Query tables in a table hierarchy

A table hierarchy allows you to construct a SELECT, UPDATE, or DELETE statement whose scope is a supertable and its subtables—in a single SQL command. For example, a query against any supertable in a table hierarchy returns data for all columns of the supertable and the columns that subtables inherit from the supertable. To limit the results of a query to one table in the table hierarchy, you must include the ONLY keyword in the query. For more information about how to query and modify data from tables in a table hierarchy, see the HCL OneDB™ Guide to SQL: Tutorial.