The geographic objects were designed by using the OMT methodology. The application was built with the Java programming language. The objects were made persistent by using the IUS database management system. A web user interface was developed to show the geographic data. Data modeling was done by using points, lines, polylines and polygons. The data stored in the database could be exported and used by a client who runs a web user interface. Our representation gives the description to have an homogeneous geographic data representation to be used in a geographic database server.
Get The Basics On NoSQL Databases: Object-Oriented Databases
The user can then access and use the data stored in the database. The web user interf. Other papers in this volume. Try Lucidchart.
Object-oriented Data Model
It's quick, easy, and completely free. You may choose to describe a database with any one of these depending on several factors.
The biggest factor is whether the database management system you are using supports a particular model. Most database management systems are built with a particular data model in mind and require their users to adopt that model, although some do support multiple models.
In addition, different models apply to different stages of the database design process. High-level conceptual data models are best for mapping out relationships between data in ways that people perceive that data. Record-based logical models, on the other hand, more closely reflect ways that the data is stored on the server. Selecting a data model is also a matter of aligning your priorities for the database with the strengths of a particular model, whether those priorities include speed, cost reduction, usability, or something else.
The most common model, the relational model sorts data into tables, also known as relations, each of which consists of columns and rows. Each column lists an attribute of the entity in question, such as price, zip code, or birth date. Together, the attributes in a relation are called a domain. Each row, also called a tuple, includes data about a specific instance of the entity in question, such as a particular employee. The model also accounts for the types of relationships between those tables, including one-to-one, one-to-many, and many-to-many relationships.
Within the database, tables can be normalized, or brought to comply with normalization rules that make the database flexible, adaptable, and scalable.
When normalized, each piece of data is atomic, or broken into the smallest useful pieces. The model was introduced by E. Codd in The hierarchical model organizes data into a tree-like structure, where each record has a single parent or root. Sibling records are sorted in a particular order.
That order is used as the physical order for storing the database. This model is good for describing many real-world relationships. The network model builds on the hierarchical model by allowing many-to-many relationships between linked records, implying multiple parent records.
Object-Oriented Programming & NoSQL Databases | MarkLogic
Based on mathematical set theory, the model is constructed with sets of related records. Each set consists of one owner or parent record and one or more member or child records. A record can be a member or child in multiple sets, allowing this model to convey complex relationships. This model defines a database as a collection of objects, or reusable software elements, with associated features and methods.
There are several kinds of object-oriented databases:. A multimedia database incorporates media, such as images, that could not be stored in a relational database. A hypertext database allows any object to link to any other object. What is Object-Oriented Data Model? This forces a complete encapsulation of objects.
The object then executes the method for that operation. We use i1, i2, i3,. Object Structure and Type Constructors 36 Specifying Object Behavior via Class Operations contd. Encapsulation of Operations 39 An object B is said to be reachable from an object A if a sequence of references in the object graph lead from object A to object B. Subtype inherits all the functions of the Supertype. Inheritance: Example 2 contd. Exercise 51 1.
What is OID? How persistent objects are maintained in OO Database? Define state of an object. Distinguish between persistent and transient objects.
Distinguish multiple inheritance and selective inheritance in OO concepts. What is the difference between structured and unstructured complex object? Differentiate identical versus equal objects with examples.
You just clipped your first slide!