Analysis Phase Flashcards
The analysis phase involves converting the ____________specification into a __________ specification.
requirements, problem
What are the three modeling techniques?
data modeling, process modeling, or object-oriented modeling
What are the major inputs and outputs of the analysis phase?
Input: Reqmts. specification
Output: Problem specification and System proposal
Along with system models and flowcharts what are 4 more of the principal tools in the Analysis phase?
Data dictionary
data flow diagrams
data models
prototyping
The components of a structured analysis include no only the context and dfd diagrams, but also what?
state diagrams, process specifications and data dictionary.
The data flows in dfds are physical and logical. T or F
F. Only logical.
External entities can represent what?
Human, subsystem or system.
In a dfd, what is a process?
Business activity/function where the manipulation and transformation of data takes place.
In a dfd, what is a data store?
storage of persistent data that is required for or produced by a process.
Rule1- Data stores must have what at least?
1 incoming data flow and 1 outgoing.
Rule2-how many incoming and outgoing data flows can one have ?
Many.
Rule3-A process can connect to which symbols?
Any, including another process.
Rule4-A data flow leaving a process is always named what?
Something different then when it came in.
Naming conventions for:
a. ) Process
b. ) Data Store
c. ) Source/Sink External entity
a. ) Verb-Adj-Verb
b. ) Noun, describing data
c. ) Noun
d. ) Descriptive noun
Rule5-When is a data store required?
When processes share data.
If output is not immediately needed by the next process, what is used and why?
A data store so that it can synchronize the process.
How does an external entity interact with the system?
By either sending the system data or receiving it.
Rule6-When is a double arrow used?
When a process is reading data and updating the data on the same table or file (i.e. data store.). A read before an update.
A context diagram contains all the external entities and what else?
The major data flows to and from them.
Diagram 0 dives into the context process (or the system itself) and should always include what?
External entities, the major processes w/in the system and major data stores.
What is a primitive process?
One without a child diagram.
A top-down approach to a dfd first includes what, then ends with what?
Listing business activities to elaborate on dfd factors (ext. entities, data flows, etc…)
Partition physical dfd to facilitate implementation.
when making a physical dfd out of the logical dfd, one must distinguish between what type of processes?
Manual and automated.
Throughout each level of the dfd, this must remain constant?
Inputs and outputs.