loading..
Русский    English
10:07

Ships

The database of naval ships that took part in World War II is under consideration.

Схема данных Корабли

The database has the following relations:

  1. Classes (class, type, country, numGuns, bore, displacement)
  2. Ships (name, class, launched)
  3. Battles (name, date)
  4. Outcomes (ship, battle, result)

Ships in classes are arranged to a single project. A class is normally assigned the name of the first ship in the class under consideration (head ship); otherwise, the class name does not coincide with any ship name in the database.

The Classes relation includes the class name, type (bb for a battle ship, or bc for a battle cruiser), country where the ship was built, number of main guns, gun caliber (diameter of the gun barrel, in inches), and displacement (weight in tons).

The Ships relation includes the ship name, its class name, and launch year.

The Battles relation covers the name and date of a battle the ships participated; while the result of their participation in the battle (sunk, damaged, or unharmed - OK) is in the Outcomes relation.

Notes:

1) Outcomes relation may include the ships not included in the Ships relation. 2) Sunk ship can not participate in battles after that.

Read in more detail...

Tags
aggregate functions Airport ALL AND AS keyword ASCII AVG Battles Bezhaev Bismarck C.J.Date calculated columns Cartesian product CASE cast CHAR CHARINDEX Chebykin check constraint classes COALESCE common table expressions comparison predicates Computer firm CONSTRAINT CONVERT correlated subqueries COUNT CROSS APPLY CTE data type conversion data types database schema DATEADD DATEDIFF DATENAME DATEPART DATETIME date_time functions DDL DEFAULT DEFAULT VALUES DELETE DISTINCT DML duplicates edge equi-join EXCEPT exercise (-2) More tags
The book was updated
several days ago
©SQL-EX,2008 [Evolution] [Feedback] [About] [Links] [Team]
All right reserved.