# Updating Entities

{% hint style="warning" %}
**This is the manual for older MicroStream versions (Version < 5.0).**

**The new documentation (Version >= 5.0) is located at:**

[https://docs.microstream.one/](https://docs.microstream.one/manual)
{% endhint %}

The data layer is always immutable. In order to update the values we have to replace the data layer completely. This is done with the updater. The property setter methods can be chained, so it is easy to update multiple properties, for example:

```java
PersonUpdater.New(mike)
			.firstName("Jim")
			.lastName("Hope")
			.update();
```

If only one property needs to be updated, the updater class offers static convenience methods for that:

```java
PersonUpdater.setFirstName(mike, "Jim");
```


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