> For the complete documentation index, see [llms.txt](https://docs.verbdata.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verbdata.com/data-transformations/building-transformations/transformation-steps/window-data.md).

# Window Data

Creates a column within the selected table which aggregates values based on the selected aggregation type, partition column and sorting column(s).

The aggregation functions are Minimum, Maximum, Average, Median, and Sum.

Data is initially partitioned based on selected column(s). Partitioning data arranges all similar values together within the table.

Values are then arranged within the partition and sorted based on secondary “order by” column(s).

The aggregation function is then performed on resulting sorted data within the selected input column.

The resulting created column is the ranked/sorted data with the values aggregated within each row as selected.

{% hint style="info" %}
Typical aggregation functions result in multiple rows outputting one value. 

Window Data aggregates within each row, resulting in aggregated values for each row.
{% endhint %}

Window Data also includes the Count function. This is the same as the Rank Data Row Number, which outputs a unique sequential value based on the partitioned column values. Rows with equal values will be ranked sequentially, and values will be counted by final row order (ascending/descending) and will not have ties.


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