
Case "Designing a web service for booking tickets." Business analysis. Domain Description
In parallel with the description of business processes , the context and profiles of stakeholders, it is necessary to study the subject area. The main tools here are a glossary of terms (which is best compiled with an expert in the subject area) and an entity diagram that shows which entities are and what are the relationships between them.
- The viewer must be over 14 years old (for businessability).
- An additional user agreement is required in which the user will need to give consent to the use of his personal data.
- The agreement should also indicate that the reservation service is provided free of charge.
Do not confuse an entity diagram with a logical data model! It is created at the so-called conceptual level, it does not intentionally indicate entity attributes, and the entities themselves are not the final option for storing information in a database; on the contrary, this diagram provides the basis for compiling a logical data model.

Entity attributes will be described in the product analysis phase in the data dictionary.
After the basic entities are defined, it is necessary to describe their life cycles. In this case, it is told what happens to the ticket and movie show, what are the main conditions they go through. How is the transition from one state to another? Transitions in the future will become the basis for writing options for using the system (which will appear in the technical phase of analysis and design).


Everything that is difficult to express using the described tools is desirable to fix in the form of atomic requirements - expressions that reveal what restrictions exist in a given subject area.
BR-1 - If the reservation was not redeemed in 20 minutes. before the session, it is removed.
BR-2 - You cannot book a ticket in less than 20 minutes. before the session.
BR-3 - You cannot book more than 5 tickets at the same time for one or more sessions.
BR-4 - You can only book tickets for Movie Shows, which will be shown in the next 2 days and approved for showing on the Cinema’s schedule.
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IV. Domain Description
Legal restrictions
- The viewer must be over 14 years old (for businessability).
- An additional user agreement is required in which the user will need to give consent to the use of his personal data.
- The agreement should also indicate that the reservation service is provided free of charge.
Glossary of Terms
Entity diagram
Do not confuse an entity diagram with a logical data model! It is created at the so-called conceptual level, it does not intentionally indicate entity attributes, and the entities themselves are not the final option for storing information in a database; on the contrary, this diagram provides the basis for compiling a logical data model.

Entity attributes will be described in the product analysis phase in the data dictionary.
State diagrams of key entities
After the basic entities are defined, it is necessary to describe their life cycles. In this case, it is told what happens to the ticket and movie show, what are the main conditions they go through. How is the transition from one state to another? Transitions in the future will become the basis for writing options for using the system (which will appear in the technical phase of analysis and design).
Life Cycle

Ticket Life Cycle

Domain Business Rules
Everything that is difficult to express using the described tools is desirable to fix in the form of atomic requirements - expressions that reveal what restrictions exist in a given subject area.
BR-1 - If the reservation was not redeemed in 20 minutes. before the session, it is removed.
BR-2 - You cannot book a ticket in less than 20 minutes. before the session.
BR-3 - You cannot book more than 5 tickets at the same time for one or more sessions.
BR-4 - You can only book tickets for Movie Shows, which will be shown in the next 2 days and approved for showing on the Cinema’s schedule.
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