A list of names for the columns of the view. If you omit column
    names, SQL assigns the names from the columns in the source
    tables in the select expression.

    However, you must specify names for all the columns of the view
    in the following cases:

    o  The select expression generates columns with duplicate names.

    o  The select expression uses statistical functions or arithmetic
       expressions to create new columns that are not in the source
       tables.