Chapter 5 The Database Environment

What are the objectives of the relational model?

1. A method to deal with consistency and redundancy issues relating to data management. 2. Data independence to keep an application separate from the data representation. 3. The concept of normalized data.

SQL is practically the same in all commercial RDBMS platforms with the exception of a few syntax differences. There are three section, what are they?

1. Data Definition Language (DDL). 2. Data Manipulation Language (DML). 3. Data Control Language (DCL).

What is normalization?

1. Defined as a methodology used to develop well-organized entities based on the organization's information needs. This method is used to eliminate redundancy, anomalies, and inconsistency in the database. 2. We want to normalize the table by ensuring that there is single value at each row and column.

What is 1NF?

1. First Normal Form. 2. Eliminates repeating groups. 3. Identify each entity with a primary key.

What is 2NF?

1. Second Normal Form. 2. Aims to remove partial dependencies and to avoid update anomalies. 3. Relation or table is in 1NF. 4. Eliminate partial dependencies.

What are the 5 normal forms?

1. The first three, referred to as First Normal Form (1NF). 2. Second Normal Form (2NF). 3. Third Normal Form (3NF); they are the most common.

What is conceptual modeling?

1. The process used to construct the architectural components of the database. This is critical to any successful information system development project. 2. In this phase the organization's data requirements are collected, detailed definitions are developed, and diagrams produced.

What is 3NF?

1. Third Normal Form. 2. Your relations are in 3NF if they are all in 2NF and all transitive dependencies have been removed. 3. Relations or tables are in 2NF. 4. All transitive dependencies have been removed.

For relations to subsist a database needs to be normalized to at least___.

1NF

What is the paper that produced the theory for the modern relational data model?

A Relational Model of Data for Large Shared Data Banks, by E.F. Codd in 1970.

What is a foreign key?

A field in the database that serves as a primary key in a different table or entity in the same database.

What is a primary key?

A unique identifying attribute or a combination of two attributes that identify the row in a relation.

What is the Internet?

A worldwide network of computer networks using the TCP/IP addressing scheme to interconnect millions of users.

What is nonprocedural language?

Allows the database administrator to conduct powerful task using relatively simple commands, unlike procedural language where many steps must be developed toward the execution of tasks.

What is a web application?

An application that end users access by using the Internet.

What is a composite key?

Combining two attributes to form a primary key.

What is the DDL?

Data Definition Language, which is used to develop the schema.

What is the DML?

Data Manipulation Language, which is used to manipulate the data in the database.

What is the notation used to describe the structure and limitations of data?

Data model

What is information?

Data that has been organized into some useful format to help the entity make critical business decisions.

Ruby on Rails identifies what type of language?

Domain-specific

T or F: A partial dependency is partially functionally dependent on the SQL.

F

T or F: Business analysts and developers maintain a close relationship.

F

T or F: SQL is different in all commercial RDNMS platforms.

F

T or F: Service-oriented architecture promotes loose coupling between similar information systems/

F

What is the schema?

Identifies the logical mapping of the entire database.

What is an attribute?

Or field, is the property used to describe a characteristic of the entity.

What is data?

Simply defined as "raw facts."

What is SQL?

Structured Query Language and was developed as a direct result of the System R project at IBM's San Jose research labs, known as SEQUEL.

T or F: Cloud computing will enable database developers to put more focus on business problems.

T

What is DBMS?

The Database Management System is the software used to manage, create, and maintain the database. The DBMS could host several databases for an organization.

What is the entity-relationship model?

The conceptual representation of the data in an organization.

What is the logical design?

The developer takes conceptual design and implements the database into a logical data model.

What is the physical design?

The portion of the database design process when the developed decides on the hardware needed, DBMS platform, indexing and file organization, and transformation of the entity relationship diagrams into relations. A performance and tuning plan would be developed at this stage.

What do modern organizations rely heavily on?

The transformation of data to information in order to make critical business decisions.

What is a subschema?

The virtualization of the database as seen by the database user.

Who developed the Internet?

Tim Berners-Lee developed the application that we know as the World Wide Web using the Objective-C language.

A___is a virtual table or logical object that presents data from one or more tables

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