Indicates whether this instance of QueryDescription represents a query layer or a single table. If true, it is a query layer . Otherwise, it is a single table.
A query layer is an abstraction that is created from one or more database tables and whose construction is specified by an input SQL SELECT statement to the method GetQueryDescription(String,String). A single table, on the other hand, corresponds directly to a standalone table in the database and is constructed by the method GetQueryDescription(String). While these two flavors of QueryDescription objects are more or less similar, there are some key differences in their internal implementations. For example, a Table or FeatureClass representing a query layer is identified by the UniqueQueryLayerName rather than the TableName.