---
title: "Union Schedules"
slug: "union-schedules"
tags: ["union", "schedule", "data"]
updated: 2022-12-28T15:57:28Z
published: 2022-12-28T15:57:28Z
canonical: "documentation.decisions.com/union-schedules"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://documentation.decisions.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Union Schedules

| ## Step Details |
| --- |
| **Introduced in Version** | 4.0.0 |
| **Last Modified in Version** | 5.0.0 |
| **Location** | Designer Entities > Scheduling |

The **Union Schedules** step combines schedule data and returns a list of all schedule data.

---

## Properties

#### Inputs

| Property | Description | Data Type |
| --- | --- | --- |
| Folder Ids | Folder Ids | List of String |
| From Date | Starting Date | DateTime |
| To Date | Ending Date | DateTime |

#### Outputs

| Property | Description | Data Type |
| --- | --- | --- |
| Output | List of scheduled data | List of Calculation Result |

---

## Common Errors

### Parameter 'toDate' of 'IntersectSchedules' can not be null

If date fields are not configured or entered correctly, an error will occur. To correct this, ensure that the Date fields are mapped or entered correctly.

#### Exception Message:

```csharp
Exception Stack Trace: DecisionsFramework.BusinessRuleException: [BusinessRule] Parameter 'toDate' of 'IntersectSchedules' can not be null 
at DecisionsFramework.Design.Flow.CoreSteps.InvokeMethodUtility.ThrowErrorIfNullIsNotAllowed(MethodInfo methodInfo, Object[] parameterValues, String errorMessage
 at DecisionsFramework.Design.Flow.StepImplementations.InvokeMethodStep.Run(StepStartData data
 at DecisionsFramework.Design.Flow.FlowStep.RunStepInternal(String flowTrackingID, String stepTrackingID, KeyValuePairDataStructure[] stepRunDataValues, AbstractFlowTrackingData trackingData
 at DecisionsFramework.Design.Flow.FlowStep.Start(String flowTrackingID, String stepTrackingID, FlowStateData data, AbstractFlowTrackingData trackingData, RunningStepData currentStepData)
```

## Related

- [Compute Schedule](/compute-schedule.md)
- [Intersect Schedule](/intersect-schedule.md)
- [Check Schedule](/check-schedule.md)
- [Find Prior Day in Schedule](/find-prior-day-in-schedule.md)