But you learn once and program for a long time, so that ease of learning is of only limited value.
N-S diagrams are an alternative to pseudocode. N-S diagrams show processing by series, by selection, or by iteration. N-S diagrams are read from top to bottom.
N-S diagrams are more structured than flowcharting one start, one end. Entity Relationship Diagrams As the name describes, an entity-relationship diagram ERD is used to model the entities that a computer system records information about, and the relationships between those entities.
The evolution of an ERD typically progresses either from scratch through an interview process or is reverse-engineered from an existing database schema. Bachman Many developers and CASE tools still use Bachman's crow-foot notation [ 10 ] to indicate the cardinality of a relationship.
Where necessary, a relationship type is often written on or near the line that represents a relationship. While the traditional aspects of entities and relationships are represented as boxes and lines respectivelythere are a number of unique attributes to his present method [ 4 ]: The cloud symbol represents aggregations of smaller ER diagrams, in the context of a logical design as opposed to a physical design.
The double-box represents a weak entity, which is dependent on its parent entity. Visio does not support this feature. A diamond symbol represents a type of relationship. Relationship adornments are added adjacent to the lines to indicate connectivity I, M, N and cardinality, e.
The data-structure diagram an alternate form of the ERD uses arrows to show I: Circles represent the attributes of an entity, although Visio labels this icon as value. A human figure represents a user icon.
James Martin Visio's Martin ERD template is based on the symbols used in the Martin notation [ 9 ] to draw object-oriented analysis and design diagrams.
This notation has the following attributes: Rectangles and ovals represent entities and attributes or data itemsas with Chen's notation. A line with a midpoint arrow indicates a message or data-flow. A rounded rectangle represents activity.
A large arrow represents an event. A triangle with a numeric label represents a connection. A diagram that uses all of these notation elements simultaneously can be very elaborate and potentially confusing.
By conventional techniques, an ERD will only contain entity, data item, and relationship symbols, while the remaining elements especially activity and event items usually appear in an object diagram.
Data Flow Diagrams The formal, structured analysis approach employs the data-flow diagram DFD to assist in the functional decomposition process. I learned structured analysis techniques from DeMarco [ 7 ], and those techniques are representative of present conventions.This handout will help you determine if an assignment is asking for comparing and contrasting, generate similarities and differences, and decide a focus.
develop a thesis that goes beyond “Thing A and Thing B are similar in many ways but different in others.” noticing the language that is used to ask for the comparison/contrast and. compare is used for showing the likenesses between two or more things.
Compare these sofas for size and comfort. contrast is used for showing the differences and especially the . The question on comparing writing techniques. There are three steps to answering this question. You need to identify writing techniques used in a text.
Compare the ways in which Shakespeare and Marvell have used poetic form, structure and language to present their thoughts and feelings of love.
Compare the ways language is used in source three and source two Essay. Source two uses formal language so that it can fulfil its purpose to inform the audience - Compare the ways language is used in source three and source two Essay introduction.
Therefore it uses facts and figures throughout the article to give the reader as much information as possible whilst still containing the sense of. Comparison of Diagramming Methods. When it comes to recording the results of a system analysis, there are so many diagramming tools and methods available that it can be difficult deciding which one to use.