# Filter
In this document, you’ll learn how to use the *Filter* transformation in Astera Dataprep to include or exclude records based on a specified condition within your Dataprep Recipe.
Suppose you have a dataset of transactions, but some rows have missing transaction amounts. These incomplete records could lead to incorrect revenue calculations. By applying a filter, you can remove rows where the transaction amount is missing, ensuring that only valid transactions are included in the analysis.
1. To filter in Astera Dataprep, click on the *Transform* option in the toolbar and select *Filter* from the drop-down.
2. Once selected, the *Recipe Configuration – Filter* panel will open.
**Filter Condition:** Here, you can configure the Filter section by entering a condition to include or exclude records.
3. Click on the 
three dots to open *Expression Builder*. Here you can either write your own expression or choose from the built-in functions' library.\
For example, to remove rows where the *Amount* field is missing, you can enter: *Amount IS NOT null*
4. Once done, click 
Apply.
5. Now, in the grid, you can see that only records meeting the specified condition remain in the dataset.
{% hint style="info" %}
**Tip:** You can also ask in Chat to remove rows with missing amounts, and Dataprep will configure the filter for you automatically.
{% endhint %}
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