entity-relationship

How do I Retrieve Relative Scores From a Subset of Entities in CoreData

Hi all, Sorry for the long question but I think it needs some background :S I have the following model in CoreData: A Guest can have any number of Scores in its scores relationship. A Score can have a maximum of two Guests in its guests relationship. For each pair of Guest entities I model have a Score entity with a value indicatin...

IPhone CoreData: How should I relate many child entities to thier parents

I am trying to import data from a database that uses primary key / foreign key relations to a core data database in Xcode. I have code that creates hundreds of child entities in a managed object context: Each child has an ID that corresponds to a parent. child1 parentID = 3 child2 parentID = 17 child3 parentID = 17 ... childn...

Doctrine does not export relation properly

Hi, I've got a MySQL 5.1.41 database which i'm trying to fill with doctrine, but doctrine does not insert the relations correctly. My YAML is: Locatie: connection: doctrine tableName: locatie columns: loc_id: type: integer(4) fixed: false unsigned: false primary: true autoincrement: true org_id: type: i...

How do I update with a newly-created detached entity using NHibernate?

Explanation: Let's say I have an object graph that's nested several levels deep and each entity has a bi-directional relationship with each other. A -> B -> C -> D -> E Or in other words, A has a collection of B and B has a reference back to A, and B has a collection of C and C has a reference back to B, etc... Now let's say I want ...

Accessing CoreData relationships

I have the following core data model with two entities: entity "item" which holds name, date, description and a to many relationship "image". image is optional. entity "image" holds url, name and relationship to one item. I load the executed Fetchrequest into this NSArray "entityArray" This is what I do to display my data in a UITabl...

Open Source - EER Modeling Tool

Is there a good open source or reasonably priced EER modeling tool for MySQL besides MySQL Workbench? I find the MySQL Workbench interface to be clunky. I would like to be able to manage my production schema beginning all design changes in the EER and propogating those out to my schema for created and altered tables. Is anyone use a to...

How do I serialize/deserialize a NHibernate entity that has references to other objects?

I have two NHibernate-managed entities that have a bi-directional one-to-many relationship: public class Storage { public virtual string Name { get; set; } public virtual IList<Box> Boxes { get; set; } } public class Box { public virtual string Box { get; set; } [DoNotSerialize] public virtual Storage ParentStorage { ge...

Cocoa Core Data - Efficient Related Entities Counts

I am working on my first iPhone application and I've hit a wall. I'm trying to develop a 'statistics' page for a three entity relationship. My entities are the following: Department - Name, Address, Building, etc. People - Name, Gender (BOOL), Phone, etc If I have fetched a specific department how do I filter those results and only ret...

General many-to-many relationship problem ( Postgresql )

Hi, i have two tables: CREATE TABLE "public"."auctions" ( "id" VARCHAR(255) NOT NULL, "auction_value_key" VARCHAR(255) NOT NULL, "ctime" TIMESTAMP WITHOUT TIME ZONE NOT NULL, "mtime" TIMESTAMP WITHOUT TIME ZONE NOT NULL, CONSTRAINT "pk_XXXX2" PRIMARY KEY("id"), ); and CREATE TABLE "public"."auction_values" ( "id" NUMERIC DEFAU...

Tool for convert SQL code to diagram

can any one say some way to convert SQL code to data diagram like ERD ? for som DBMS like MySQL or general SQL ...

Entity Framework 4 and persisting foreign key relationships

I am a pretty much a newbie to Entity Framework (specifically version 4) and I am trying to understand an issue I have. I have an ASP.NET MVC2 project I am using with Entity Framework 4 and a Repository class. I have a simple foreign key relationship that I have defined. When I run my MVC project I am able to load the MVC form and updat...

How to get address the object of an related entity with CoreData ?

Hi Ok, after I ran into a dead end modifieing an existing Apple example for CoreData, I started completely new creating my own project and that worked fine,..... until I tried to access a related entity. So here is what I did. I created 2 entities, where one is just the detail information of the other one, so there is a one-2-one rela...

jpa relationship

Hai friends I have created two table as person and address using jpa. I want to give one to many relationship between these tables. if i give the folowing @OneToMany(mappedBy="address",targetEntity=person.class,fetch=FetchType.EAGER) in the address table means its not working correctly. cn any one help me. Thanks in advance. ...

one to many jpa relationship

Hai I have created two table first table as student package com.crimson.rship; import javax.persistence.Basic; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.Id; import javax.persistence.OneToMany; @Entity(name="student") public class student { @Id private String stumailid; @B...

Model relationships in ASP.NET MVC

Hi I recently started evaluating ASP.NET MVC. While it is really easy and quick to create Controllers and Views for Models with only primitive properties (like shown in the starter videos from the official page) I didn't find any good way to work with references to complex types. Let's say, I have these Models: public class Customer { ...

I want define tables from ER Diagram.

I have a unary relationship. (Image Url : http://freezpic.com/pics/666c94955212a2f757fa25f9f7d31a5e.png) But I want define a table for person. The table has personID and personName column. What columns add it? ...

Are there any modeling tools that help visualize how a 3NF model would look like against EAV?

Would like to find low-cost relational modeling tools that will allow me to map a logical model in third normal form to a physical model based on EAV. Got any pointers? ...

High-quality ERD generator for PostgresQL under Linux?

Background MySQL Workbench can produce appealing and high-quality ERDs such as: Research What PostgreSQL ERD tools are available that meet the requirements? The following are unsuitable: dbVisualizer - Yellow squares. AquaFold - Yellow squares. SQL Developer - Coloured squares. Dia - Coloured squares. SQL Power Architect - Black a...

Define tables from a part of my ER Diagram.

I have a ER-Diagram (Show in http://www.4freeimagehost.com/show.php?i=f82997ca4d5d.png). In the diagram you see 2 entities and a 1:N relataion together. Project has 2 columns as ProjectID, ProjectName. Employee has 3 colums as EmployeeID, EmployeeName and ProjectID. A project has ONLY 1 project-manager and project-manager is a employee. ...

EntityManager does not update on flush()

Java EJB's EntityManager does not update data from a Consumer. A Consumer logs into a shop, buys some stuff and wants to look at his shopping-history. Everything is displayed but his last purchase. If he logs out and in, it shows. I have used JPA to persist buys/purchases (that are mapped to the Consumer)to DB. It seems like purchases...