Questions tagged [database-diagrams]
The database-diagrams tag has no usage guidance.
129
questions
1
vote
1answer
50 views
How to represent foreign key in an Extended ER Model in Chen notation?
This is a spin-off of the question at How to represent foreign key in an ER diagram? which is too vague about the needed notation.
There the idea of underlining FKs with a dotted line is stated. I ...
1
vote
0answers
43 views
How is this E-R diagram of an identifying relationship's mapping cardinality correct?
According to textbook Database System Concepts,"The identifying relationship is many-to-one from the weak entity set to the identifying entity set, and the participation of the weak entity set in ...
1
vote
1answer
36 views
Chat/conversation history, entity relationship diagram
Totally aware that there are very similar questions, went through each of them, but those are pretty simple/basic solutions from where i took some things and ideas to create below entity relationship ...
-1
votes
1answer
38 views
Database ER diagram review. Is this a good database design?
I have a task to design an ER diagram and task is given as points below is the description of the problem:
A telecommunications company employs thousands of consultants.
Each consultant is assigned ...
0
votes
0answers
18 views
How can I create a database diagram, showing clearly the FK and PK in SQL Studio 2016?
I would like to know the best way to create a database structure diagram, that shows relationships between certain tables. I am using SSMS 2016.
I tried using "database diagram" option in the SSMS ...
0
votes
1answer
35 views
What is the Relationship between Instagram users and user followers
I'm building a blog project, which each user can follow other users. I'm still figuring out the design and creating the diagrams first. I know that the relationship between users and followers is many ...
1
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0answers
21 views
Carry forwarding token wallet concept [closed]
I'm trying to create a carry-forward wallet system.
Recharge part
I'm developing an app that has the carry forwarding token wallet concept. However, when an user recharge their wallet, an amount of ...
0
votes
0answers
20 views
Strong Relationship Confusion on ER Diagram
In this ER diagram, there's a dashed line between the DAMAGE and RENT entities, signifying a weak relationship. But, as I understand, a weak relationship exists where one entity does not contain a ...
1
vote
1answer
36 views
Database diagram for linked server tables
I run Microsoft SQL Server Express 64-bit version 14.0.2027.2 (X64) on Windows 10 Pro 10.
I created a linked server connecting tables from a Microsoft Access (mdb) database to Server Objects/Linked ...
1
vote
1answer
152 views
ER Diagram Design: Should every entity have a primary key? And can we have sub entity? [closed]
Problem: Design a ER diagram such as:
An item has the attribute: description.
An item can be sold by a company or a person.
A person has the attributes: name, phone and email.
A company has the ...
0
votes
1answer
215 views
ER Diagram about Music Online Store
I am attempting to make an ER diagram where the customer buys music online. We were just in the first weeks of tackling database so a lot of topics isn't introduced yet. Here's what I've done so far:
...
1
vote
1answer
60 views
The best practice for SQL + NoSQL database design [closed]
Iām in process of designing database architecture for my diploma project and I have second thoughts about different solutions.
I know and understand all my objectives can be done within relational ...
0
votes
1answer
31 views
Is it possible to generate DB diagram for all SQL databases opened in SSMS
At the present we have to go to each database and manually generate database diagrams, so I want a way to automate this.
Question: Is it possible to generate DB diagram for all SQL databases opened ...
2
votes
0answers
127 views
PostgreSQL Schema Builder/Diagrams [closed]
I have worked with PostgreSQL, primarily using the Django ORM (started with MySQL and migrated to PostgreSQL) and using pgAdmin for maintenance tasks.
I am now working on an open source project ...
0
votes
1answer
65 views
Can I show a relation - “Either in this table or in that ” in ER diagram?
I am making a database for handling leave applications in an academic institute. Given that there is hierarchy existent in such institutes, and I need to keep record of the people that were at these ...
1
vote
1answer
41 views
Entity Relationship Diagram - Entity depending on attribute
I have an ER-Diagram containing the entity employees. When employees have high skills they may supervise lower skilled employees. How can I model that in an ER-Diagram?
My initial approach of was to ...
0
votes
1answer
36 views
Need help to design ER diagram
I need to design an ER diagram for a centralized healthcare management system for my college mini-project.
Firstly, I came up with the following ER diagram.
ER-diagram-1
While designing the tables ...
0
votes
0answers
56 views
2 Relationships between same 2 entities
New database student here. I am having troubles understanding this case for ER to relational database conversion.
So when mapping this to a database does the table for entity one look like this?
...
2
votes
0answers
60 views
Variable layers of data in a multi-country addresses system
My diagram
I want to record addresses in my database. The layout I have right now is visible in the diagram below:
Considerations
Continent, Country, Subdivision and City will be pre-filled, Address ...
3
votes
1answer
38 views
Setting up relationships on a gaming schema with multiple locales
I've devised the following schema:
Where BotLocale holds locales like en-US, es-AR, etc. GameArtifact has a primary key which is artifact_id and GameClass with locale, identifier being the primary ...
1
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0answers
46 views
Room bookings database - does it make sense to create two tables instead of one column?
There are two types of entities: user and room. A user can
book room
select room
unbook room
unselect room
"Selected room" is a state that indicates when a user has decided to book a room and so he/...
2
votes
2answers
91 views
How to Represent Equation with Variables in Relational Database
I am building an application to store the different formulas used for different subjects in school, and I have drawn the following database diagram to depict that scenario:
I am having trouble ...
0
votes
1answer
30 views
Replacing the removed database diagrams feature [closed]
I have a SQL Server database and want to create an ER diagram for it, to analyze tables and relationships.
The option to create a diagram is no longer present in SSMS 18.
Is there any free tool ...
4
votes
2answers
1k views
What do the entity-relationship diagram (ERD) symbols used in DBeaver mean?
I don't understand the ERDs used by DBeaver. The diamonds and dots at the ends of the line arent the crow's foot I'm used to. I've googled the subject and checked the docs but can't find a straight-...
1
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0answers
1k views
Crow's foot notation--what is the difference between “one” and “one-and-only-one” regarding relationship cardinalities?
I'm trying to figure out the difference between the single-bar and double-bar cardinality indicators as in the figure below:
Some sources seem to use one notation while others use the other. I can't ...
1
vote
2answers
191 views
Error 1005 when Forward Engineering EER diagram
I have created an EER diagram (as shown in the image bellow) in MySQL Workbench and wanted to Forward Engineer to build the DB.
After configuring the model options to the Target MySQL Version and ...
0
votes
0answers
92 views
Modelling Orders and Messages for an e-Commerce database
In my e-commerce application I would like that buyers and sellers interact via a messaging system to purchase products.
The process consists of:
The buyer inquiring for a product
The seller responds ...
1
vote
1answer
703 views
How to create a correct entity-relationship diagram (ERD) about a video game profits scenario
I'm starting to build my application database, and I'm really new to the this world, so I have a lot of doubts about my ERD and if its entity types and relationships are ok.
This is an application ...
0
votes
1answer
476 views
Modelling products along with their attributes and discounts for an e-Commerce database
Scenario
My application will have products belonging to 1 company. Each of those products will:
Have at least 1 quantity
Have 0 or more discounts
Have 1 or more attributes
Belong to 1 category, which ...
1
vote
1answer
114 views
SQL Server Database Diagram
I am using SSMS v18, I need to create an ER diagram from my database. As Microsoft removed diagram from new version of SSMS (v18) so now How can I get a diagram for my database??
0
votes
1answer
28 views
Is there a place to store ERDs in Postgres?
Is there a designated spot in Postgres to store Entity-Relationship Diagrams (ERDs)?
I could just create a table with a BTYEA column or something, but I want to make sure to use what exists if ...
2
votes
2answers
221 views
Does the relationship between teams and matches have a many-to-many cardinality ratio?
Diagram
I created the following diagram:
Considerations
So I will create two tables, one called Match and the other one called Teams. In Match there will be data about two teams, Away and Home.
Let ...
1
vote
1answer
39 views
How to avoid losing information via UPDATEs due to database design issues
Business requirements
I have a database where information about documents and their related packages are kept. Each document can have multiple packages, and each package has its details and product ...
1
vote
1answer
2k views
Is it possible to change the color of relationship lines in MySQL Workbench diagrams?
I have MySQL Workbench Community Edition 8.0.15 installed on my Mac OS 10.14.3. I'm currently working on making an ERD with Workbench's EER Diagram.
My problem is that whenever I export my diagram, ...
0
votes
1answer
62 views
Creating and querying a database to set hierarchical associations between Groups, Users, Items and Points
I am working with three entity types, Group, User and Item. A Group consists of Users, and a User consists of Items.
Now, I have to work with a fourth entity type: Point. I want to be able to ...
0
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0answers
189 views
Multiple tables for different types of transactions?
Considering a trading system as an example. Would it make sense to have two different tables for credit transactions and asset transactions?
creditTrans : table
id
userId
transType
status
amount
...
0
votes
1answer
425 views
How to maintain customer addresses for Orders?
The database I am designing is part of a project I am working on. I have come up with 3 simple "business rules":
Customers must either be Individuals or Businesses (a business belongs to a certain ...
1
vote
0answers
585 views
Gaming shop database schema
I'm trying to design schema for my personal project that would be an online gaming shop. I would like to ask you guys for any suggestions/tips on how could I maybe improve my current draft.
Concerns:
...
2
votes
0answers
202 views
Modelling a database for a simple IT device tracking scenario
Sorry, my English is not that good.
I need a simple IT device tracking sytem at work.
For each device I need to know its current location, status and ownership (employee to which it is assigned).
...
1
vote
0answers
266 views
Modelling an entity-relationship diagram for a scenario involving companies, services, and clients
I am creating an entity-relationship diagram (ERD) for managing workflow and other details of Company X in which I am maintaining details of the following objects:
Employees of Company X
Services ...
1
vote
0answers
83 views
Creating an entity-relationship diagram about an art fairs and galleries business environment
Scenario description
The charactheristics of the business domain under consideration are:
Each and every art item has a unique identifying number, and also a name and asking price.
Art galleries ...
2
votes
1answer
1k views
Do you know if this are examples of non-identifying or identifying relationships?
Im using MySQLWorkbench to model a diagram. But Im with some doubts about identifying and non-identifying relationships. It seems that all relationships of the project are identifying.
For example, a ...
-1
votes
2answers
96 views
payment table in relational datase
I have to model a database table for payments. These need to have two fields payment from and payment to and this needs to link to two tables one is clientA and clientB as in the representation below. ...
1
vote
1answer
28 views
How to express a “some of which are” and “not all are” relationship with enhanced entity-relationship diagrams?
For example:
Gardens have attribute gate, Condos have attribute door. Some of the Gardens and Condos are Private_Properties. On the other hand, Private_Properties are not restricted to only Gardens ...
0
votes
1answer
2k views
MySQL WorkBench SQL : Cannot Add Foreign Key Constraint (Error 1215) while creating database
Problem:
I am receiving the
Error 1215: Cannot add foreign key constraint
error while running my MySQL schema code generated from the EER Diagram I used to model my database.
The Error occurs ...
1
vote
1answer
1k views
How do I change where database diagram relationship lines attach in MySQL Workbench?
Sometimes, MySQL Workbench makes some strange choices about where table relationship lines get attached. For example, two vertical lines would be better in the following:
For a while, these boxes (...
1
vote
1answer
142 views
Representing a many-to-one relationship in a database diagram
I have two tables loadingDetail, and stowageDetail:
loadingDetail | stowageDetail
[PK] loadingID (int) | [PK] StowageID (int)
[PK] transactionID (in) | [PK] room (int)
...
2
votes
1answer
286 views
Scripting Creation Of Database Diagrams
Is it possible to script the creation of a database diagram using T-SQL?
If not, what is the Database Diagram Designer doing when you use it to save / edit a diagram (is it using PowerShell or some ...
1
vote
0answers
273 views
Basic ERD analysis for a martial arts business domain
I am working on a basic website in order to support querying results from martial arts tournament data. We use participation data to determine things like who gets to host tournaments, regional awards,...
0
votes
0answers
64 views
Issue with diagrams in sql management studio 2014
I have this issue with sql management studio 2014.
When creating a new database diagram and when I add existing table to a new diagram, the data inside a table is obsolete. I tried both dragging a ...
