Default value in a field in the Solr schema can be the current date?

I'm using Solr and I would like to add a field last_u开发者_开发问答pdate in the schema.xml where the default value would be the current date when the document is added or updated.

Do you have an idea how can I do this?

Thanks

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It is a supported scenario for DateField. The following should work:

<field name="last_update" type="date" indexed="true" stored="true" default="NOW" />