---
category: [Administration & Integrations, Platform and Product Extensions, Platform and Product Extensions/Integration, Administration & Integrations/Custom Integrations & Apps]
keyword: [Extend, Workday Query Language, WQL]
nav: wcp_docs
parent_url: /wcp_docs/
title: >- 
  Concept: Related Business Objects in WQL
layout: subsection
---

You can access fields from a related business object (RBO) in the `SELECT` clause using curly bracket `{}` notation.

You can also filter query results by RBO fields using the `WHERE ON` clause. In `WHERE ON` clauses, omit the curly bracket `{}` notation for the RBO fields.

The responses from these endpoints now return the related business object for each field:

-   `GET /dataSources/{ID}/fields`
-   `GET /dataSources/{ID}/dataSourceFilters/{subresourceID}`


## <a id="d393e372"></a>Syntax

```
SELECTfield1{relatedBusinessObjectField1, relatedBusinessObjectField2} FROMdataSource
```

Example: `SELECT dependents{age} FROM allWorkers`

You can reference a single field or multiple, comma-separated fields from an RBO field.

You can also assign a custom alias to an RBO field. Example: `dependents{age} as DependentsAge`

## <a id="d393e405"></a>Examples

Return the worker and multiple fields from the <b>Dependents</b> RBO in 1 group:

```
SELECT worker, dependents{legalName_FirstName, legalName_LastName, age}
FROM allWorkers
```

Return the worker and multiple fields from the <b>Dependents</b> RBO as separate groups:

```
SELECT worker, dependents{legalName_FirstName} as FirstName, dependents{legalName_LastName} as LastName, dependents{age} as Age
FROM allWorkers
```

When you call multiple fields separately from the same lookup field, use a unique field alias.

## <a id="d393e433"></a>Limitations

When the lookup field for the RBO is multi-instance, Workday only supports up to 500 values for the RBO field. Example: You specify a worker as a primary business object and worker dependents as the RBO. When the query returns more than 500 dependents for a worker, WQL displays an error. Consider using a data source that is based on a Dependents data source instead.

You can’t access fields from RBOs:

-   In queries that use a `GROUP BY` clause.
-   Outside of the `SELECT` and `WHERE ON` clauses.



When you use a third-party API client, you might need to encode the query first. Some third-party clients don't process curly bracket `{}` notation.

Example query before encoding:

```
SELECT worker, dependents{legalName_FirstName} as FirstName FROM allWorkers
```

Example query after encoding:

```
SELECT%20worker%2C%20dependents%7BlegalName_FirstName%7D%20as%20FirstName%20FROM%20allWorkers
```

### Related Information

[Administrator Guide: Concept: Business Objects, Data Sources, and Fields](https://doc.workday.com/access/sources/dita/topic?wd:docset=adminguide&ft:locale=en-US&resourceid=dan1370796449300)