Entity Relationship Diagram

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3
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1answer
30 views

Store the content book in database, so that it would be updated afterwards or store them as document?

I have some books in (urdu) made with Urdu Inpage(tool for making pages in urdu) like this: problem that these document files are difficult to read in php because they gives unread-able characters, ...
3
votes
1answer
24 views

How to represent the optionality of a many-to-one mandatory relationship from the Parent to its two Child entity types in an ERD?

I have a Parent entity type with two Child entities, with a relationship cardinality of many-to-one (or M:1) from Parent to Child. The business rules say that: It is mandatory that the Parent ...
1
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0answers
38 views

Ternary relationship with history tracking

I have the following entities Procedure -> id_procedure , desc_procedure . Status -> id_status , desc_status . Subprocess -> id_subprocess , desc_process . The rules are: 1 ...
1
vote
1answer
33 views

relation between customer and product with review

I draw this ERD but I'm not sure if the relation in customer and product with review is correct. also, is it right that I made Rate, Date and time this way ? this is my Description for review Each ...
2
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0answers
38 views

ERD to SQL Server

I am working on an assignment and am having one heck of a time getting my head wrapped around these questions. I need to be able to write in SQL Server 2014 certain select statements based solely off ...
1
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0answers
34 views

Handling Strong and Weak entity types in a one-to-one relationship

I am modelling a database for a term project and I have come across something I do not have a definite answer to. Diagram I was supplied with the following Entity-Relationship diagram: ...
0
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1answer
45 views

Should a TeamMembers table have a relationship with the Student Table or the Enrolment Table?

I'll keep it nice and short and simply link to the ERD: Users can be assigned a role, one of those is student. So for the sake of this, Students are the same as Users! A Student can be enrolled in ...
0
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0answers
20 views

What is the correct database design for accommodating a request and a receive transactions?

In my project management system, I have a feature that requests a rental from a supplier. Once the set of equipment arrives, I can now create a rental receive to monitor the equipment inventory which ...
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0answers
9 views

Database ERD for orders info

I have two tables: 1-orders order_id 2-shipping_and_billing order_id FK address_type(billing and shipping ) city I need to get full info of shipping and billing in single select of ...
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0answers
13 views

Entity–relationship model and relational model

Entity–relationship model is conceptual model... it defines the conceptual view of a database. It works around real-world entities and the associations among them it is implemented in a ...
4
votes
1answer
51 views

Visualizing Database Schema [closed]

I am not a DBA, but an end user that mashes together data from various databases within my company to generate insights. When I first encounter a new (to me) database, I spend time scrolling ...
1
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1answer
52 views

Normalizing data for joins, dedicated columns, a view or.. something else? [closed]

As an example, i have the following tables USERS, USER_JOBS and USER_HOUSES USER_JOBS keeps a list of jobs for a given user_id USER_HOUSES keeps a list of houses for a given user_id the common use ...
0
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2answers
41 views

Modeling a product database and dealing with inheritance

So, to get better at designing databases, I'm attempting to model a database system after the AR15 Builder. Here is what I have so far: While it makes sense logically, I'm afraid there may be ...
4
votes
3answers
74 views

What's the point of the relationship diamond in Entity-Relationship diagrams?

I'm drawing an ER diagram for an ecommerce site that I'm building, and noticed something: the diamond that I am drawing between two models (or entities), which I understand is meant to symbolize the ...
3
votes
2answers
79 views

How do I read ERD Notation (crow's feet) to convert to Natural Language?

Background I am attempting to insure I understand how to read ERD (Entity Relationship Diagram) notation so I can convert it to a natural language explanation. I'm trying to insure I can explain a ...
0
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0answers
37 views

Are my two proposed solutions on modelling resources inventory decent?

In the project management system that I am developing, I am wondering what is the best database design for keeping track of the resources inventory. While I want to determine what resources are ...
3
votes
4answers
108 views

In a one-to-one relationship, where should the foreign key be placed?

I am currently designing an ERD for a project management system. I am unable to choose between two workable solutions as the best solution as I wish to embrace the best standards. The two entities ...
3
votes
2answers
122 views

Survey Database - Respondent Table (1NF or 3NF - Pros and Cons)

Building out a Survey ERD ODS layer. Now i'm debating on the design for my Respondent Table. Not sure if its best to have it as 1NF or 3NF. FOr a quick back story I get a survey extract with ...
3
votes
2answers
57 views

Is it possible to display this restriction in an ER diagram?

I have a question about modeling a particular kind of restriction, but I don't know the technical term for it, so I will illustrate it with an example. I wish to make an ER diagram for a hotel room ...
0
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0answers
13 views

Difference between has and contains in ERD diagram [duplicate]

I am working on an ERD which represents the relationships between entities in a Web development company behavioral model. There I have entities like: Customer Service ----------- (like: web ...
5
votes
1answer
174 views

ERD for a web development company

I am working on an ERD which represents the relationships between entities in a Web development company behavioral model. There I have entities like: Customer Service ----------- (like: web ...
1
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0answers
61 views

ERD Diagram based on Crow's Foot model for Milky Way Jewelry

this was on my final exam this past winter exam season, in search for the answer since i got it wrong: Draw an ERD diagram based on the Crow's Foot model for a database to support the basic ...
1
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0answers
93 views

What is a good database design approach for my Online Quiz Android Application?

I have been working on an Android Online Quiz Application with PHP & MySQL. I know what attributes i need however when designing the relationship it becomes complex and confusing when I analysed ...
0
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0answers
13 views

ERD question, problem with connecting

So I have a question involving an assignment i got. The question is I can see out of a query the total amount of days a room was occupied. However I think my Reservations and Rooms should be many to ...
1
vote
1answer
52 views

ERD to Relational schema

I'm new to DBM and I'm trying to learn it online. Honestly, I need some help with this. I don't know if I'm doing this right, and any help will be appreciated. This is my answer for i.
3
votes
1answer
81 views

Entity Relationship Design; The best scenario

TLDR; What would be the best design choice for the scenario below and how would each design react at extremely large data volume? I have experience working with large government database systems ...
5
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2answers
230 views

Dog Adoption Database Design

Apologies if this isn't the norm, but I am seeking advice for the database design for 'dog rescue/adoption'. I've done my normalization research and this is my first attempt at database design. Any ...
1
vote
1answer
53 views

ERD modeling organization and roles

I am trying to model the following scenario: -I have multiple company bureaus. -Each Bureau has multiple offices -Each office has multiple divisions -Each Bureau has employees that only ...
0
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2answers
47 views

What is the most efficient way to make a Locality Entity (Town, City, Village etc) with a Country Entity?

I am new to Database. I have a database with a UserProfile Entity. I need to add a Country and Locality(City, Town, Village) to the UserProfile. What is the most efficient way of doing so? This is ...
2
votes
1answer
63 views

Is this table in my ERD redundant? (Image)

I am developing a research article database for a project. My professor approved this design but I feel like the Author's_University table is redundant and that University_ID could just be added to ...
1
vote
1answer
87 views

How to add foreign key with more than 1 field in SQL Power Architect

In the picture, I got a model I'm building in SQL Power Architect. I already have table 1 referencing a field (CDCONTR) from table 2. But I want to make the foreign key to reference two fields from ...
2
votes
2answers
149 views

Best data modeling approch to handle redundant foreign keys in relational model

I am looking for advice on the best relational modeling approach to store surveys, questions, and responses. I am looking for which of the two approaches below looks best, or an alternative approach ...
0
votes
1answer
317 views

Superclass/Subclass Relationship Implementation in MySQL Workbench ERD Diagram

This is a relational model! Trying to figure out how to implement a 1:1 superclass/subclass relationship in the ERD diagram. I'm new to this so I'm not sure whether I have to type out all the ...
3
votes
1answer
442 views

ER vs database schema diagrams

when i search the web for er diagram and database schema these 3 diagram types found but all are named under er diagram.i want to know what is database schema diagram and what is er diagram why all ...
0
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1answer
289 views
1
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1answer
41 views

ESports League ERD

I'm creating a database for an esports league and am having some issues putting it all together for an ERD. Here's a quick rundown on how the game works: There are 2 teams of 5 Players each. These ...
1
vote
1answer
92 views

Help me to create correct ER Diagram [closed]

I want to create a database where one user can either be a Doctor or a Patient (but not both). So that, I can get all doctors or patients from doctor or patient table as well as I can search doctor or ...
1
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0answers
246 views

Quotation and invoice mysql table

I am trying to develop a small business web application for my friends business. I do have some php,html experience so I have done the interface and all. Now I am trying to work on the database. The ...
0
votes
0answers
27 views

Normalize to 3NF Question - Postal Codes/City [duplicate]

Normalize to 3NF and design an ERD for the following data: Name Street City Province Postal Code Home Phone Cell Phone Just want to see if I am doing this right. PERSON NameID Name Phone Number ...
2
votes
1answer
81 views

Should I maintain relationships diagrams in the back-end and the front-end?

I’m developing an Access 2010 database application. It is split into a back-end, holding all the tables, and a front-end, holding all the queries, forms, etc. I find the Relationships tool helps ...
5
votes
1answer
406 views

How to enforce a constraint over multiple tables?

I have the following five tables: PRODUCT FEATURE PROVIDER PROVIDER_PRODUCT PROVIDER_FEATURE The logic is as follows: A generic PRODUCT can have one or more FEATUREs. There are different ...
4
votes
1answer
117 views

Do I relate entities that are indirectly related when creating a student-course ERD?

I'm trying to create an ERD for a tutor center, this is what I understood from their operations: There is the tutor center director, then under her there are sections/departments. It, math/calculus, ...
1
vote
2answers
168 views

How to decide when is use ERD or UML for data modeling?

A UML diagram can be used both to model database designs and class designs, but an ER diagram should be used exclusively in database problems. How do you pick one graphical representation over the ...
10
votes
2answers
410 views

Conceptual ERD Multi-table many to many, or possibly recursive?

I'm creating a conceptual diagram [yes, I know I've included attributes and keys - but this is just for me to consolidate what I'm doing whilst learning] -- so please treat it as Conceptual with the ...
2
votes
2answers
173 views

How to review Database schema?

I am green been software engineer, my team lead give me a task in PostgreSQL database, I need to determine the relationship of the all 405 tables, but the problem is the database doesn't have any ...
1
vote
2answers
147 views

Trying to design database for eSports Teams - Issue with dependencies

I am trying to design a database in Access for an eSport league (specifically League of Legends North America). I will post what I have and then explain my issue. My issue comes when I try to ...
0
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0answers
60 views

table design approach for a rental application with several one to many relationships

I'm trying to go about designing a database/tables for the following situation I'm being presented. I'm developing a rental web application with MySQL as db engine. It is for a nonprofit organizations ...
2
votes
1answer
284 views

Bicycle Sharing Scheme - ER Diagram

Please compare the directions below to my ER Diagram and tell me if anything is wrong with my ER Diagram Please I think its accurate enough. Oxford City Council is preparing to launch an innovative ...
0
votes
1answer
63 views

Issue with forming correct relationship between subtype and another table in ERD

The focus is on the Cashier table and the Cash Accountability table. The rule is that only Cashiers have Cash Accountability and a Cashier ideally only cashes out once per day. Before I changed the ER ...
0
votes
1answer
105 views

Database Design / ER Diagram - Help Needed

Please take a look at this ER Diagram that I started. I just don't know if I've set it up correctly (I have not made any relationships yet). I just want to know if I have the appropriate "Tables" or ...