File Processing Systems Quiz

Course Information

• Course: Database
• Stage: 3rd Stage
• Weeks: 1, 2, and 3

General Definitions

• 1- Data:

  • A collection of raw facts and figures not yet processed.
  • Raw means the facts have not been processed to give their exact meaning.
  • Data is collected from various sources for diverse purposes.
  • Data can include numbers, characters, symbols, and pictures.
  • Data is a crucial resource for organizations.
  • Resources are things valuable to an organization, including buildings, furniture, vehicles, machinery, and employees.
  • Data is a resource because it helps make informed and timely decisions, enabling effective utilization of other resources.
  • Data must be in a proper format for effective decision-making.
  • Example: Student admission forms contain student name, father's name, address, and other raw facts.

• 2- Information:

  • Processed data, organized and processed to be meaningful.
  • More meaningful than data and used for informed decisions.
  • Data is processed to become information. Information can be used again in further processing and becomes data.

File Processing System vs. Databases

• 1- File Processing System:

  • An older method of storing and managing data in files (on tape or disk).
  • Each department in an organization typically had its own set of files.
  • Files were designed specifically for their own applications and records were not related.
  • Storing the same data in multiple locations. -Difficult to maintain data consistency.
  • Data redundancy and inconsistency. -Data isolation. -Integrity problems. -Program data dependency. -Atomicity problem.

• 2- Databases:

  • An organized collection of related data stored efficiently in a compact manner.
  • Data is stored in a structured manner allowing for easy access and retrieval.
  • Facilitates the collection of data from different sources and related to particular topics such as students, employees.
  • Data in a database is arranged in tables, and search of required data is quick.
  • Data security is maintained, and concurrent access and use is possible. -Data redundancy is controlled. -Support for consistency constraints. -Improved backup and recovery. -Data independence.

Data Models

• 1- Data Models:

  • A set of concepts used to describe the structure of data in a database.
  • A database model visually shows a database’s logical structure.
  • Data models aid in the development of information systems, by defining and structuring data used in future systems.
  • There are several types of data models, which include hierarchical, network, relational, and object-oriented databases.

• 1.1 - Hierarchical databases:

  • Data is organized as a tree-like structure.
  • Each child record has only one parent, with one parent having multiple child records.
  • Data is easily accessed from the root node.
  • Advantages: Easier addition/deletion of new information. Quickly processing data from the root. One-to-many relationship
  • Disadvantages: Data redundancy, retrieval of data from top to bottom is slow. Does not support many-to-many relationship

• 1.2 - Network databases:

  • Data is organized in a graph structure.
  • A record can have more than one parent.
  • Simpler and easier to manage than hierarchical models when many-to-many relationships are needed
  • Advantages: Data can be managed more effectively than hierarchical models; allows easy management for one-to-many and many-to-many relationships.
  • Disadvantages: Storage structure is complex. Data retrieval is difficult and might be slow to process. The insertion, deletion and updatation of data requires the change in multiple pointers adjustment. Data is difficult to manage in complex structures.

• 1.3 - Relational databases:

  • Data is stored in two-dimensional tables with rows and columns.
  • Tables are related to each other through keys.
  • Advantages: Data redundancy is eliminated, data is consistent, data access is easier, easier to maintain security constraints.
  • Disadvantages: Difficult managing large quantities of data, expensive to implement

• 1.4 - Object-oriented databases:

  • Data is stored as objects that have attributes and relationships.
  • Represents real-world objects, including attributes and methods.
  • Advantages: Supports complex data types such as graphics, audio, video. Better support for object programming. Easier reuse of code.
  • Disadvantages: More complex structure, lack of universal standards, may be hard to map object-oriented concepts to relational data.