# Lookup Fields tab

![Avro Input Lookup Fields Tab](/files/2kkOgXYGZoMo2DHWhHca)

You can use the **Lookup Fields** tab to create variables and map them to a specific field to use as lookups into an Avro structure at decoding time. The table in this tab defines the following field properties:

| Field Property    | Description                                                    |
| ----------------- | -------------------------------------------------------------- |
| **Name**          | The name of the incoming field                                 |
| **Variable**      | The variable you want to use as the value of an incoming field |
| **Default value** | The value to use when the incoming field value is null         |

Click **Get fields** to populate the **Name** column with names of the incoming fields.


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