BEGIN
PROMPT Add a NOT NULL COLUMN TO EXAMPLE_TAB
DECLARE   
   column_ Database_SYS.ColRec;
BEGIN   
   column_ := Database_SYS.Set_Column_Values('COLS8', 'VARCHAR2(10)', 'N','''My_Default''',keep_default_ => 'N');   
   Database_SYS.Alter_Table_Column('EXAMPLE_TAB', 'A', column_, TRUE);
END;