How to search across multiple fields in Lucene using Query Syntax?

Based on the answers I got for this question: Impact of repeat value across multiple fields in Lucene...

I can put the same search term into multiple fields and therefore create an "all" field which I put everything in. This way I can create a query like...

field1:"hello" AND all:"world"

This seems to work very nicely, prevents the need for huge search queries, and apparently the performance impact is minimal.

Boolean (OR) queries with a clause for each field are used to search multiple fields. The MultiFieldQueryParser will do that as well, but the fields still need to be enumerated. There's no implicit "all" fields; but IndexReader.getFieldNames can acquire them.