# 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://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(158\).png)

### **Example**

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

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(159\).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://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20(159).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://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/3%20\(29\).png)


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