CREATE TABLE railway_manage (Railway_ID NUMBER, Manager_ID NUMBER, From_Year CLOB)
CREATE TABLE railway (Railway_ID NUMBER, Railway CLOB, Builder CLOB, Built CLOB, Wheels CLOB, Location CLOB, ObjectNumber CLOB)
CREATE TABLE manager (Manager_ID NUMBER, Name CLOB, Country CLOB, Working_year_starts CLOB, Age NUMBER, Level NUMBER)
CREATE TABLE train (Train_ID NUMBER, Train_Num CLOB, Name CLOB, From CLOB, Arrival CLOB, Railway_ID NUMBER)

A line chart for showing the number of the working years of managers in descending order of their level.
SELECT Working_year_starts, COUNT(Working_year_starts) FROM manager ORDER BY Level DESC
SELECT "Working_year_starts", COUNT("Working_year_starts") FROM "manager" ORDER BY "Level" DESC