Develop A Database With Geographic And Other Information ✓ Solved

Develop A Database With Geographic And Other Information Ab

Develop a database with geographic and other information about the countries of the world. As a first step you need to design an ER diagram that captures relevant information about the countries of the world.

A country has a number of attributes, including a name, area, population, and GDP. A country has also a capital city, which itself has a name, population, and geographical coordinates (latitude, longitude). With each country there can be several spoken languages and several predominant religions.

Countries are located on continents, the latter having a name and area. Any two countries may have a border between them of a particular length. A city can be part of a country, and can also be situated on an island, or at a lake, river, or sea.

A lake has a name, area, maximal depth, and altitude; a river has a name, length, and can flow in or out of a lake, or into a sea; a sea has a name, (maximal) depth, and may be connected with another sea. An island has a name, area, and may be part of one or more countries.

Here are the specific tasks you have to address based on the above information:

(a) Design a conceptual database schema (i.e., an Entity-Relationship diagram) for the above scenario based on the given information. Be sure to indicate primary key attributes for each entity type! Also, indicate derived (computed, not stored) attributes, if any. For each relationship type, clearly specify the semantics of a relationship type using the (min,max) notation presented in class. Note that an edge without a (min,max) specification is assumed to have the default specification (0,∗).

(b) Identify (reasonable) constraints that you are unable to capture using the standard ER modeling constructs. Do not specify trivial domain constraints, e.g., “attribute X is a positive number.” Formulate these constraints in plain English. For each constraint, give a brief explanation why you need the constraint and why you cannot express it in the ER diagram, e.g., using cardinalities.

(c) Translate your ER schema into a relational schema: For each table, list all attributes. To specify the tables, use the following notation, i.e., tablenamei (attribute1i, . . . , attributeni) ... Plus the notation for foreign key constraints (where needed). You do not have to specify any integrity constraints other than foreign key constraints, nor the attribute domains for the tables.

Paper For Above Instructions

The development of a database to encapsulate geographic and other essential information about the countries of the world requires careful planning and a well-structured approach. To effectively represent the various entities and relationships, we will design an Entity-Relationship (ER) diagram. This diagram will include vital attributes relating to countries, cities, geographical features, and interpersonal relations between these entities.

1. Entity-Relationship Diagram Design

The following entities will be included in the ER diagram:

  • Country (CountryID, Name, Area, Population, GDP)
  • City (CityID, Name, Population, Latitude, Longitude, CountryID)
  • Continent (ContinentID, Name, Area)
  • Language (LanguageID, Name)
  • Religion (ReligionID, Name)
  • Lake (LakeID, Name, Area, MaxDepth, Altitude)
  • River (RiverID, Name, Length, LakeID)
  • Sea (SeaID, Name, MaxDepth)
  • Island (IslandID, Name, Area)

Relationships

  • Country-Capital City: A country has one capital city. (1,1)
  • Country-Language: A country can have multiple languages. (0,*) (Many-to-Many)
  • Country-Religion: A country can have multiple religions. (0,*) (Many-to-Many)
  • Country-Continent: A country belongs to one continent. (1,1)
  • Country-Border: Two countries can share a border, which has a particular length. (0,2)
  • City-Island: A city could be located on one or more islands. (0,*) (Many-to-Many)
  • City-Lake: A city could be located near or on a lake. (0,1)
  • City-River: A city could be located near or on a river. (0,1)
  • Sea-Connected Sea: One sea may be connected to another sea. (0,*) (Many-to-Many)

2. Constraints Beyond ER Modeling

There are certain constraints that cannot be expressed through the standard ER diagram constructs. These include:

  • Languages Spoken: In a country, the official language must be one of the spoken languages, but it cannot be enforced through the ER model without additional rules. This hierarchy is crucial for maintaining linguistic representation at the national level.
  • Border Length Limitations: While borders can be defined between two countries, there may be limitations on the maximum allowable length to prevent conflicts in smaller nations. This cannot be represented without custom checks in the database logic.
  • Religious Predominance: A country may list multiple religions, but it must be possible to indicate which religion is predominant; this aspect requires specific note that cannot be captured within a standard ER diagram.

3. Translating the ER Schema into a Relational Schema

Once the ER diagram is established, the next step is to translate that schema into a relational database. The representation of tables and relationships is essential for seamless database operation.

  • Countries (CountryID, Name, Area, Population, GDP, ContinentID)
  • Cities (CityID, Name, Population, Latitude, Longitude, CountryID)
  • Continents (ContinentID, Name, Area)
  • Languages (LanguageID, Name)
  • Countries_Languages (CountryID, LanguageID) - Foreign Key: CountryID references Countries, LanguageID references Languages
  • Religions (ReligionID, Name)
  • Countries_Religions (CountryID, ReligionID) - Foreign Key: CountryID references Countries, ReligionID references Religions
  • Lakes (LakeID, Name, Area, MaxDepth, Altitude)
  • Rivers (RiverID, Name, Length, LakeID) - Foreign Key: LakeID references Lakes
  • Seas (SeaID, Name, MaxDepth)
  • Islands (IslandID, Name, Area)
  • Cities_Islands (CityID, IslandID) - Foreign Key: CityID references Cities, IslandID references Islands

Conclusion

The design and implementation of a database containing geographic and demographic information about countries require a structured outline, which has been provided through the ER diagram and relational schema detailed above. Identifying crucial relationships and formulating additional constraints will enable the database to function effectively and fulfill its purpose.

References

  • Elmasri, R., & Navathe, S. B. (2016). Fundamentals of Database Systems. Pearson.
  • Harrington, J. L. (2016). Relational Database Design and Implementation. Morgan Kaufmann.
  • Chen, P. P. (1976). The Entity-Relationship Model—Toward a Unified View of Data. ACM Transactions on Database Systems
  • Rob, P., & Coronel, C. (2016). Database Systems: Design, Implementation, & Management. Cengage Learning.
  • Date, C. J. (2019). An Introduction to Database Systems. Pearson.
  • Teorey, T. J., Das, S., & Dorn, B. (2011). Database Modeling and Design. Morgan Kaufmann.
  • Sergio, J. G. (2017). Data Modeling for the Business: A Handbook for Aligning the Business Resource with the Enterprise Data. Morgan Kaufmann.
  • Coronel, C., & Morris, S. (2015). Database Systems: Design, Implementation, & Management. Cengage Learning.
  • Hoffer, J. A., Ramesh, V., & Topi, H. (2016). Modern Database Management. Pearson.
  • Khan, M. I. (2018). Principles of Database Design. Wiley.

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