In most cases, you specify a multi-value property, such as an array or Collection, using the property element, just as you specify a single-value property. In the following example, the features property stores an array of Strings:

<properties>
  <property name="creationDate" type="date"/>
  <property name="brand" is-dimension="true" type="string"
    text-searchable="true"/>
  <property name="displayName" type="string" text-searchable="true"/>
  <property name="features" type="string" text-searchable="true"/>
</properties>

Notice that features is specified in the same way as creationDate, brand, and displayName, which are all single-value properties. The output will include a separate entry for each value in the features array.

If a property is an array or Collection of repository items, you specify it using the item element, and set the is-multi attribute to true. For example, in a product catalog, a product item will typically have a multi-valued childSKUs property whose values are the various SKUs for the product. You might specify the property like this:

<item property-name="childSKUs" is-multi="true">
  <properties>
    <property name="color" is-dimension="true" type="string"
      text-searchable="true"/>
    <property name="description" type="string" text-searchable="true"/>
  </properties>
</item>

If you index by product, the output records will include the color and description value for each of the product’s SKUs.