Wagby's design focuses on "data". Specifically, it is the entrance to the design to organize the structure of business data. This is called modeling.

Wagby organizes the design information of the business application from the viewpoint of "structure" and "behavior".

Construction

Describing static matters.The core is "model" (data storage unit) and "relationship" between models.

One model contains several model items.Model items are related to other models, and some are derived by formulas.

The model is a view from the point of view of business, but in many cases it needs to be perpetuated.Since Wagby uses a relational database for persistence, model definitions eventually lead to table definitions.

Behavior

Describing dynamic matters.Includes input rules and transaction processing (processing to update multiple models at the same time), screen transition and access control by authority.

The usability of the screen operation viewed from the user is also regarded as behavior.

Wagby treats "structure" as the basis in the "structure" and "behavior" categories.That is, the starting point of the design is the definition of the model.This way of thinking is commonly known as "Data Oriented Approach (DOA)".

"Model" is a semantic unit for storing data.Due to its nature, the model can be classified as shown in Fig.

Figure 1 Rough properties of the model

Choice

From "simple" such as "male" and "female", such as industry type code and slip type.Code design is done based on business rules, but usually code values ​​(once decided) are not changed.The content part (character string) corresponding to the code may be changed.

Also, as a matter of choice, it never removes the assigned code once.This is because all other data that referenced the code will be affected if it is deleted.Therefore, instead of physical deletion, logical deletion (records are kept in the database but invisible from the application) is used.

Wagby supports logical deletion with all model reference relations including options.

Master system

Also called "resource".It is necessary data to be registered beforehand when the system is in operation.For example, there is a product master and a customer master.

For preliminary registration of master data, it is convenient to input by Excel etc, upload it to the system and register it all at once.Wagby is "Upload updateIt is realized by the function called "

Transaction system

Also called "event".It is data that is registered, updated and accumulated by daily work.Wagby expresses both the master system and the transaction system by "model".

We will organize the model we picked up from the viewpoint of data registration method this time.As shown in Fig. 2, there are approaches such as "input from the screen", "collective registration from CSV, Excel", "import from the backbone", "cooperation with another system" and "preset".

Fig. 2 Organization of data registration method to model

Of these, "import from core systems" and "cooperation with other systems" are not supported by the Wagby standard function.You can use these tools by dedicated tools or by creating batch programs separately.

The advantage of Wagby is that all the tables (on the relational database) corresponding to the model are created automatically, and the structure is made clear so that it can be accessed from the outside.Therefore, you can register, update and view data using various methods including existing tools.

Care must be taken when providing multiple registration / update methods for one model.In WagbyAt the time of updating (to prevent data from being destroyed due to conflicts) lock it.Ignoring this lock and updating the same data from the outside will cause inconsistencies.For this reason we will adapt Wagby's locking rule for the whole application.Alternatively, you can set the Wagby side model to read only, synchronize at fixed time intervals.
In the case of newly developed projects, please skip this explanation.

Wagby prepares a table definition statement (create table) based on the design information of the defined model.However, if you already have an existing table, you can reuse the existing table by designing the model according to this structure.

In Wagby, you can specify the table name for the model and the item name / type of the table for the model item individually.By specifying these in the repository (design information), it is possible to utilize existing tables.

important point

Although the backbone system is already running, there are cases where you want to wagby a subset of them.The way to reuse the existing table depends on each case.I will organize representative notes.

  • In Wagby you want to treat it as "date type", but in the existing table it is an 8-digit string of yyyyMMdd, so the type may be different.A simple way to solve this is to define a "view" in the database.From Wagby let's manipulate the view (not the table) and ensure consistency with the existing table on the view side.
  • Wagby's model design automatically generates the third normal table structure.For example, item information (repeating container) is a separate table linked by keys.However, if the existing table does not have such a structure and holds data as an occurrence (for example, telephone number 1, telephone number 2 are defined as items and the third phone number can not be managed) It is still necessary to devise.
For specific approaches and design guidelines, please contact Wagby Reseller.

In individual model definitions, what matters is the design of "primary key" (to identify itself). The primary key in Wagby has the following properties.

  • The primary key must not be duplicated.It must be unique.
  • Once assigned the primary key, it can not be changed.

The design of the primary key will be done from the viewpoint of whether to give meaning to the value of the key (artificial key or natural key), and whether to use a single item as a key or a compound key.

Although the criteria of design varies depending on business requirements, from a system viewpoint, a single item artificial key (so-called sequential method) is the simplest and easy to handle.Therefore, we recommend first considering whether it can not handle with artificial keys first.

We organize the relationships of the models where we have sorted out so far.Express each model with a structure called "ER diagram" (Entity-Relationship).

Figure 3 Example of ER diagram

However, Wagby can specify not only a static structure but also "how to operate associations on the screen".List box, radio button, check box, search screen etc.Also, since there are functions of reference interlocking and narrowing down, it is better to arrange the reference method in such a way as to memorize it in the ER diagram.

Before organizing the relationship of models,"Reference other models" function provided by WagbyIt is recommended that you learn the overview of.
Wagby does not include ER drafting tool.Since there are various tools in the market, please use these to organize the relationship.(In a small-scale system, you can grasp even using paper.)

At the timing when you can grasp the relationship between models, try to register design information using Wagby Designer for some models.

In this stage, calculation formula, screen layout, user's authority, etc. are not fixed.These may be postponed.

The aim here is to wake up an application that works from the structure of the model at an early stage and review whether there is something to add to the model item and whether the relationship between the models is appropriate.

Instead of aiming at the perfect application from the beginning, please build with the intention of checking the design information (but reviewing using a running application, not a static review) at this stage.

We will review the build application with stakeholders.At this time, the timing at which the 'person in charge of the field who actually operates the application' is added depends on each project.Please judge by project leader.

Again, the goal of the review at this stage is to verify "have not forgotten models or model items".The discussion will diverge when talking to ease of use and the color of letters here.Project leaders should instruct them to review with awareness of the goals at the moment.

Wagby's skills required to do so far are as follows

You do not need to grasp all the functions (manual) of Wagby at the same time.First from "Structure Definition"I will proceed.

In the next chapter we will deal with "calculation formula" which is another aspect of structure.