Can the defaultSearchField in a Solr schema be set to "any or all" fields?

There is a parameter in the Solr schema to set a default search field like so...

<!-- field for the QueryParser to use when an explicit fieldname is absent -->
<defaultSearchField>detail</defaultSearchField开发者_如何转开发>

...But I would like to search all fields (I have five besides "detail") when the user does not specify.

How can I make search all fields the default behavior?

---

Use "copy field" instructions to copy the content of all fields into a "catch all" field at index time. Use that field as the default search field.