> For the complete documentation index, see [llms.txt](https://docs.gaiodataos.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.gaiodataos.com/tools/tasks/etl/define-parameter-value.md).

# 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.

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## How to Use

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

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

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### **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 %}

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### **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.

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#### 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