Management Information Systems Notes
Data in Organizations
- Transactional Data (internal): Data from day-to-day operations (customer, financial, product data).
- Non-transactional Data (external): Data from external sources (social media, internet, sensors, purchased data).
Big Data
- Massive unstructured/structured data sets from various sources.
- Volumes too large for typical DBMS.
- High volume, velocity, variety.
- Big data analysis analyzes all data, while transactional data analysis analyzes small subsets.
File Organization Terms
- Database: Group of related files.
- File (table): Group of records of the same type.
- Record: Group of related fields.
- Field: Group of characters.
- Entity: Person, place, or thing.
- Attribute: Characteristic describing an entity.
Data Hierarchy
- Bit (0 or 1) -> Byte (character) -> Field -> Record -> File -> Database.
Database Management Systems (DBMS)
- Relational Database: Collections of related tables.
- DBMS: Interfaces between applications and physical data files.
- Solves problems of traditional file environment.
- Data dictionary: Definitions of data elements.
Relational DBMS
- Data represented as two-dimensional tables.
- Entity-Relationship Data Model: track entities (order, customer, supplier) and attributes (OrderNumber, CustomerNumber).
- Identifier: Uniquely identifies one entity instance (CustomerNumber).
Designing Relational Databases
- Conceptual (logical) design: Abstract model.
- Normalization: Minimizes redundant data, builds relationships using primary and foreign keys.
Keys
- Key field: Uniquely identifies each record.
- Primary key: Field in table used for key fields.
- Foreign key: Primary key used in another table for look-up.
Structured Query Language (SQL)
- Data manipulation language to add, change, delete, retrieve data.
- SELECT: Creates a subset of data.
- JOIN: Combines tables using keys.
- PROJECT: Creates a subset of columns in a table.
Non-Relational Databases (NoSQL)
- Flexible data model, no specific structure required.
- Data stored across distributed machines (nodes).
- Easier to scale, handles large volumes of unstructured data.
- Fault-tolerant: Data replicated across machines.
- Used through cloud services (DBaaS) or private clouds.
Business Intelligence (BI)
- Transformation of data into actionable knowledge.
Business Intelligence Infrastructure
- Data warehouse: Stores current and historical data.
- Data marts: Subset of data warehouse for specific functions.
- NOSQL database (Hadoop): Enables distributed parallel processing of big data.
- Analytic platforms: High-speed platforms for large datasets using relational and non-relational tools.
BI Users
- Casual users: Organizational members who retrieve data (MIS for routine reports).
- Power users/business analysts: Use DSS for sophisticated analysis, custom reports, OLAP, data mining.
Online Analytical Processing (OLAP)
- Multidimensional data analysis.
Data Mining
- Finds hidden patterns and relationships in datasets.
Prediction
- Uses variables to predict unknown values.
- Regression: Predicts a value based on other variables.
Text Mining
- Extracts key elements from unstructured data.
- Sentiment analysis: Uses positive and negative word lists.
- Topic analysis: Identifies main ideas in the text.
Association Rules
- Determines products people purchase together.
Clustering (Segmentation)
- Groups objects into clusters based on similarity.