Examine the following command:

多项选择题 Examine the following command: CREATE TABLE (prod_id number(4), Prod_name varchar2 (20), Category_id number(30), Quantity_on_hand number (3) INVISIBLE); Which three statements are true about using an invisible column in the PRODUCTS table?（）: A、The %ROWTYPE attribute declarations in PL/SQL to access a row will not display the invisible column in the output.; B、The DESCRIBE commands in SQL *Plus will not display the invisible column in the output.; C、Referential integrity constraint cannot be set on the invisible column.; D、The invisible column cannot be made visible and can only be marked as unused.; E、A primary key constraint can be added on the invisible column.

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