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D. Tuples

In relational database system, we also call rows as tuples. So each row or tuple formed a record for an object. Look at the sample from a part of member table below

The highlighted row shows a record for the object that is member with ID 1002, from that tuple/row we can see the information for that object, like the member ID is 1002, his first name is Lou, his last name is Gandalf, his gender is male (M), he was born on May 12, 1981, his phone number is 6597720520, and his e-mail is gandalou@yahoo.com. Beside that, each tuple/row should have a primary key column that function as unique identifier for each record and make sure that there is no duplicate record because the primary key column can’t has a duplicate value.

Although in the Member Table above the member ID is ordered from 1001 to 1007, actually the order of the tuples/rows is not significant. We can store tuples/rows in without an order because it is an unordered set.

E. Relational Database

A relational database use relations/tables to store its data. The used table is in the form of two dimensional table, it consist of columns that has the data type, rows that store records of objects, and field or table’s cell that contain single value.
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admin Education, IDIC, Informatics C1025, database, IDIC, sql, table, tuple

II. Explanation on Database Terminologies

A. Database

Database is a set of related data organized in a manner that allow use, retrieval, access, and maintenance of the data. So, every table that contains the data in the database is related to the other table in the database, at least to one other table. There is no fully standalone table, if so, that table is actually not the part of the database, or actually we don’t need to store that table at all. For example, In Library.mdb all the tables there are related with the other table in order to store the information needed by the library. If I add a table that contain data about the kind of pet food in that database, this table’s data will not relevant and not related to any other table in the database, so I don’t have to store it there, because a database will only store data that are related with each other. Another example, a shop database may have data about the shop’s staff, the shop’s goods, and the goods’ supplier.

With the DBMS (Database Management System), software that allow a user manage a database, we can retrieve, use, edit, add, delete, create form, or make a report referring to the data in the database. For example, I can use the Library database that I have created to retrieve information about a library member, what book he borrow and when he borrow that book, and what’s the detail information about that book, or I can make a report about how many member borrow a book in a certain month, how many book borrowed in a month, and much more.

Ø  Advantages and Disadvantages of Database

The use of database to store data will give us some advantages, they are:

a)      Data Independence

The data in database is independent, the change or modification in the system or applications that use its data will not affect the data in the database. This mean low system or program maintenance.

b)      Data consistency

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admin Education, IDIC, Informatics C1025, database, sql, table, tuple

Hi! I want to share another assignment that I get during my International Diploma in Computing course from Informatics Computer School Singapore. This assignment is from C1025 Structured Query Language Module.. The main objective is that we have to make a Library database and then use that database as a reference to explain common terms in Relational Database System.

The Question:
Write detail notes to explain the following terminologies.
(a)    Database            [15]
(b)    Tables                [20]
(c)    Attributes            [10]
(d)    Tuples                [15]
(e)    Relational Database        [15]
(f)    Primary Keys            [10]
(g)    Composite Primary Key    [5]
(h)    Foreign Keys            [10]

Requirements for this paper are as follow:
•    Design and draw a database of 3 to 5 tables, to be used to explain the above terminologies. These tables must be realistic and related to indicate your understanding of RDB.
•    Your mock LIBRARY database must show the fields with realistic data.
•    You must display your in-depth understanding of the terminologies by their characteristic, purpose, advantage and disadvantages of their use (if any).
•    Use the mark allocation to serve as a guide for the volume and quality of your answer

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admin Education, IDIC, Informatics C1025, database, library database, sql, table, tuple