is202 exam3 practice questions

A data flow diagram(DFD) is ___________________ and shows______________

a graphical representation of the flow of data internally within a system

how data moves from input sources through various process to output destinations

Describe input data

data flow coming into the process

Describe output data

data flow leaving from the process

An example of a Process could be:

Described as a Verbs— Create, Define, Produce, Return, Divide

An example of Data Flow could be

Described as nouns— Ingredients, Grocery List, Patient Info

An example of a Data Store could be:

Inventories of Data— Patient Portal, HRIS, Insurance Records

An example of an Entity could be:

provides or receives data in the system— Chef, Patient, Physician, HR Manager

Which is the correct order for developing DFD diagrams?

Make a list of [entities, data flows, processes, and data stores], decomp diagram, context diagram, level 0 DFD, level 1 DFD, correct errors, logical DFD>> physical DFD

Context Diagram contains_________

only one process representing the entire system

How are diagrams labeled on Data Flow Diagrams?

starting with 0 on the context diagram process, then each process is numbered on level 0,then each child diagram subprocess is labeled with an decimal point

A level 0 DFD is called a___________ and a level 1 DFD is called a ____________.

parent, child

A level 0 DFD is__________

an explosion of the context diagram looking at the details of the root process

_______ and _________ from previous diagram should remain the same

inputs, outputs

what’s the primary rule of Level 1 DFD

vertical balancing——dictates that a child diagram cannot produce an output or receive an input that the parent diagram does not produce or receive

What’s something that can be excluded from Level 1 DFD/ child diagrams?

entities aren’t usually shown

Child diagram may have_______ not shown on parent diagram

data stores

processes not exploded/ not detailed are described as what?

functionally primitive— known as primitive processes

Difference between logical DFD and Physical DFD

logical DFD focuses on business operations, physical shows how the system will be implemented

Common Errors involving data flow

forgetting to include data flow/ pointing an arrow in the wrong direction

incorrectly labeling data flow

omitting data flow

Errors is Data Flow——What is Linear Data flow?

data flow with only one input and one output

Common errors involving Entities

connecting entities and data stores directly to each other, rather than through a process

common errors with processes

incorrectly labeling processes

using too many processes— more than 9 causes miscommunication

How to prevent unbalanced explosions?

each child diagram should have the same inputs and outputs as parent processes