# Datetime

Datetime columns indicate a point of time. This can be at any granularity: to the nearest day, minute, second or even nanosecond. Typically, the datetime will be represented as a string.

![For example, you might be storing the last day users have logged into your site.](/files/VwnJpSeHbGDkXbCvJYRL)

{% hint style="warning" %}
Always double check to see if the datetime columns are being detected. A datetime column might be incorrectly detected as categorical if it's in a non-standard format.
{% endhint %}

## General Datetime Transformers

These transformers encode your datetime data as numerical values, ready for data science and machine learning.

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><a href="/pages/hdOiUNS4w7CkPdefbT61"><strong>UnixTimestampEncoder</strong></a></td><td>Encode datetimes as numerical values based on the Unix timestamp.</td><td><a href="/pages/hdOiUNS4w7CkPdefbT61">/pages/hdOiUNS4w7CkPdefbT61</a></td></tr><tr><td><a href="/pages/oYjzqAAUwxxu64pKz8be"><strong>OptimizedTimestamp Encoder</strong></a></td><td>Encode datetimes as numerical values using the least common denominator.</td><td><a href="/pages/oYjzqAAUwxxu64pKz8be">/pages/oYjzqAAUwxxu64pKz8be</a></td></tr></tbody></table>

## Differential Privacy Transformers

These transformers use differential privacy techniques to add noise or reshape your column of datetime data. As a result, your column — and any statistics about it — can be shared with differential privacy guarantees.

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td>❖ <a href="/pages/extox9S27kWUOZbZKoxp"><strong>DPTimestampLaplaceNoiser</strong></a></td><td>Privatize the data by adding Laplacian noise</td><td><a href="/pages/extox9S27kWUOZbZKoxp">/pages/extox9S27kWUOZbZKoxp</a></td></tr></tbody></table>

{% hint style="info" %}
❖ **SDV Enterprise Bundle**. This feature is available as part of the **Differential Privacy Bundle**, an optional add-on to SDV Enterprise. For more information, please visit the [Differential Privacy Bundle](https://docs.sdv.dev/sdv/reference/explore-sdv/differential-privacy-bundle) page. *Coming soon!*
{% endhint %}


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