Chapter 14 : Deploying the New System

System Analysis and Design John Saztinger, Robert Jackson, Stephen Burd

the process of examining a component, subsystem, or system to determine its operational characteristics and whether it contains any defects

Testing

a formal description of a starting state, one or more events to which the software must respond, and the expected response or ending state

-Defined based on well understood functional and non-functional requirements

-Must test all normal and exception situation

Test Case

a set of starting states and events used to test a module, group of modules, or entire system

Test Data

Software components must perform to the defined requirements and specifications when tested in isolation. What type of testing is that?

Unit testing

Software components that perform correctly in isolation must also perform correctly when executed in combination with other components in the new system. What type of testing is that?

Integration testing

What is an example of an Unit test?

incorrectly calculates sales tax amounts in different locations

What is an example of an integration test?

sales tax component that calculates incorrectly when receiving money

A system or subsystem must meet both functional and non-functional requirements. What type of testing is it?

System and stress testing

Software must not only operate correctly but must also satisfy the business need and meet all user “ease of use” and “completeness” requirements. What type of testing is it?

User acceptance testing

What is an example of system of stress testing?

item looks up function in a sales subsystems retrieves data within 2 secs when running in isolation, requires 30 secs while running the system

What is an example of User acceptance testing?

a commission system that fails to handle special promotions or a data-entry function with a poorly designed sequence of forms.

tests of an individual method, class, or component before it is integrated with other software

Unit test

a method or class developed for unit testing that simulates the behavior of a method that sends a message to the method being tested

Driver

a method or class developed for unit testing that simulates the behavior of a method invoked that hasn’t yet been written

Stub

one method passes a parameter of the wrong data type to another method

Interface incompatibility

A method is passed or returns a value that was unexpected, such as a negative number for a price

Parameter Values

A method generates an error, such as “out of memory” or “file already in use,” due to conflicting resource needs

Run-times exceptions

The states of two or more objects interact to cause complex failures, as when an OnlineCart class method operates correctly for all possible Customer object states except one

Unexpected state interactions

What is the required procedure for create test data?

comprehensive test data, must be coordinated between developers

What is the required procedure for conduct the integration test?

Assign resources and responsibilities. Plan frequency and procedures

What is the required procedure for evaluating the test results?

identify and valid and invalid respones

What is the required procedure for creating test suites?

Build and unit test the components to be integrated

What is the required procedure for logging test results?

Log valid test runs. 

log errors

Correct the code and retest

an integration test of an entire system or independent subsystem

System Test

a system test that is performed daily or several times a week

Build and smoke test

an integration and usability test that determines whether a system or subsystem can meet time-based performance criteria

Performance or stress test

the desired or maximum allowable time limit for software response to a query or update

Response time

the desired or minimum number of queries and transactions that must be processed per minute or hour

Throughput

a system test performed to determine whether the system fulfills user requirements

User acceptance test

What is UAT stand for?

User Acceptance test

How to plan the UAT?

-Should be done early in the project

-Test cases for every use case and user stories

-Identify conditions to verify that the system supports the use case accurately and completely

data entry and database records

Develop test data

system tests, stress tests, and user acceptance tests are considered deployment

Note

requires a fully populated database to support ongoing processing

operational system

Modify or update existing data

Reuse existing databases

Copy and convert the data

Export and import data from distinct DBMSs

Data entry from paper documents

Reload databases

Training is needed for

end users and system operators

Large organization train _______ who in turn end users

trainers

Descriptions of system requirements and architecture to help maintenance and upgrade of the system

System Documentation

How to interact with and use the system for end users and system operators

User documentation

Which specific type of development order implements top-level modules first (use stubs for testing)?

Top-down development

What specific development order that implements low-level detailed modules first (use drivers for testing)?

Bottom-up development

What is IPO stand for?

input, process, output

a development order that implements input modules first, process modules next, and output modules last

input, process, output

select specific use cases and order the development based on selected use cases

Use case driven

An automated tool for tracking source code files and controlling changes to those files

source code control

What is SSC stand for?

Source Code Control

What is an example of a source code control?

When a programmer needs to make changes to a file, he or she checks out the file in read/write mode

The _______ allows only one programmer at a time to check out a file in a read/write mode

SCCS (SSC system)

What are three different approaches?

Direct deployment

Parallel deployment

Phased deployment

a deployment method that installs a new system, quickly makes it operational, and immediately turns off any overlapping systems (higher risk, lower cost)

Direct deployment

a deployment method that operates the old and the new systems for an extended time period (lower risk higher cost)

Parallel Deployment

deployment method that installs a new system and makes it operational in a series of steps or phases

Phased Deployment

tools and processes handle the complexity associated with testing and supporting a system through multiple versions

Change and Version Control

a test version that is incomplete but ready for some level of rigorous integration or usability testing

Alpha Version

a test version that is stable enough to be tested by end users over an extended period of time

Beta Version

a system version that is formally distributed to users or made operational for long-term use

Production version, release version, or production release

a system update that provides bug fixes and small changes to existing features

Maintenance release

Deploy in two versions

Phased Deployment to Minimize Risk

New database built and data migrated before deploying version 1, in iterations

Database Development and Data Conversion

Start with the higher risk Sales subsystem and customer facing Order fulfillment subsystem

Development Order

Spread throughout later iterations for both versions

Documentation and Training

control systems enable development teams to coordinate their work

Source code

improves post deployment support by enabling developers to track problem support to specific system versions

Versioning