Field projections to select nested fields

Typically the row type is a column, but you can use any row-type expression for field projection. When the row-type expression itself contains other row types, the expression contains nested fields. To access nested fields within an expression or individual fields, use dot notation. To access all the fields of the row type, use an asterisk (*). This section describes both methods of row-type access.

For a discussion of how to use dot notation and asterisk notation with row-type expressions, see the Expression segment in the Informix® Guide to SQL: Syntax.