Indexes on views are pretty much the same as with tables with the following exception:

INDEX ON eExpression TO IDXFileName | TAG TagName [OF CDXFileName]
	[FOR lExpression]
	[COMPACT]
	[ASCENDING | DESCENDING]
	[UNIQUE | CANDIDATE]
	[ADDITIVE]

Omitting 'OF CDXFileName' creates a structural index. With a table (Table1.DBF) the CDX is called (Table1.CDX) and is opened automatically when the table is used. With a view, since the only structure is a SQL-Select statement, the the structural index is lost when the view is closed. To maintain a compound index, specify the index name with OF CDXFileName and then when you USE the view - USE View1 INDEX CDXFileName and then immediately REINDEX.

HTH