Practical connections paper.

Assignements I done before

1. Throughout the chapter, you have reviewed various examples of B2B and B2C stores where 1-1, 1-M, and M-M relationships are portrayed. Can you provide example use cases where a business would need data to be fairly rigid, applying a 1-1 model? How about fairly lenient, applying a M-M model?

2. SQL is a pervasive querying language. While there is one primary SQL dialect that all SQL RDBMS implementations must support, and that's ANSI SQL, each database platform comes out with its own context. Each of these dialects has its own  DDL (Data Definition Language). DML (Data Manipulation Language). and DQL (Data Query Language). Other than for marketing purposes (to sell the product as unique), what is the value of creating a new variation of a SQL dialect. Provide an example of one SQL dialect as part of your write-up. 

3. If your boss asked you to create a database that integrated logical design best practices, what are the three most important features you would integrate in your end solution? Remember to not only just state them, but explain why and show examples. Don't repeat the same examples of others. That constitutes cheating. 

4. The use of keys are instrumental in database management. Primary keys allow for distinct records and foreign keys tie records together to create unique relationships between two or more entities and/or tables. In Blockchain, we know that a hash is the equivalent to a key - and makes the chain secure and indisputable (or so we think). Why is it then that with an RDBMS, a primary key and foreign key can still create redundancy, thereby causing data anomalies? Can the same be said about blockchain?

Chapter Objectives

· Explain why humankind’s interest in data goes back to ancient times.

· Describe how data needs have historically driven many information technology developments.

· Describe the evolution of data storage media during the last century.

· Relate the idea of data as a corporate resource that can be used to gain a competitive advantage to the development of the database management systems environment.

· Explain the concept and practical use of data modeling.

· Recognize which relationships in the business environment are unary, binary, and ternary relationships.

· Describe one-to-one, one-to-many, and many-to-many unary, binary, and ternary relationships.

· Recognize and describe intersection data.

· Model data in business environments by drawing entity-relationship diagrams that involve unary, binary, and ternary relationships.

· Discuss the problems encountered in a non-database information systems environment.

· Discuss the nature of data.Define data-related terms such as entity and attribute.

· Define storage-related terms such as field, record, and file.

· Identify the four basic operations performed on stored data.

· Compare sequential access of data with direct access of data.

· List the five basic principles of the database concept.

· Describe how data can be considered to be a manageable resource.

· List the three problems created by data redundancy.

· Describe the nature of data redundancy among many files.

· Explain the relationship between data integration and data redundancy in one file.

· Explain why providing support for such control issues as data security, backup and recovery, and concurrency is an important feature of the database approach

· Explain why providing support for data independence is an important feature of the database approach.

· State the primary defining feature of a database management system.

· Explain why the ability to store multiple relationships is an important feature of the database approach.

· Describe SQL as a relational data manipulation language.

· Explain that you can create and update relational tables using SQL.

· Write SQL SELECT commands to retrieve relational data using a variety of operators, including GROUP BY, ORDER BY, and the built-in functions of AVG, SUM, MAX, MIN, and COUNT.

· Write SQL SELECT commands that join relational tables.

· Write SQL SELECT subqueries.

· Describe a strategy for writing SQL SELECT statements.

· Describe the principles of how a relational query optimizer works.

· Explain why the relational database model became practical in about 1980.

· Define such basic relational database terms as relation and tuple.

· Describe the major types of keys including primary, candidate, and foreign.

· Describe how one-to-one, one-to-many, and many-to-many binary relationships are implemented in a relational database.

· Describe how relational data retrieval is accomplished in concept with the select, project, and join operators.

· Understand how the join operator facilitates data integration in relational database.

· Describe how unary and ternary relationships are implemented in a relational database.

· Explain the concept of referential integrity.

· Describe how the referential integrity restrict, cascade, and set-to-null delete rules operate in a relational database.

· Describe the concept of logical database design.

· Design relational databases by converting entity-relationship diagrams into relational tables.

· Describe the data normalization process.

· Perform the data normalization process.

· Test tables for irregularities using the data normalization process.

· Describe the concept of physical database design.

· Describe how a disk device works.

· Describe the principles of file organizations and access methods.

· Describe how simple linear indexes and B+-tree indexes work.

· Describe how hashed files work.

· List and describe the inputs to the physical database design process.

· Perform physical database design and improve database performance using a variety of techniques ranging from adding indexes to denormalization.

· List several limitations in the relational database model.

· Describe the object-oriented database concept.

· Model data using such complex relationships as generalization and aggregation, and such concepts as inheritance and polymorphism.

· Describe the benefits of encapsulation.

· Describe the value of developing abstract data types.

· Explain what an object/relational database is.

· Define and compare data administration and database administration.

· List and describe the advantages of data administration.

· List and describe the advantages of database administration.

· List and describe the responsibilities of data administration.

· List and describe the responsibilities of database administration.

· Explain the concept of metadata.List and describe such metadata realizations as passive and active data dictionaries, relational DBMS catalogs, and data repositories.

· List the major data control issues handled by database management systems.

· List and describe the types of data security breaches.

· List and describe the types of data security measures.

· Describe the concept of backup and recovery.

· Describe the major backup and recovery techniques.

· Explain the problem of disaster recovery.

· Describe the concept of concurrency control.

· Describe such concurrency control issues and measures as the lost update problem, locks and deadlock, and versioning.