Information Management - Unit 1

Information Management - Unit 1

• Data: Raw facts or concepts, often useless in their natural form.
• Information: Data processed to be meaningful and understandable by users. This often involves organizing, presenting in context, summarizing, or graphing data.
• Databases: Structured databases contain numerical and textual data (organized neatly). Unstructured databases include sensory data like audio-visual content (qualitative data), unsuitable for conventional tools.
• Variables: Data that vary in size.
• Metadata: Data about data, describing it. Provides information about data aspects. It summarizes basic information about data.
• Types of Information: Data in context (requires reading, like text) and summarized data (like charts and graphs).
• DBMS (Database Management System): Software that lets users create, maintain, retrieve, and access data.
• CRUD: Create, read, update, and delete/archive (operations in databases).
• Hierarchy of Data: Character (letter, number, or symbol), Fields (characters in a group), Record (rows of multiple fields/data in a table), and Data file (collection of interrelated records/table of values).
• Database vs File System: A database is a collection of interrelated data files, or tables, and is more complex than a file management system which is computerised and dependent in a program and also redundant.

Information Management - Unit 2

• Database System > Presence of DBMS > Relational: Can recover data even when program crashes, possible data sharing across the company, and preserve data integrity. Consistent data integrity.
• Database Application: Software for collecting, managing, and providing information to end-users (searching, sorting, manipulation and sharing of data). Lets users manipulate data in a DBMS.
• Front-end/UI: User interface (visual elements)
• DBMS: Database management system
• Back-end/DB: Database (storage location for data/program used to manage data).
• Types of DB Apps: Personal (single users), Multitiered client-server (multi-users), and enterprise (whole organization).
• Database Applications and Types: Database applications are software programs designed for collecting, managing, and delivering info to users. Types include software programs managing and delivering info efficiently to end users and also allowing users to manipulate data in a DBMS.

Information Management - Unit 3

• Data Independence: Physical data independence is changing the internal database without affecting the conceptual or external views.. Conceptual data independence means changing the conceptual without effecting the external schema.
• DB system environment: The hardware, software, applications, and people used to run a database (hardware refers to physical devices to manage the database (all tangible/physical), software refers to intangible elements to help in controlling and managing the database and contents (like DBMS), people include application programs, system administrators, database administrators, database designers, and end-users (data entry).
• DB Development Process: Uses the System Development Life Cycle (SDLC).
• Planning: Enterprise modeling and conceptual data modelling.
• Analysis: This stage would also be part of the planning stage.
• Design: Local database design, physical database design.
• Implementation: Data implementation and data maintenance.
• Three level architecture & data independence: external, conceptual, and internal levels represent different user views of the database and how data is accessed.

Information Management - Unit 4

• Entities: Objects or concepts important to a business.
• Entity instance: Specific examples of an entity (e.g., a particular car).
• Entity type: A category or group of entities (e.g., the category of cars).
• Relationships: Links between entities, often through attributes (links strong to weak entities).
• Relationship instance: Specific example of a relationship between two or more entities(correspond to a row in a related table).
• Relationship type: Category of relationship (like many-to-many relationships).
• Identifiers (keys): Attribute(s) uniquely identifying entity instances (simple identifiers (one attribute) versus composite identifiers (multiple attributes)).
• Business rules: Statements that define business constraints or aspects of the business (rules defined by software that auto-determine the business rules).
• Cardinality of Relationships: Represents specific relationships that one entity can have with another.
  • One to one - each entity has at max one related entity
  • One to many - one entity has many entities but each entity doesn't have many entitites.
  • Many to many - each entity can have many entities, and each entity can have many entities.
• Types of Relationships: one-to-one, one-to-many, many-to-many
• Strong Entities: Stand-alone entities, not dependent on other entities.
• Weak Entities: Dependent on other entities. Their existence depends on the primary key of another entity
• Data independence: The physical, view, or logical schemas of a database can be changed without affecting how programs or users interact with the data.

Information Management - Unit 5

• Data Normalization: Process of organizing data into schemas, to improve data integrity and avoid data redundancies
• Anomalies: Insertion, deletion, and modification
• Normal Forms: First Normal Form (1NF): Remove repeating Groups. Second Normal Form (2NF): Eliminate redundant data dependent on part of the primary key. Third Normal Form (3NF): Elminate transitive dependencies
• Correspondence Between E-R Model and Relations: Relations (tables) map to entity types, many-to-many relationships and vice-versa.
• Entity Integrity: No primary key attributes can be null.
• Referential Integrity: foreign keys must correspond with primary keys in another table, or they can be null.
• Types of relations: One, two, and many relational forms
• Normalization steps: Start with 1nf, then 2nf, and lastly 3nf.
• Well-Structured Relation: Contains minimal data redundancy.

This quiz covers essential concepts in Information Management, including the distinctions between data and information, the structure of databases, the role of metadata, and the functions of DBMS. Understanding these foundational elements is crucial for effectively managing and utilizing information in various contexts.