AIS Final Exam Ch. 6

SELECT command

A DQL command that retrieves data from a database and that has the basic form SELECT [field name] FROM [table name].

Technical architecture specifications

A document created by the lead systems analyst that identifies software, hardware, and network technologies a system will need.

Systems Model

A model created by the lead systems analyst that includes graphical models such as flowcharts and data flow diagrams (DFDs) to describe in technical detail how a system will interact with users, other technologies, and systems processes and components.

Scope Creep

A problem that occurs when a project evolves during development beyond its original specifications and becomes too large to meet its deadlines. It is often the result of end users asking "Can it also do this?" and adding more features. Scrum addresses this risk by ordering the suggestions of the end users by priority.

Systems Development Life Cycle (SDLC)

A project management framework with clearly defined stages for creating and deploying new systems. The SDLC includes seven stages: planning, analysis, design, development, testing, implementation, and maintenance.

Referential Integrity

A property of database design which states that a foreign key cannot be entered into a table unless it exists as a primary key in the base table. For example, you cannot enter the customer ID into the Orders table if the customer ID does not exist in the Customers table.

Scrum

A set of project management practices focused on daily communication and flexible planning. This flexible planning allows mid-project changes that do not impact budgets or timelines. Scrum breaks a systems development project into short cycles of work. After each cycle, the team reflects on successes and failures, and appropriate adjustments are made before continuing to the next cycle.

Transaction Control Language (TCL)

A subset of SQL that interacts with data manipulation language (DML) commands when transactions are processed in a database.

Waterfall methodology

A systems development methodology that breaks the systems development life cycle (SDLC) into formal stages, which must be executed in a linear fashion. Waterfall usually uses the seven stages of the SDLC framework, but companies can customize this approach by adding, removing, or renaming stages.

User Acceptance Testing (UAT)

A type of system testing in which a select group of end users get access to the system so they can use the system and verify that it meets their expectations. They are often provided scenarios to execute and then record their observations and any errors encountered.

Project Plan

Identifies the system scope and project goals. Covers three elements: -Critical factors that must be met for the project to be successful -A defined project scope, including an overview of goals and limitations -Milestones and responsibilities that break down project goals into timelines and identifying individuals responsible for each goal

Requirements definition

Formal documentation of the final goal of a project, which identifies the steps needed to achieve the goal and outlines the overall system plan.

primary key (PK)

If the key is the unique ID of a table, such as the customer ID in the Customers table, it's called __

WHERE clause

In SQL, a clause added to a SELECT statement to filter which records the query returns by adding values such as mathematical comparisons (=, <, <=, >, >=, <>) or special operators (BETWEEN, LIKE, IN, etc.).

Sprint Backlog

In scrum, a list of what the core team will develop during the current sprint.

Timeboxing

In scrum, a practice that involves allocating a fixed length of time to each activity to both define the activity and limit the amount of time dedicated to it.

sprint

In scrum, a single iteration of a systems project that includes multiple systems development life cycle stages. Sprints are often biweekly increments, after which the core team regroups to discuss what went well and how to improve work during the next sprint.

Variable

In the context of object-oriented databases, a name assigned to similar characteristics of objects in a class, much like fields in a relational database.

Crow's Foot notation

Now that the cardinality and constraints between the Orders and Customers tables are identified, the physical ERD is enhanced by adding shapes to the end of each line between entities using a formal diagramming notation called __. Each side of the relationship line has two symbols: one for the plurality constraint and one for the optionality constraint

testing stage

The fifth stage of a systems development life cycle project, when a system is evaluated against the design specifications and requirements definition to ensure that it meets expectations.

Conceptual Design

The lead system analyst creates a __ summarizing the system's purpose, resource requirements, and planned flow of data through the system.

System go-live

The point after a system is developed and tested when it is officially available to users. This critical event in the systems development life cycle is followed by ongoing maintenance of the live system.

Entity Integrity

The primary key cannot be null, which means empty. This is called __.

Analysis Stage

The second stage of the SDLC. Systems analysts meet with end users to understand business requirements of the project, which is a critical step in a systems development project. The information captured here is the roadmap for programmers.

key

The unique IDs that identify the records in the database

planning stage

This stage includes defining the scope of the project, identifying necessary resources, and determining if the project will likely be successful. These three steps can be performed in any order and often occur in tandem.

foreign key (FK)

When the key is referenced by another table, such as the customer ID in the Orders table

SQL statement

Written syntax for communicating SQL commands to a database.

Agile Methodology

a group of SDLC methodologies that focus on iterative development, collaboration, and self-organized, cross-functional teams. Characterized by multiple short cycles of work that simultaneously include multiple SDLC stages, Agile involves end users in real time decision making as the project progresses.

object-oriented database

a hybrid database because it has a relational database framework with the data presented and stored in a form other than tables. It can store both structured numbers and text and complex unstructured data

Product Backlog

a list of all the desired features for the system being developed

Data Modeling

allows us to document data that will be stored in a database and identify its specifications. These specifications include the fields that will be stored, the associations between fields and tables, and the rules that govern the associations

feasibility study

an analysis of the technical, economic, and operational factors that will impact the project

object

an item contained within a class

business rule

are written statements that precisely capture the business event occurring during a process as it relates to the entities in the database. When written correctly, business rules define the entities, relationships, cardinalities, and constraints of the database.

implementation stage

begins when the system is moved into production and goes live for use in the company. This stage is the culmination of the work put into the systems development project

Data Definition Language (DDL)

changes the structure of a database by adding or changing tables and relationships

class

connects similar objects together

maintenance stage

during this stage the system is monitored, updated, and changed

data redundancy

exists when the same piece of data is stored in multiple places.

Data Control Language (DCL)

grants access to or removes access from a database user

Data Manipulation Language (DML)

modifies the data within a database

Development Stage

programmers create the system based on technical specifications identified in the design stage

data dictionary

provides a detailed description of and data type (text, numeric, date, etc.) for the fields located in each table. A __ provides descriptions that end users can reference when they need data from the database

data query language (DQL)

retrieves data from a database based on user requests

JOIN operator

retrieves interconnected data from related tables by declaring a primary key and foreign key relationship as the join column

NoSQL database

stores each item individually, rather than in rows and columns, and retrieves them by using key values. There is no structured schema, resulting in a flexible storage solution for unstructured data

Product Increment

the current version of the system

Graphical User Interface (GUI)

the lead systems analyst and core programmers create a mockup of the __ that shows the screen that will allow users to interact with the system. It includes colors, layout, and style decisions.

Cardinality

the numeric relationship between data in one table and data in another table

design stage

translates the requirements definition into technical specifications

null

which means empty