IM 342 Ch. 1,2,3,4

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________________ (partitioning a task) means to assign more resources to a task so it finishes sooner

"Crashing a schedule"

_______________ (parallelizing tasks) means to schedule related tasks at the same time, rather than sequentially

"Fast tracking tasks"

If a customer places an order, the constraint that ensures that the customer and the order remain associated is called a ______________ and it prevents an order from being entered without specifying who placed the order.

"relational integrity constraint"

A ______________ is a software system that is used to create, maintain, and provide controlled access to user databases.

Database management system (DBMS)

_______________ store, manipulate, and retrieve data in nearly every type of organization.

Databases

_______________- a collection of persons, places, objects, events, concepts (a table)

Entity Entity Instance - specific entity example (a row in a table)

______________ is a set of one or more entity types and associated relationships grouped into a single abstract entity type.

Entity cluster

The _______________ identifies the people, places, objects, things, events, or concepts, their characteristics and relationships, for an organization or business area and is a Visual Representation and Communication Tool

Entity-Relationship-Diagram (ERD)

When transforming an ERD into a table, how do you map a ternary relationship?

One table for each original entity and one for the associative entity. A ternary relationship maps to FOUR tables (n + 1).

Transaction processing systems are also known as ___________ and data management technologies can also be used as ____________.

Operational systems and Informational systems

This rule specifies that an instance of a supertype may simultaneously be a member of two (or more) subtypes.

Overlap rule

What are the two options for the disjoint constraint?

Overlapping Distinct

When transforming an ERD into a table, what does a Binary One-to-One relationship create?

PK from "most constrained side" Becomes FK on "less constrained side"

_______________ states that work expands to fill the time allowed

Parkinson's Law

This rule specifies that an entity instance of a supertype is allowed not to belong to any subtype.

Partial specialization rule

A ______________ is a set of specifications that describe how data from a logical schema are stored in a computer's secondary memory by a specific database management system.

Physical schema

A _________________ is a field that uniquely identifies a record in a table.

Primary Key (identifier)

A _______________ is a unique endeavor to produce a set of deliverables within clearly specified time, cost and quality constraints.

Project

The data you are interested in capturing about the entity (e.g., Customer Name) is called _______________.

an attribute

An ________________ is a property or characteristic of an entity or relationship that is of interest to the organization

attribute

What is done in the Logical Database Design phase of the Database SDLC?

-select logical database model -map entity-relationship diagrams -normalize data structures -specify business rules

What is the main output of the project planning phase?

A Work Breakdown Structure (WBS) which is essentially a task list

What is the difference between a required and an optional attribute?

A required attribute must have a value for an entity instance, whereas an optional attribute value may be null.

This constraint addresses whether an instance of a supertype must also be a member of at least one subtype.

Completeness constraint

________________ is the bottom-up process of defining a generalized entity type from a set of more specialized entity types.

Generalization

______________ is data that describes data.

Metadata

______________ states that if something can go wrong, it will

Murphy's Law

An entity *should* be what 3 things and *should not* be what 2 things?

SHOULD BE: An object that will have many instances in the database An object that will be composed of multiple attributes An object that we are trying to model SHOULD NOT BE: A user of the database system An output of the database system (e.g., a report)

The _______________ is a generic or template data model that can be reused as a starting point for a data modeling project.

Universal data model

What are the 3 components of the ER Model?

1. Entity 2. Attribute 3. Relationship

What are the 2 components needed to have an entity?

1. More than 1 instance 2. Multiple attributes

What 8 things make a project different from standard operational business activities?

1. unique in nature 2. defined timescale 3. approved budget 4. limited resources 5. risk 6. skills 7. tools 8. processes

A 'weather' column where only numbers can be entered is an example of which type of integrity constraint?

A Domain Constraint

What is the difference between a simple and a composite attribute?

A simple attribute is one that has no component parts. A composite attribute is an attribute that can be broken down into component parts. For example, Person Name can be broken down into the parts First Name, Middle Initial, and Last Name.

_______________ is an approach to database and software development that emphasizes "individuals and interactions over processes and tools, working software over comprehensive documentation, customer collaboration over contract negotiation, and response to change over following a plan."

Agile software development

A 'speed' column where only numbers that are positive can be entered is an example of which type of integrity constraint?

An Operational Constraint

What is meant by program-data dependence?

Any change to a file structure requires changes to the file descriptions for all programs that access the file.

_______________ - a property or characteristic of an entity (a field in a table)

Attribute

A property by which subtype entities inherit values of all attributes and instances of all relationships of their supertype is called ________________.

Attribute inheritance

A _______________ is a primary key that is created by combining two or more fields.

Composite Key

A detailed, technology-independent specification of the overall structure of organizational data is known as _____________.

Conceptual schema

What are the 9 Knowledge Areas of the Project Management Framework and which are the Core and Facilitating functions?

Core Functions: 1. Scope Management 2. Time Management 3. Cost Management 4. Quality Management Facilitating Functions: 5. HR Management 6. Communication Mgt. 7. Risk Management 8. Procurement Management These all go into 9. Project Integration Mgt.

_______________ refers to meaningful facts, text, graphics, images, sound or video segments.

Data

The most common data modeling representation is the _______________ model.

ERD (Entity Relationship Diagram)

This model has resulted from extending the original E-R model with new modeling constructs.

Enhanced entity-relationship (EER) model

______________ is the first step in database development, in which the scope and general contents of organizational databases are specified.

Enterprise data modeling

______________ establish the relationships between entities by means of common fields included in a file, called a relation.

Relational databases

________________- category representing a general link between entities (related tables)

Relationship Relationship instance - specific relationship between entity instances

_______________ is the top-down process of defining one or more subtypes of a supertype that has already been defined.

Specialization

When transforming an ERD into a table, what does a Binary One-to-Many relationship create?

The Primary Key on the ONE side becomes a FK on the many side (or the PK of the one goes into the many table)

What are the 3 competing demands of a project?

Time, Cost, and Scope must be balanced to meet stakeholder and quality expectations

What are the 2 options for the completeness constraint?

Total Specialization Partial Specialization

This rule specifies that each entity instance of a supertype must be a member of some subtype in the relationship.

Total specialization rule

A rule that cannot be violated by database users is called a ______________.

constraint

The _______________ of a relationship is the number of entity types that participate in the relationship.

degree

A _____________ is a collection of related records.

file

Data are recorded for many customers. Each customer's information is referred to as an ______________ of CUSTOMER.

instance

A __________________ attribute is one that can have multiple values for a single instance of an entity.

multivalued attribute For example, the attribute College Degree might have multiple values for an individual.

A major difference between big data systems compared to both data warehousing and operational, transaction-focused systems is that _______________.

structures of data warehousing are typically expected to be carefully designed before data are stored in them ("schema on write"), whereas many of the big data analytics technologies are intended to be used in the "schema on read" mode (structure of the data and the relationships between the data elements will be determined later, either right before or at the time of the use of the data)

A _______________ is a grouping of the entities in an entity type that is meaningful to the organization. For example, the entity type PERSON is frequently modeled as a supertype.

subtype Subtypes of PERSON may include EMPLOYEE, VOLUNTEER, and CLIENT. Subtypes inherit the attributes and relationships associated with their supertype.

The source of the data (a form of metadata) is sometimes called the _____________.

system of record

a trillion bytes is called a _______________.

terabyte

Structured data is most commonly found in _______________.

traditional databases and data warehouses.

A _______________ entity type is an entity whose existence depends on the existence of a strong entity type.

weak

How does the database approach improve data consistency?

-controlling data redundancy reduces opportunities for inconsistency -you avoid wasting storage space that results from redundant data

What is done in the Conceptual Data Modeling phase of the Database SDLC?

-determine user requirements - determine business rules - build conceptual model (ERD, UML, CASE design)

What are the 5 steps in the systems development life cycle (SDLC) ?

1. Planning 2. Analysis 3. Design 4. Implementation 5. Maintenance

What is meant by planned data redundancy in the database approach?

-integrates previously separate files into a single logical structure -does not eliminate redundancy entirely but allows designer to control type and amount of redundancy

What is done in the Physical DB Design phase of the Databse SDLC?

-select DBMS -Select storage devices -determine access methods -design files and indexes -determine database distribution -specify update strategies -build system **In physical design we decide what database system to use

What is meant by data independence?

-separation of data descriptions (metadata) from the application programs that use the data -data descriptions are stored in a central location called the repository -this allows an organization's data to change and evolve without changing the application programs that process the data.

What are the 2 Requirements of a weak entity?

1. Cannot exist without the strong entity (parent) with which it has a relationship (existence dependency). 2. Has an identifier that is derived from the parent entity in the relationship (identification dependency).

What are the 2 types of constraints?

1. Completeness 2. Disjointness

What are the 3 components of the relational data model?

1. Data Structure -Two-dimensional tables with rows and columns 2. Data Integrity - Business rules to maintain data integrity 3. Data Manipulation - SQL used to manipulate data stored in relations

What are the 9 components of the database environment?

1. Data modeling and design tools 2. Repository 3. DBMS 4. Database 5. Application programs 6. User interface 7. Data and database administrators 8. System developers 9. End users

What are the two important tools to improve data quality with the database approach?

1. Database designers can specify integrity constraints that are enforced by the DBMS. A constraint is a rule that cannot be violated by database users. 2. Clean up (or "scrub") operational data before they are placed in the data warehouse.

What are the 6 steps to the *Database* Systems Development Life Cycle (SDLC) ?

1. Enterprise Data Modeling 2. Conceptual Data Modeling 3. Logical DB Design 4. Physical DB Design 5. DB Implementation 6. DB Maintenance

What are the three main reasons that database applications can be developed faster than conventional file applications?

1. If the database and related applications have already been designed and implemented, the developer can concentrate on functions of new applications and not low-level implementation details. 2. The database management system provides a number of high-level productivity tools, such as forms and report generators, and high-level languages that automate some of the activities of database design and implementation. 3. Significant improvement in application developer productivity is currently being realized through the use of Web services based on the use of standard Internet protocols and a universally accepted data format (XML)

How do we know when to create an associative entity?

1. If we have relationship attribute 2. if many to many 3. I degree is more than 2

What are 5 disadvantages to Database Processing discussed in the slides?

1. New, specialized personnel 2. Cost and Complexity 3. Conversion costs 4. Need for explicit backup 5. Organizational conflict

What are the database development activities during the systems development life cycle (SDLC)?

1. Planning - Enterprise Modeling 2. Planning - Conceptual Data Modeling 3. Analysis - Conceptual Data Modeling 4. Design - Logical Database Design 5. Design - Physical Database Design and Definition 6. Implementation 7. Maintenance

What are 6 advantages to Database Processing discussed in the slides?

1. Program-Data Independence 2. Improved Data Sharing 3. Planned Data Redundancy 4. Improved Data Integrity 5. Faster Application Development 6. Reduced Program Maintenance

What are 5 disadvantages to traditional file processing systems discussed in the slides?

1. Program-data dependence 2. Duplication of data 3. Limited Data Sharing 4. Lengthy development times 5. Excessive program maintenance

What are 3 advantages to file processing systems discussed in the slides?

1. Simple to understand 2. Fast processing times 3. Existing structure (legacy systems)

What are 2 limitations to the database approach?

1. The goal of data independence has proven elusive due to limitations of older data models and database management software. 2. Poor organizational planning and database implementation.

What are the 4 components of the project schedule (Gantt Chart)?

1. Time for each task 2. Logical dependencies between tasks 3. Assignment of personnel to tasks 4. Assignment of resources for each task

What are the 5 basic principles for creating a Work Breakdown Structure?

1. Unit of work should only appear once 2. An item is the responsibility of only one person 3. It must flow and be consistent with how work is actually done 4. Team members should be involved in creating the WBS 5. Items must be specific in terms of work included

What are the 2 forms the Systems Development Life Cycle (SDLC) can take?

1. Waterfall model 2. Rapid Application Development (RAD) Model

What are the 10 steps in project planning?

1. create a project plan 2. create a resource plan 3. create a financial plan 4. create a quality plan 5. create a risk plan 6. create an acceptance plan 7. create a communications plan 8. create a procurement plan 9. contract the suppliers 10. perform phase review

Data management technologies intended for analytics can be divided into what two main categories?

1. data warehousing 2. big data

What are the 5 steps in project initiation?

1. develop a business case 2. undertake a feasibility study 3. establish terms of reference 4. appoint a project team 5. setup a project office 6. perform phase review

What are 5 costs and risks of the database approach?

1. new, specialized personnel 2. installation and management cost and complexity 3. conversion costs 4. need for explicit backup and recovery 5. organizational conflict

5 disadvantages of traditional file processing systems include _____________.

1. program-data dependence 2. duplication of data 3. limited data sharing 4. lengthy development times 5. excessive program maintenance

10 advantages of the database approach include _____________.

1. program-data independence 2. planned data redundancy 3. improved data consistency 4. improved data sharing 5. increased productivity of app development 6. enforcement of standards 7. improved data quality 8. improved data accessibility and responsiveness 9. reduced program maintenance 10. improved decision support

Supertype/subtype relationships should be considered in data modeling with what 2 conditions present?

1. there are attributes that apply to some (but not all) of the instances of an entity type 2. the instances of a subtype participate in a relationship unique to that subtype

_______________ capture the nature of and relationships among data and are used at different levels of abstraction as a database is conceptualized and designed.

Data models

A ________________ is an organized collection of logically related data that includes data and metadata.

Database

A ________________ is a general purpose software system that facilitates the process of defining, creating, using, and maintaining databases.

Database Management System (DBMS)

A ______________ is an application program (or set of related programs) that is used to perform a series of database activities (create, read, update, and delete) on behalf of database users.

Database application

This rule specifies that an instance of a supertype may not simultaneously be a member of two (or more) subtypes.

Disjoint rule

This constraint addresses whether an instance of a supertype may simultaneously be a member of two (or more) subtypes.

Disjointness constraint

What are the 3 types of Integrity Constraints?

Domain Constraint Operational Constraint Referential Integrity

A _______________ is the standard format for displaying project schedule information by listing project activities, resources, and their corresponding start and finish dates in a calendar format

Gantt chart Symbols include: Black diamond: milestones or significant events on a project with zero duration Thick black bars: summary tasks Lighter horizontal bars: tasks Arrows: dependencies between tasks Sub-bars: Baselines

An _______________ is an attribute that uniquely identifies individual instances of an entity type.

Identifier

What is the difference between mandatory and optional relationships?

If minimum is zero, then relationship is optional If minimum is one or more, then relationship is mandatory

How does the database approach reduce program maintenance?

In a database environment, data are more independent of the application programs that use them. Within limits, you can change either the data or the application programs that use the data without necessitating a change in the other factor.

_______________ is data processed to be useful in decision making.

Information

The representation of a database for a particular data management technology is known as ____________.

Logical schema

_______________ are data that describe the properties or characteristics of end-user data and the context of that data. Some of the properties that are typically described include data names, definitions, length (or size), and allowable values.

Metadata also called "data about data"

________________ involves releasing the final deliverables to the customer, handing over project documentation, terminating supplier contracts, releasing project resources and communicating the closure of the project to all stakeholders. The last remaining step is to undertake a Post Implementation Review to quantify the overall success of the project and list any lessons learnt for future projects.

Project Closure

This phase involves the execution of each activity and task listed in the Project Plan. While the activities and tasks are being executed, a series of management processes are undertaken to monitor and control the deliverables being output by the project.

Project Execution This includes the identification of changes, risks and issues, the review of deliverable quality and the measurement of each deliverable being produced against the acceptance criteria. Once all of the deliverables have been produced and the customer has accepted the final solution, the project is ready for closure.

In this phase a business problem (or opportunity) is identified and a business case which provides various solution options is defined. A feasibility study is then conducted to investigate the likelihood of each solution option addressing the business problem and a final recommended solution is put forward. Once the recommended solution is approved, a project is initiated to deliver the approved solution. A 'Terms of Reference' is completed, which outlines the objectives, scope and structure of the new project, and a Project Manager is appointed. The Project Manager begins recruiting a project team and establishes a Project Office environment. Approval is then sought to move into the detailed planning phase.

Project Initiation

This project phase involves the creation of a: ▪ Project Plan ▪ Resource Plan ▪ Financial Plan ▪ Quality Plan ▪ Risk Plan ▪ Acceptance Plan ▪ Communications Plan ▪ Procurement Plan At this point the project has been planned in detail and is ready to be executed.

Project Planning

What is the difference between project buffers and feeding buffers?

Project buffer - time added before the project's due date Feeding buffers - time added before tasks on the critical path

A _______________ is a specific, detailed task to be completed to achieve the related summary task and should start with an actionable verb

Sub-Task

_____________ is an attribute of a supertype whose values determine the target subtype or subtypes.

Subtype discriminator

A _______________ summarizes the subtasks that make it up, and can be a header.

Summary Task

The traditional methodology used to develop, maintain, and replace information systems is known as _______________.

Systems development life cycle (SDLC)

At what point in the *Project life cycle* does the SDLC take place?

The Project Execution phase

When transforming an ERD into a table, what happens to weak entities?

Weak entity becomes a SEPARATE table with a foreign key taken from the strong entity's primary key.

How does the database approach improve accessibility and responsiveness?

With a relational database, end users without programming experience can often retrieve and display data, even when they cross traditional departmental boundaries. Ex. SQL

A ________________ is a constraint that specifies the number of instances of entity B that may (or must) be associated with each instance of entity A.

cardinality constraint Cardinality constraints normally specify the minimum and maximum number of instances. The possible constraints are mandatory one, mandatory many, optional one, optional many, and a specific number. The minimum cardinality constraint is also referred to as the participation constraint. A minimum cardinality of zero specifies optional participation, whereas a minimum cardinality of one specifies mandatory participation.

Managers seek to use knowledge derived from databases for _______________.

competitive advantage

______________ programs are used to create and maintain the database and provide information to users.

computer-based application programs

Stored representations of objects and events that have meaning and importance in the user's environment are known as ________________.

data

A _______________ is an organized collection of logically related data.

database

A ____________is an organized collection of logically related data, usually designed to meet the information needs of multiple users in an organization.

database The repository contains definitions of data, whereas the database contains occurrences of data.

A _____________ is a software system that enables the use of a database approach. The primary purpose is to provide a systematic method of creating, updating, storing, and retrieving the data stored in a database.

database management system (DBMS) -enables end users and application programmers to share data, -enables data to be shared among multiple applications rather than propagated and stored in new files for every new application - provides facilities for controlling data access, enforcing data integrity, managing concurrency control, and restoring a database.

How does the database approach improve decision support?

databases are tailored for different decision support applications

A ______________ attribute is one whose values can be calculated from other attribute values.

derived For example, Average Salary can be calculated from values of Salary for all employees.

A _______________ is a generic entity type that has a relationship with one or more subtypes.

supertype

______________ are persons throughout the organization who add, delete, and modify data in the database and who request or receive information from it.

end users

An _____________ is like a noun in that it describes a person, a place, an object, an event, or a concept in the business environment for which information must be recorded and retained.

entity Examples include customers and orders which are objects that a business maintains information about.

Data that have been processed in such a way as to increase the knowledge of the person who uses the data are known as ____________.

information

The final step in logical database design is to transform the combined and reconciled data specifications into basic, or atomic, elements following well-established rules for well-structured data specifications. For most databases today, these rules come from relational database theory and a process called _______________.

normalization

What are the most important structured data types?

numeric, character, and dates.

One of the most popular RAD methods is ______________, which is an iterative process of systems development in which requirements are converted to a working system that is continually revised through close work between analysts and users.

prototyping

Organizations increasingly use ______________ methods, which follow an iterative process of rapidly repeating analysis, design, and implementation steps until they converge on the system the user wants.

rapid application development (RAD) These RAD methods work best when most of the necessary database structures already exist and hence for systems that primarily retrieve data rather than for those that populate and revise databases.

A _______________ is a database that represents data as a collection of tables in which all data relationships are represented by common values in related tables.

relational database

A ________________ is an association between (or among) entity instances.

relationship instance

A ________________ is a meaningful association between (or among) entity types.

relationship type

A ____________is a centralized knowledge base for all data definitions, data relationships, screen and report formats, and other system components.

repository A repository contains an extended set of metadata important for managing databases as well as other components of an information system.

When the database approach is implemented with full management support, the database administration function should be granted ______________ authority and responsibility for ______________.

single-point authority and enforcing data standards

A ______________ entity type is an entity that has its own identifier and can exist without other entities.

strong

The effectiveness and efficiency of a database is directly associated with the ____________ of the database.

structure

Today, ______________ and _____________ are often combined in the same database to create a true multimedia environment.

structured and unstructured data

A salesperson's database, which would include facts such as customer name, address, and telephone number is an example of _____________.

structured data Structured data are stored in tabular form (in tables, relations, arrays, spreadsheets, and so forth)

A ______________ is a logical description of some portion of the database that is required by a user to perform some task.

user view A user view is often developed by identifying a form or report that the user needs on a regular basis


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