> For the complete documentation index, see [llms.txt](https://documentation.astera.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.astera.com/functions/logical/coalesce-any-value1-any-value2.md).

# Coalesce (Any value1, Any value2)

| **Name**    | ***Coalesce***                                                                                        |
| ----------- | ----------------------------------------------------------------------------------------------------- |
| Syntax      | Coalesce (Any value1, Any value2)                                                                     |
| Purpose     | To return first non-null value in order of the parameters specified.                                  |
| Description | Returns the first non-null value from specified parameters. Returns null if both parameters are null. |
| Return Type | Object                                                                                                |
| Parameters  | <p>value1 \[System.Object] – First expression</p><p>value2 \[System.Object] – Second expression</p>   |

![](https://content.gitbook.com/content/zEifS4h8yurLAAwiGNX2/blobs/OTiQRD117c6EyRDse4eA/0.png)

### **Example**

We have a *Customers* dataset, with missing values in the *Items* and *ShipCountry* fields, which we will use for this function.

![](https://content.gitbook.com/content/zEifS4h8yurLAAwiGNX2/blobs/b7J8bUc5lGrXuHWuHfJz/1.png)

We will map these fields to *value1* and *value2* of the function transformation object.

Where,

*value1 = Items*

*value2 = ShipCountry*

Then, we will map the Output *value* field of the function transformation object and the remaining fields from our source file to an *Excel Workbook Destination.*

<figure><img src="https://content.gitbook.com/content/zEifS4h8yurLAAwiGNX2/blobs/HqigiWUoV7ffJNmEXecj/2.png" alt=""><figcaption></figcaption></figure>

Right-click on the *Excel Workbook Destination* object and select *Preview Output.* You can see that Astera Data Stack has created a new column, and returned a value from either *Items* (value1)*, ShipCountry* (value2)*,* or null (if both specified parameters are null), in this particular order.

![](https://content.gitbook.com/content/zEifS4h8yurLAAwiGNX2/blobs/INQPhM7lvK1Ek7Lrimwg/3.png)


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