Oracle PL/SQL Tutorial/System Tables Data Dictionary/all col comments

Find all column comments

SQL>
SQL> SELECT     column_name, comments
  2  FROM       all_col_comments
  3  WHERE      table_name = UPPER("&&table_name");
old   3: WHERE      table_name = UPPER("&&table_name")
new   3: WHERE      table_name = UPPER("")
no rows selected
SQL> UNDEFINE table_name
SQL>