vb.net computer room Charge System reconstruction--Summary (iii) Software engineering documentation 2

on article written to the requirements of the prospectus to be included in the IPO map, specifically what is the IPO map, I have a detailed understanding of a bit.

IPO refers to the input, processing (processing) and output (outputs) of a transformed structure in a structured design. is a detailed detailed design tool for each module.

To put it bluntly, the IPO diagram is about the input, output, and data processing.

Here's an example of landing:

During the login process, the data entered is the user name and password. Processing: Check the user name, password each content. Output the main form. This is the IPO map of the landing.

In the requirements manual can also be simple to draw the entity-Relationship diagram (entity--relationship), because in the database design instructions also exist in this diagram, there is no more to say.

The above is the software requirements documentation.

(iii) database design manual

The most important part of the database design manual is to write clearly the conventions for naming the database as

The most important is the E-r diagram and each table details

Here I use Edraw software.

A real e-r diagram should be there is no many-to-many relationship, and a one-to-one relationship, such as students and cards, this relationship I said before, some people think that must be completely in accordance with the three paradigms, but specific business specific analysis, sometimes in order to improve query efficiency, allow certain data redundancy exists. In this system, it is perfectly possible to merge the card and student tables into one to improve query efficiency. Therefore, student entities and card entities can be reported to be merged together.

After drawing the E-r diagram, there are detailed information about each entity, taking the student entity as an example

There is also a data graph for database conversions.

Finally, there is a design of each table, taking the student table as an example.

List the stored procedures that are used

Finally, the main content is the data dictionary

First explain what is a data dictionary: Baidu Encyclopedia explained that : Data dictionary refers to data items, data structure, data flow, data storage, processing logic, external entities, such as the definition and description, the purpose is to make a detailed description of the various elements of the data flow diagram.

It sounds like a heavenly book, and it's only two points to tidy up.

1) The Data dictionary holds information about the database and is a set of read-only tables for the user.

2) The composition of the Data dictionary:
1. Data item
2. Data structure
3. Data Flow
4. Data storage
5. Processing process
Take my data dictionary, for example, to intercept only a subset of

Then a description of the data item

In my database design manual, the data dictionary mainly consists of these two parts, if there are shortcomings, please point out.

The above is the main content of database design

vb.net computer room Charge System reconstruction--Summary (iii) Software engineering documentation 2