Why should the additional OLS row label column be hidden?
Most applications were not designed with access control mechanisms in mind, so Oracle Label Security (OLS) needs to do this transparently. When an application queries a table with a SELECT FROM tablename statement, it returns all columns, including the unhidden label column. Existing applications may not be designed to display an additional column, and malfunction. However, if the label column is hidden, then it is displayed only when it’s name is included in the SQL statement. A SELECT FROM tablename would return all columns as expected by the application, excluding the hidden OLS column.
