# Define parameter value

<figure><img src="/files/SwluzXR5eDnRbMJHSDT7" alt=""><figcaption></figcaption></figure>

The **Define Parameter Value** task allows you to manually assign a new value to an existing parameter within your data flow in **Gaio DataOS**.\
It’s a key feature for **controlling flow execution**, **dynamically updating context**, or **overriding default values** at runtime.

***

## How to Use

### **1. Open the Task**

Navigate to:\
**Tasks > ETL > Define Parameter Value**

***

### **2. Configure the Task Fields**

* **Label:** (Optional) A custom label to identify this task in your flow.
* **Param:** Select the parameter you want to update. It must already exist in the environment.
* **Default:** The parameter’s original default value (read-only).
* **Current:** The current value in use before the update (read-only).
* **Value:** The new value that will be assigned to the parameter during flow execution.

{% hint style="warning" %}
The value defined here will temporarily **override** the current parameter value during the flow run, and can be reused by other tasks in the sequence.
{% endhint %}

***

### **3. Save and Apply**

* After entering the new value in the **Value** field, click **Save**.
* When the flow is executed, the parameter will be updated in real time with the new assigned value.

***

#### Use Cases

* Dynamically update filters or variables before executing queries
* Apply conditional logic based on runtime-defined values
* Customize executions using user input or contextual values
* Override previously inherited parameters from other flows or default settings


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.gaiodataos.com/tools/tasks/etl/define-parameter-value.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.