BEGIN
PROMPT Add a COLUMN with a Default value TO EXAMPLE_TAB
DECLARE
   column_ Database_SYS.ColRec;
BEGIN   
   column_ := Database_SYS.Set_Column_Values('COLS9', 'VARCHAR2(10)', 'N','''My_Default2''');   
   Database_SYS.Alter_Table_Column('EXAMPLE_TAB', 'A', column_, TRUE); 
END;