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Questions tagged [datamodel]

According to Hoberman (2009), "A data model is a wayfinding tool for both business and IT professionals, which uses a set of symbols and text to precisely explain a subset of real information to improve communication within the organization and thereby lead to a more flexible and stable application environment.

In software engineering, the term data model is used in two related senses. In the sense covered by this article, it is a description of the objects represented by a computer system together with their properties and relationships; these are typically "real world" objects such as products, suppliers, customers, and orders. In the second sense, covered by the article database model, it means a collection of concepts and rules used in defining data models: for example the relational model uses relations and tuples, while the network model uses records, sets, and fields.

References:

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what is difference between a Model and an Entity

I am confused to understand what is the meaning of this words: Entity, Model, DataModel, ViewModel Can any body help me to understanding them please? Thank you all.
agent47
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Evaluating HDF5: What limitations/features does HDF5 provide for modelling data?

We are in evaluating technologies that we'll use to store data that we gather during the analysis of C/C++ code. In the case of C++, the amount of data can be relatively large, ~20Mb per TU. After reading the following SO answer it made me consider…
Richard Corden
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Column-family concept and data model

I'm investigating the different types of NoSQL database types and I'm trying to wrap my head around the data model of column-family stores, such as Bigtable, HBase and Cassandra. First model Some people describe a column family as a collection of…
Niels van der Rest
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How / if to refactor a Delphi program using only forms and data modules

After years of coding Delphi programs as untestable code in forms and datamodules, including global variables, and the only classes are the forms themselves, containing all the code I need for the form UI itself. How would I convert the code to a…
Osama Al-Maadeed
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Object Oriented Database Vs object Relational Database

I wonder how Object Oriented data modeling is different from Object Relational data modeling? Is it something like the pluses of both object oriented and relational data modeling were clubbed to achieve object relational data modeling? cheers
Arnkrishn
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Data Model for Boolean Expressions

Do you know a way to organize boolean expressions in a database while allowing infinite nesting of the expressions? Example: a = 1 AND (b = 1 OR b = 2) The expression as a whole shouldn't be stored as varchar to preserve data integrity.
Sebastian
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How to properly delete and re-add Entity Data Model

newbie to Entity Framework here. Using VS 2010 and SQL Server 2008 express DB. I was having trouble refreshing an Entity Data Model after adding new tables. So, I followed a suggestion I found here to just delete and regenerate the model. I get to…
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Angular 2 define data models for multiple modules

I'm currently starting a new project with Angular 2.0 (release Version) and I want to define some global data models/schemas. As I understand it, Angular 2 has no default way of handling pure data classes like this: export class TestModel { id:…
A. Ziegler
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How to load just the last record from entity with LINQ?

I want to fetch value of field named "Gram" from the last record and put its value into a variable, without using any conditions. First I tried int value = int.Parse(Entity.TblGold.LastOrDefault().Gram.ToString()); Second I tried int value =…
amin
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Working with Protocol Buffers and internal data models

I have an existing internal data model for a Picture, as follows: package test.model; public class Picture { private int height, width; private Format format; public enum Format { JPEG, BMP, GIF } // Constructor, getters and…
Catchwa
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asp.net mvc models vs entity framework models

Would it be best practice to create a model in your asp.net mvc - model folder. Use these models with your views and by using a service layer to "adapt" my model to the EF-model. Or have you used another approach. The problem with this approachs is…
David
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Designing a data model for versioned data

I'm looking for some input on the best way to design a data model that revolves around versioned data. There will one-to-many and many-to-many relationships which can all change from version to version. I'm looking for some different strategies…
binarymelon
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MOMC error with XCode4 and Data Model Compile

Whenever I build my project, I'm getting the error: Command /Developer/usr/bin/momc failed with exit code 1 I've read posts here about deleting extraneous Data Model versions as a fix, and nothing works. I'm stumped because nothing changes the…
beeudoublez
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what exactly is a map dimension in a multi-dimensional map?

Like many these days, I am an old relational-model user approaching Cassandra for the first time. I have been trying to understand Cassandra's data model, and when I read about it I frequently encounter statements that encourage me to think about…
pohl
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Xcode Data Model Editor not appearing

I'm using Xcode 4.2 and I'm trying to use Core Data. Upon clicking the .xcdatamodeld file I see a strange view instead of the Data Model Editor View. I have reinstalled Xcode 4.2 and have even created a starter project from scratch with Core Data…
Sanjiv Jivan
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