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Questions tagged [er-modeling]

7 questions
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How are ER modeled subtypes implemented in the database?

Sorry if this is too simple, but I've found a lot of documentation on ER-modeling recently, but all of it seems to skip over the actual implementation and I just want to clarify. Is a subtype just a second table with a foreign key to the supertype…
Boden
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Tool for modeling ER diagram and import in SQL server

Is there any tool for ER modeling and then converting models to a Microsoft SQL Server database? The tool should has this features: ER Diagrams shoud be in UML Notation (see this, the last is UML notation). Export models to a Microsoft SQL Server…
Isaac
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Issues with relating tables depending on a type

I'm working on a database model for a hypothetical fleet of vehicles for a company. There's 4 types of vehicles (cars, trucks, semi-trucks and buses) and 2 types of drivers. Both types can only drive one vehicle at a time, with Type 1 driving only…
iVikD
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Need help designing my database

I have a given number of entities, 6 of which are related to one another. However 4 of them (Namely, JobInfo, Child, Spouse and ParentInfo) are linked to the main Person/Employee entity and this employee entity requires the primary key of the…
Rye
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Is it possible to model tables belonging to different databases in the same schema?

I need to build a system that in order to deliver the desired results to the user, queries (it uses a join operation) two tables each of them belonging to a different database. Therefore between them there is no physical relationship. However,…
CiccioMiami
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ER Model for Quiz game

I'm trying to create ER Model for the Quiz game and I need help. What is the best solution for tracking user answers in the specific game? What do you think about putting it in GamesByUser table (GamesByUser would have a List ) ER…
Domagoj Hamzic
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how to determine weak and strong entity in ER model

ER modeling below situation " a car insurance company whose customers own one or more cars each. Each car has associated with it zero to any number of recorded accidents. Each insurance policy covers one or more cars, and has one or more premium…
장석인
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