Understanding Differences: File Systems vs Databases in Data Management - Prof. Peter Weis, Study notes of Introduction to Business Management

Download Understanding Differences: File Systems vs Databases in Data Management - Prof. Peter Weis and more Study notes Introduction to Business Management in PDF only on Docsity! Database I: What is a database? Computer record-keeping system: automated rolodex, organized connection or logically related data; text, numeric, dates, audio, video, spreadsheets, etc; Basic features: add new data at end, insert new data in the middle, retrieve data, update/modify existing data, delete data Problems with file systems: waste of space to have duplicate data, maintaining data causes problems; biggest problem: data changes in 1 file can cause inconsistencies and compromises in data integrity Database Approach: A software system that is used to create, maintain, and provide controlled access to user databases; DBMS manages data resources like an operating system manages hardware resources; Benefits: Data independence (program/data separation), reduced data redundancy, inconsistency can be avoided, data sharing, standards can be enforced, security can be applied, integrity can be maintained, conflicting requirements can be balanced (enterprise wide optimization); INCONSISTENCY is ONE OF THE PRIMARY PROBLEMS W/ REDUNDANT INFORMATION Relational Model: man ways to build database system: relational, hierarchical, network, object oriented; relational: A database is a collection of data organized in a particular way; A relational database stores its data in tables MS Access (for example) is a relational database, so its data is stored in tables; properties: 1-No duplicate rows: Result of the mathematical definition of a relation. Sets in mathematics do not contain duplicates. As stated before, we can have databases (tables) with duplicate records, 2-Rows are unordered: Again, this is a mathematical set and sets have no ordering. In a table or database, there is ordering. At minimum, there is the physical ordering or entry of records 3-Fields/Attributes are unordered: Same argument. This normally can be followed in a table or database as attributes (or fields) are usually referenced by name; 4-Fields/Attributesare atomic Each field or attribute has only one value, not a list of values. This also implies that relations do not contain repeating groups (i.e. - they are normalized). 5-Tables have names; 6-Fields (columns) have names; Primary Keys: Primary Keys Relational Model Property 1 says all rows must be unique -> no duplicates; This implies that each row is uniquely identifiable, A Primary Key is the attribute, or combination of attributes, that uniquely identifies each row; Relational rule: “one fact in ONE place”; In the relational model, we break up a business problem into “subject” tables thus, we have customer tables, order tables, shipping tables, inventory tables, student tables, course tables, etc. We link these tables together via the Primary Keys (PKs) and something called Foreign Keys (FKs); Key Points: Database Systems organize data in a logical way and improve organizational performance by: Separating business systems from the data, Allowing sharing, Eliminating redundancy, Relational systems are by far the most common type of DBMS, Store data in tables, Tables are “linked” together via relationships, Tables have 6 key properties (PK, etc.), Power of the Relational Model comes from being able to run a query on any table and reach any other table in the system by following “links”, The system’s ability to protect itself and build trust via “integrity” rules Data Warehousing: The data warehouse provided the ability to support decision making without disrupting the day-to-day operations; Data warehouse – a logical collection of information – gathered from many different operational databases – that supports business analysis activities and decision-making tasks; The primary purpose of a data warehouse is to aggregate information throughout an organization into a single repository for decision-making purposes; Data Warehouse: a subject- oriented, integrated, time-variant, nonvolatile collection of data; Organized around key subjects (customers, sales, products) of the enterprise, Stored data has consistent naming conventions, formats, structures, Stored data contains a time-dimension (history) Stored data is continuously loaded & refreshed but cannot be updated by users (read only); Extraction, transformation, and loading (ETL) – a process that extracts information from internal and external databases, transforms the information using a common set of enterprise definitions, and loads the information into a data warehouse; Data mart – contains a subset of data warehouse information; Two-level architecture for small-med firms, three-level for large; A data mart is a “data warehouse lite” Primary reason for a data mart is performance: Searching a data warehouse can be very time consuming and machine intensive, A data mart is a subset of a data warehouse, Focused on a subject (Sales data only), Focused on time (last 6 months only), Aggregated data (only monthly summaries), Problem with data marts is that every time data is updated in DW, all data marts must be updated as well (can be many); To build a data warehouse must do “data reconciliation”, commonly known in the field as ETL (Extract-Transform-Load): Data are extracted from various source databases (could be hundreds), Data is transformed, cleaned, and integrated, Then loaded into a data warehouse; If three-level, then selected data is derived and aggregated from the data warehouse and put into data marts (customized to user); capture: static extract=snapshot at point in time, incremental extract=only changes since last static extract; scrub: fix errors-misspellings, wrong dates, mismatched, etc; decode, reformat, time stamp, convert, merge, etc; transform: selection-data partitioning, joining-data combining, aggregation- summarizing data; field-level-one field to one field, multi-field-many to one or one to many; load: refresh-bulk rewriting of target data at periodic intervals, update mode: only changes in source data are written to data warehouse; issues in extract: many different forms, large amount of data, people don’t to cooperate, must reindex every time data is added; multidimensional/ uses: Understand your data so as to improve your business processes (incremental), Understand your data to better understand behavior and/or phenomena (OLAP –> historical), Seek to discover meaningful patterns and rules (Data Mining –> predictive); Data Mining: Data mining – the process of analyzing data to extract information not offered by the raw data alone Data mining is a predictive tool: Tries to predict future trends, patterns by extrapolating the past need data-mining tools-uses a variety of techniques to find patterns and relationships in large volumes of information and infers rules that predict future behavior and guide decision making; Recap: Hard to get good data quality, Hard to collect & store data (ETL), Analysis (BI) is sophisticated Business Model: random notes: Information Technology (IT) – the methods, standards, and products used to conduct activities (raw technology); Information Systems (IS) - any computer-based system that people use to work with information and support the information and information-processing needs of an organization; Management Information Systems (MIS) – the function that plans for, develops, implements, and maintains IT hardware, software, and applications that people use to support the goals of an organization; a business is the sum of its business processes: Business process – a standardized set of activities that accomplish a specific task, such as processing a customer’s order, ship a package, order supplies; FIVE FORCES MODEL: Buying power: high when many choices to choose from, Supplier power: high when buyers have low choices, Threat of substitute products or services: high when many alternatives to choose from, Threat of new entrants: high when easy to enter market, Rivalry among existing competitors: high when competition fierce, comp strategies: cost, differentiation, industry wide, focus; porter model: segment strategy, diff strategy, cost leadership; Value chain – views an organization as a series of processes, each of which adds value to the product or service for each customer Competitive Model: Competitive advantage – a product or service that an organization’s customers place a greater value on than similar offerings from a competitor; First-mover advantage – occurs when an organization can significantly impact its market share by being first to market with a competitive advantage; sustainable competitive advantage if: Affects firm value in a positive way (advantage), Not too many competitors can imitate it (competitive), Can keep it up (sustainable); hard to maintain but If a firm can achieve competitive advantage: It should be able to earn higher than average profits, Often this is reflected in a high stock price (the financial markets recognize that a firm has a competitive advantage), Having a competitive advantage in one area or product line can often yield positive “spillover” effects to other products; Principles of competitive advantage: create a new product/service, enhance products/service, differentiate products/services, lock in customers/buyers, lock in suppliers, raise barriers to market entry, establish alliances, reduce costs; Organizations can undertake high-profile strategic initiatives including: Supply chain management (SCM), Customer relationship management (CRM), Business process reengineering (BPR), Enterprise resource planning (ERP); Four basic components of supply chain management include: Supply chain strategy – strategy for managing all resources to meet customer demand; Supply chain partner – partners throughout the supply chain that deliver finished products, raw materials, and services.; Supply chain operation – schedule for production activities; Supply chain logistics – product delivery process; Customer relationship management (CRM) – involves managing all aspects of a customer’s relationship with an organization to increase customer loyalty and retention and an organization's profitability, CRM is not just technology, but a strategy, process, and business goal that an organization must embrace on an enterprisewide level; Business process reengineering (BPR) – the analysis and redesign of workflow within and between enterprises; Enterprise resource planning (ERP) – integrates all departments and functions throughout an organization into a single IT system so that employees can make decisions by viewing enterprisewide information on all business operations Flatteners: 1. Fall of the Berlin Wall The events of November 9, 1989, tilted the worldwide balance of power toward democracies and free markets; 2. Netscape IPO The August 9, 1995, offering sparked massive investment in fiberoptic cables; also opened the Internet (browser); 3. Work flow software The rise of applications from PayPal to VPNs enabled faster, closer coordination among far-flung employees; 4. Open-sourcing Self-organizing communities, such as Linux, launched a collaborative revolution; 5. Outsourcing Migrating business functions to India saved money and a Third World economy; 6. Offshoring Contract manufacturing elevated China to economic prominence; 7. Supply-chaining Robust networks of suppliers, retailers, and customers increased business efficiency; 8. Insourcing Logistics giants took control of customer supply chains, helping mom-and-pop shops go global; 9. Informing Power searching allowed everyone to use the Internet as a “personal supply chain of knowledge”; 10. Wireless Wireless technologies pumped up collaboration, making it mobile and personal; Triple Convergence: New technologies; Horizontal vs. vertical relationships; New players entering the game: Friedman estimates 5% of 3 billion people = 150 million new “competitors” Internet: The Internet & the Digital Economy has changed the choices and the control: It has introduced much competition and changed the playing field by: Changing the form of content (it’s all bits baby!), Eliminating the control of the code layer; Cyberspace frees us from real constraints, Digital content can be copied perfectly & almost for free, Digital content can be moved instantly and almost for free, Digital content can be replicated in many places at the same time; The Internet changes everything! It eliminates the power of the middle (code) and moves it to the ends (content creators & consumers); competition: By shifting from the real (physical space) network for delivering content to cyberspace; new products: example google; new markets: Cyberspace removes barriers to distribution, Thus, small niche players can find markets that were impossible before; new distribution: As is probably obvious by now, the Internet can radically reduce the costs of distribution creating new business opportunities (often disruptive); last thoughts: Technology has created digital goods, The Internet removes real-space barriers, This allows new thinking, new competition, new ways to deploy new ideas – a new form of innovation, Can invert traditional thinking Value of Data: Key performance indicator (KPI) – measures that are tied to business drivers; Efficiency IT metric – measures the performance of the IT system itself including throughput, speed, and availability, “Doing things right” (optimize process); Effectiveness IT metric – measures the impact IT has on business processes and activities including customer satisfaction, conversion rates, and sell-through increases; Benchmarking – a process of continuously measuring system results, comparing those results to optimal system performance (benchmark values), and identifying steps and procedures to improve system performance; Transactional information – encompasses all of the information contained within a single business process or unit