Legacy Virtual Keys
- Last Updated: July 30, 2025
- 1 minute read
- DataDirect Connectors
- ODBC
- MongoDB 8.0
- Documentation
Attribute
LegacyVirtualKeys (lvk)
Purpose
Specifies whether the driver generates legacy virtual keys for newly-discovered nested objects when mapping the relational view of data.
For versions earlier than 8.1, the driver used the naming convention object_name_GENERATED_ID for the unique virtual key column, which was used as a foreign key to associate the child table back to the parent table. Starting in version 8.1, the driver uses the POSITION column for this purpose.
By default (LegacyVirtualKeys=0), normalized schemas migrated from the 8.0 format retain the legacy key column for existing objects, while the driver generates POSITION columns for newly-discovered nested objects. To use a consistent naming convention for virtual key columns in migrated schemas, set this option to 1.
Valid Values
0 | 1
Behavior
If set to 1 (true), the driver generates legacy virtual keys and POSITION columns when mapping newly-discovered nested objects for both new and migrated schemas. Virtual keys are populated in the object_name_GENERATED_ID column.
If set to 0 (false), the driver uses the POSITION column when mapping newly-discovered objects for both new and migrated schemas. Note that migrated schemas will continue to use the object_name_GENERATED_ID column for existing objects, but newly-discovered objects will have only the POSTION column.
Default Value
0 (false)