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# Configuring Unit of Work Conforming at the Descriptor Level

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Conforming is a query feature that lets you include new, changed, or deleted objects in queries within a unit of work prior to committing the transaction. This feature enables you to query against your relative logical or transaction view of a data source.

Table: Descriptor Support for Unit of Work Conforming summarizes which descriptors support descriptor level unit of work conforming.

Descriptor Support for Unit of Work Conforming

Descriptor | Using TopLink Workbench | Using Java
--- | --- | ---
Relational DescriptorsFoot 1 |  |
Object-Relational Descriptors |  |
EIS DescriptorsFoot 2 |  |
XML Descriptors |  |

Footnote 1 Relational class descriptors only (see "Relational Class Descriptors").

Footnote 2 EIS root descriptors only (see "EIS Root Descriptors")

When you configure a descriptor to conform results in a unit of work, when you execute a query in the unit of work, TopLink filters the data source result set to the changes currently made in the unit of work. TopLink adds new or changed objects that correspond to the query's selection criteria and removes changed objects that no longer correspond to the query's selection criteria.

Note: For EIS root descriptors, only deleted objects would be filtered, not new or changed objects.

Conforming can reduce performance. Before you enable a descriptor for conforming, be aware of its limitations (see "Guidelines for Using Conforming") and make sure that conforming is actually necessary.

For examples, see the following:

- "Using Conforming Queries and Descriptors"

- "Conforming Query Alternatives"