the Selected Objects area using either method:
Right-click the object.
Hover over the object, then click the Edit button that appears.
Modify the object name in the destination.
Database name mapping: In the Edit Schema dialog, set the destination database name. > Note: When both the source and destination are SQL Server, the Edit Database Name dialog appears instead.
Table name mapping: In the Edit Table dialog, set the destination table name. > Note: For some instances, the Edit Table dialog also lets you add columns and filter DML and DDL statements for incremental tasks. If the database mapping and table mapping specify different statement filters, the table mapping filter takes effect. > > To filter data by condition, configure filter conditions in the Edit Table dialog. For details, see Set filter conditions.
Column name mapping: In the Edit Table dialog, go to the Columns section and set the Destination Column Name for each column. > Note: Column name mapping does not support changing column data types.
Click OK.
Configure other required DTS task parameters.
Batch map objects
Batch mapping applies a naming rule to multiple selected objects at once. You can add a prefix or suffix, replace all names, or shorten names by removing a keyword.
The available rules are the same for all source database types:
| Rule | What it does | Example |
|---|---|---|
| Add Prefix and Suffix | Adds characters before and/or after each name | orders → prod_orders_v2 |
| Change All Names | Replaces all selected names with a single new name | db1, db2 → unified_db |
| Shorten All Names | Removes a specified keyword from each name | prod_orders_archive → prod_orders (keyword: _archive) |
Steps:
Move task objects from Source Objects to the Selected Objects area.
In the upper-right corner of the Selected Objects area, click Batch Edit.
In the Batch Edit dialog, follow the steps for your source database type.
Source database is Tair/Redis
In the Select Objects box, select the objects to edit. The batch edit type defaults to Include Only Selected Databases.
(Optional) In the Select Editing Type area, click the Object Name tab.
Select the effective scope:
Edit Renamed Object Name: Apply the batch rule on top of any previously renamed names.
Edit Original Object Name: Apply the batch rule based on the original source names.
Select a rule and configure it.
Click Apply to add the rule.
Click OK.
Source database is SQL Server
Select the batch edit type. This example uses Select All Databases and Tables.
In the Select Objects box, select the objects to edit.
(Optional) In the Select Editing Type area, click the Object Name tab.
(Optional) Select the object name type:
Library table name: Map only database and table names.
Schema name: Map only schema names.
Select Object Name Type is available only when Schema Mapping Mode of Source and Destination Databases on the Configure Objects page is set to Use \<Source schema name\>.\<Source table name\> as the destination table name, or when that setting does not appear on the page.
Select the effective scope:
Edit Renamed Object Name: Apply the batch rule on top of any previously renamed names.
Edit Original Object Name: Apply the batch rule based on the original source names.
Select a rule and configure it.
Click Apply to add the rule.
Click OK.
Source database is of another type
Select the batch edit type. This example uses Select All Databases and Tables.
In the Select Objects box, select the objects to edit.
(Optional) In the Select Editing Type area, click the Object Name tab.
For some instances, this area also lets you add columns and filter DML and DDL statements for incremental tasks.
Select the effective scope:
Edit Renamed Object Name: Apply the batch rule on top of any previously renamed names.
Edit Original Object Name: Apply the batch rule based on the original source names.
Select a rule and configure it.
Click Apply to add the rule.
Click OK.
After completing the batch mapping, configure other required DTS task parameters.
Synchronize or migrate partial columns
To exclude specific columns from synchronization or migration, clear them in the column list.
Move the table from Source Objects to the Selected Objects area.
Right-click the table in the Selected Objects area to open the table mapping dialog.
In the Edit Table dialog, go to the Columns section and clear the Synchronize All Tables check box.
Clear the check boxes for columns you do not want to synchronize or migrate.
Click OK.
Configure other required DTS task parameters.
FAQ
How do I exclude specific columns from synchronization or migration?
Use column name mapping: in the Edit Table dialog, go to the Columns section, clear the Synchronize All Tables check box, then clear the check boxes for the columns to exclude.
Does column name mapping support changing column data types?
No.
Can I modify a batch edit rule after adding it?
No. To change a rule, click the delete icon 
next to it to remove the rule, then add a new one.
Why did my batch edit rule disappear?
Either you did not click Apply after configuring the rule, or you accidentally deleted it.