---
category: [Administration & Integrations/Custom Integrations & Apps, Administration & Integrations, Platform and Product Extensions/Workday Extend, Platform and Product Extensions, Platform and Product Extensions/Integration]
keyword: [Extend, Model Components, Extend Business Objects, MCBO, Model Component Business Objects, Business Objects, Model BO]
nav: wcp_docs
parent_url: /wcp_docs/
title: >- 
  Concept: Restrictions on Target Workday Business Objects
layout: subsection
---

When you create a relationship from a Workday Extend business object to a target Workday business object, restrictions on the target Workday business object might affect the behavior of your Extend app.

## <a id="section_s5j_wpb_w5b"></a>Deleting Tenanted Instances

You can't delete tenanted instances of these Workday business objects if an instance of an Extend business object in your app references the tenanted instance as a target in a `SINGLE_INSTANCE` field.

-   Customer Contract Line
-   Customer Invoice Line
-   Employee Review Template
-   Journal Line
-   Payroll Input
-   Payroll Off-Cycle Result Override
-   Project Plan Task


To delete the tenanted instance, remove the relationship between the instance of the Extend business object and the instance of the target Workday business object.

## <a id="section_h3s_fg2_w5b"></a>Purging Data from Tenanted Instances

You can purge data from tenanted instances of these Workday business objects:

-   Candidate
-   Goal
-   Job Application
-   Payroll Input
-   Payroll Off-Cycle Result Override
-   Supplier
-   Worker Document


If an instance of an Extend business object in your app references the tenanted instance as a target in a `SINGLE_INSTANCE` field, purged instance data will no longer display in reports on the Extend business object.

For more information, see [The Next Level: Data Purging](https://community.workday.com/node/720485) on Workday Community.

## <a id="section_aks_dmj_w5b"></a>Merging Duplicate Person Records

Workday provides a Duplicate Management framework that enables customers to view and merge duplicate person records. You can merge data from these business objects:

-   Applicant
-   Candidate
-   Job Application
-   Student
-   Student Application


Example: A person fills out a job application and later becomes a candidate for the job. Each record represents the same person, but might contain different data. Merging this data results in a single person record in Workday.

If your Extend business object references the source Workday business objects (Job Application or Candidate), any changes made to the person record after these business objects are merged won't be reflected in the instance data of the Extend business object. This might cause your Extend app to be out of synch with current Workday data.

For more information, see [Merge Duplicate Candidates](https://community.workday.com/node/862347) on Workday Community.

### Related Information

[Reference: Targets for Referencing Workday Business Objects](/wcp_docs/qwm1559767719386.html)