> For the complete documentation index, see [llms.txt](https://docs-v3.toucantoco.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs-v3.toucantoco.com/data-management-in-datahub/datasets-in-toucan/preparing-data/overview-of-youprep-tm/filter/keep-columns.md).
# Keep columns
The Keep columns step allows you to choose a column or multiple columns, meaning that it will delete every other columns. Useful when you have a lot of columns and that you only need to use a few of them.
### Step parameters
* `Keep columns` **(array)\***: specify one or several column(s) to keep
### Example
**Input**
---
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