Object-relational mapping (ORM) is a technique for mapping between object-oriented systems and relational databases.

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ORMLite on App-Server [on hold]

I am wondering if it is a good idea to use ORMLite as persistence layer in Java EE environments? I am also uncertain about the implementation of ORMLite in a JAX-RS Jersey environment in particular. ...
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1answer
73 views

Does ORM at any point become a “requirement” for RESTful API?

I've started building a RESTful API in PHP's Slim framework. The framework appealed to me because of its light-weight design and routing features. I am using PostgreSQL for the database. However, ...
1
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1answer
203 views

Is DDD any good nowadays? [closed]

This is not a rant about DDD but rather some experiences and observations I've made through the past 2 years since I first learned about it. With this post, I'd like to hear what other programmers ...
0
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1answer
106 views

Implementing a NoSQL and RDBMS compatible DAO

What would be the correct way to design a DAO which implementation is first going to be targeting a MS SQL database with a STAR model, but yet, business requirements specify the application must be ...
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6 views

Which ORM should I use for Node.js Express and Postgress [migrated]

I have been looking around an architecture for my backend services that needs to be developed using open source technology. A Node JS with Express is an option for REST-API. However, what about ...
0
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1answer
101 views

ActiveRecord equivalent in Java [closed]

My question is fairly simple.. What is the closest ORM to ActiveRecord that I'd be able to find for Java? In other words, in terms of thinking patterns and knowledge, with limted development time, ...
0
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1answer
36 views

Class Table Inheritance: do child tables need a primary key?

I'm using the Class Table Inheritance architecture with my application and have read Fowler. When mapping my database tables to classes in code, I've realized I have no need for an "ID" property on ...
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1answer
67 views

Limiting complexity in JPA programs Java/Hibernate

I've been working on a new application for some months now. It's my first big JPA program, and is still in the early stages. However, the complexity of my JPA object tree is becoming a growing ...
2
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1answer
92 views

What TDD/BDD tests should be writen to test an ORM

So I'm writing an ORM for NodeJS and using Mocha + Chai to test it. What I want to know is, what tests I should write to it, insertion tests should also have a querying test so I can check if the ...
2
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1answer
38 views

Solutions To Partial ORM Retrieval

I have read the following question regarding whether it is best to use objects with fully or partially populated data members. The 3 suggestions were: that perhaps using a fully populated ORM model ...
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0answers
63 views

Best approach to save relationship mapping of country,state,city in orm

I am building a project in play framework java with jpa and I want set country,state,city dropdown fields in a form to be dynamic(from database).So only admin can increase or decrease the value of ...
7
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3answers
190 views

How to model and store an entity which has “one or more” values

I'll use C# to design the model to be persisted Let's suppose I have the following entity: public class Episode { public int Id { get; set; } public string Title { get; set; } public ...
8
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2answers
263 views

Best practices for serialization of DDD aggregates

According to DDD domain logic should not be polluted with technical concerns like serialization, object-relational mapping, etc. So how do you serialize or map the aggregates' state without publicly ...
0
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0answers
57 views

Entity Framework and separating DAL from domain entities

If I have a normalized db, it's unlikely to map 1 to 1 with my domain entities. So I customize my EF entities to fit the domain. But now my EF entities are essentially my domain entities and my DAL is ...
2
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1answer
62 views

Creating/updating entity save strategy

Please note: although I'm talking about Java in this question, what I'm asking about here should really be language-agnostic. I am dabbling in OR/M for the first time, and have cooked up the ...
1
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1answer
285 views

Programmatically extending Hibernate table/entity definitions in Spring, how?

I would like to know if there is a way —maybe with AOP— to extend table/entity definitions so that I can add functionality across the board that requires persistence. Let me explain what I want to do ...
2
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5answers
175 views

Stored Procedures, ORMs and other application layers

I'm just starting out on a project to develop a new, fairly substantial web application which has an underlying MSSQL database. We're hiring a team of developers to write the application (in .NET) and ...
0
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0answers
64 views

Syncing structured data and files in Android App with an ORM?

I am developing an Android App which I have developed for iOS before. The app requires that structured data and files are synced across android devices. In iOS, I was using Core Data and synced to ...
0
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0answers
11 views

compare different approachs for saving related records whose values may change

On a web application for accounting services, I have the good old Invoice. To keep this example as simple as possible, each Invoice has many rows, and each row has its item with its price. At the ...
0
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1answer
50 views

Control (avoid) changing fields with side-effects

I have been thinking about a design problem and possible solutions in my own. I am pretty sure I am not the first one to have noticed it, but I cannot google for it since I do not know the standard ...
0
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1answer
80 views

Inverse property naming (ORM scenario) [closed]

I have a class that represents a process. In this process there are inputs boxes and output boxes. public class Process { public long ProcessId { get; set; } public virtual List<Box> ...
2
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2answers
58 views

How to ORM non-disjoint specializations

Consider this highly simplified sample of relational data (each table may be involved in one-to-many and many-to-many relationships not shown here): people +-------+------+--------+ | name | born | ...
2
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2answers
73 views

Domain/Model objects attributes good practices

Simple question: Should model/domain objects only include attributes that are meant to be persisted in a database or serialized to any other specific format? My understanding of a domain/model object ...
0
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0answers
27 views

Managing allocation calendars for an employee set [duplicate]

IN view of creating a MIS (Management Information System) one architectural/design issue that's confronting us is managing allocation for set of employees. Scenario: Employees get allocated to ...
6
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4answers
399 views

Heterogeneous Associations - Data Modeling When an Object that Must Relate to One of Many Classes

Suppose you have 3 classes: ClassA, ClassB and ClassC. Now suppose you have a class Message. You want a one-to-many relationship between each one of those three classes and the Message. The goal is ...
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1answer
66 views

How to associate both a collection and one item of this collection to an entity

I'm working on a project in which I have an entity, we may call Users and another entity Address. I want to define the entity User in a way that an user would have a collection of addresses ...
0
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1answer
32 views

Migrating single-layer ORM based app to multi-layer API

I'm trying to understand what is the best way of migrating a website that works in a single layer and gets all the data via an ORM, to one that uses multiple layers, using an API backend to get the ...
0
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1answer
132 views

Real time middleware system: Direct DB access vs REST API access

I'm developing a complex environment which involves a web application, a mobile app and a real time middleware system which accesses the DB for on-site tag readings. Currently, the web application ...
2
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1answer
97 views

Finding a way to simplify complex queries on legacy application

I am working with an existing application built on Rails 3.1/MySql with much of the work taking place in a JavaScript interface, although the actual platforms are not tremendously relevant here, ...
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2answers
128 views

Data Access Objects old fashioned? [closed]

A couple of weeks ago I delivered some work for a university project. After a code review with some teachers I got some snarky remarks about the fact that I was (still) using Data Access Objects. The ...
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2answers
224 views

Limitations of the Identity Map pattern

After asking about the implementation in Ruby of the Identity Map pattern because the potential memory leak in long running server apps, I am considering my initial concept of that pattern. Initially ...
0
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2answers
616 views

Proper Query Object Pattern - NHibernate

I was looking to an alternative to Repository Pattern and I've read about "Query object pattern" (http://lostechies.com/jimmybogard/2012/10/08/favor-query-objects-over-repositories/). However the ...
0
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0answers
50 views

Extending database model of ORM in subproject

I have a maven project which contains some entities which are stored in a database. The purpose of this project is to manage personal information, users, locations, etc. This project can work on its ...
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2answers
107 views

How far can I drift from my original domain model and still have the benefits of an ORM?

I have the following domain models: public class User { public int Id { get; set; } public ICollection<Product> Products { get; set; } } public class Product { public int Id { ...
0
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1answer
172 views

Doctrine 2 and Concrete table inheritance

I use Doctrine 2 and I've read some articles on inheritance strategies' mapping with ORM. I've seen three main strategies : "Class table inheritance", "Concrete table inheritance" and "Single table ...
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1answer
184 views

PHP - Repository matrix pattern?

I'm trying really hard to refactor some of my legacy code in the project using best practices and design patterns + DDD so I'd love some feedback on an issue I'm currently having. Let's assume that I ...
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1answer
337 views

How to use ORM in MVC?

If I want to use ORM in MVC system Which is/are correct? Use ORM object to replace Model Encapsulate ORM inside the Model Use ORM outside the Model, use ORM to access DB, and then use one instance ...
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0answers
57 views

Example of persisting an inheritance relationship using ORM

I have some experience with OOP and RDBs, but very little exposure to web programming. I am trying to understand what non-trivial types of problems are solved by ORM. Of course, I am familiar with the ...
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1answer
228 views

How do you handle domain logic that spans multiple model objects in an ORM?

So I know that business logic should be placed in the model. But using an ORM it is not as clear where I should place code that handles multiple objects. E.g. let's say we have a Customer model which ...
0
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1answer
267 views

Many-to-many in OOP: Class A instantiates Class B, which instantiates Class A, which

I am mapping Field1 to Field2. The map object instantiates the field object and vice versa, creating an infinite loop. This is in PHP. class field { protected $maps; // mapCollection object. all ...
2
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1answer
196 views

Persistence frameworks and common sense

I have studied some persistence frameworks mainly Hibernate, DORM, TMS Aurelius and I'm wondering. In a model of type: TOrderFiscal < > ----- > Items < > -------- > TOrderItem ...
0
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1answer
76 views

DB Design: How to link a single column to a collection of entities

I have a db design question that I am sure has been quite extensively covered but I cannot find a good answer already. The problem is how to efficiently link a single school course to a collection ...
4
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5answers
216 views

Is it bad software design to mix JDBC SQL calls and use an ORM in an application? [closed]

Is it bad software design to have JDBC/raw SQL and also use an ORM? I don't mind using an ORM for boilerplate CRUD, but some queries are better in SQL (for me). I'm not arguing for or against ORMs. ...
5
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4answers
6k views

How to get around the Circular Reference issue with JSON and Entity

I have been experimenting with creating a website that leverages MVC with JSON for my presentation layer and Entity framework for data model/database. My Issue comes into play with serializing my ...
3
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3answers
430 views

How does accumulating large amounts of business logic on the model objects make building strong service contracts harder?

I heard a couple of times that putting business logic in database models is bad down the road. I just read this in blog of a Rackspace employee: The Django ORM also tended to have us accumulate large ...
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1answer
112 views

Finding next free IP in a network

I have an IP network and want to automatically find a free IP address to provision a new server. Due to frequent server additions/removals the used IPs might be quite fragmented over the whole address ...
2
votes
1answer
372 views

What kind of object relational mapping is appropriate here?

In my database I have a table that looks like this Master(ID, Name, Attr1...). Every ID will have at least 1 entry in additional tables that have additional attributes. Those tables specialize the ...
0
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1answer
987 views

Android: Considering an ORM tool [duplicate]

I am developing an Android app in which I have to add chat functionality. Also, I have to save the chat history. I will accomplish this task using SQlite. But, I am not sure whether should I consider ...
0
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1answer
567 views

Audit trails and entity relationships

I'm working on an order system and implementing an audit log. Two main concerns are: 1) While auditing a line item , you should only see audits for the line item 2) While auditing an order, you ...
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2answers
177 views

Setter Validation can affect performance?

In a scenario where you use an ORM to map your entities to the DB and you have setter validations (nullable, date lower than today validation, etc), every time the ORM gets a result, it will pass into ...