I have following database structure, CREATE TABLE IF NOT EXISTS `analyze` ( `disease_id` int(11) NOT NULL, `symptom_id` int(11) NOT NULL ) ; CREATE TABLE IF NOT EXISTS `disease` ( `id` int(11) NOT NULL auto_increment, `name` varchar(10) NOT NULL, PRIMARY KEY (`id`) ) ; CREATE TABLE IF NOT EXISTS `symptom` ( `id` int(11)...
I have a legacy database with a table storing a many-to-many relationship, but without a single primary key column. Is there any way to convince Django to use it anyway? Schematically: Product 1<---->* Labeling *<---->1 Label The Labeling table uses (product_id,label_id) as a compound primary key, and I don't see any way to inform Dj...
I have a mapping structured in this way: public class Person { public IDictionary<bool, Action> Actions { get; set; } } public class Action { public string Name { get; set; } } // Map for Person public class PersonMap : ClassMap<Person> { public PersonMap() { Id(x => x.Id) ... Map(x => x.Name) ... Table(...
Hello I am currently working on a DVD Store App. There are two tables in which I am having an issue. First is the Genres and the other is DVDCatalog. I need that DVD can be listed in one or more Genres. So, to do that I have to store like the IDs of the Genres (4,5,6). This way I can't make a relationship with the GenresID in the Genres...
I have modeled a Person/Tag relationship. It's a many to many relationship; a person can have multiple tags and a tag can be associated to multiple people. I am trying to run a query to see get a list of people, that have been tagged with EVERY tag of a set of tags. For Example: Every person that has been tagged with 'FOO' and 'BAR'. ...
Ok so this is probably a trivial question but I'm having trouble visualizing and understanding the differences and when to use each. I'm also a little unclear as to how concepts like unidirectional and bidirectional mappings affect the one-to-many/many-to-many relationships. I'm using Hibernate right now so any explanation that's ORM rel...
I have a table that holds bibliography entries, with a bibID primary key. I also have a table that holds a list of categories that can be assigned to the bibliography entries with a categoryID primary key. A table links these two tables as bibID:categoryID, so that each bibID can be associated with multiple categoryIDs. Categories assoc...
This seems very basic but I can't figure it out. I've got a table "item_tags", and I want to select all of the items that match tags 1 and 2 (as in, each item has to have both tags). How would I do this in mysql? Create table is: CREATE TABLE `item_tags` ( `uid_local` int(11) NOT NULL DEFAULT '0', `uid_foreign` int(11) NOT NULL D...
I'm still a neophyte when it comes to SQL queries, so I was hoping someone could lend me a hand. Assume I have 3 tables, Skill, Set, and Contact, and 2 linking tables, SkillSet and ContactSet. (the 3 tables have an "ID" column that is being used as a primary key) Contacts can have any number of sets, and vice versa (many-to-many) Sets...
I'm writing an ASP.NET MVC 2 application that uses Entity Framework 4 and WCF Data Services. I want to manipulate the many-to-many (composite key) relationship between Duties and Workers based on the state of some checkboxes. A Worker may have zero or more duties. A Duty may have zero or more workers. This code is from one of my contr...
Hi. I have three tables: player [id, name] attribute [id, name] player_attribute [id, player_id, attribute_id, value] each player can have different attributes, some of them don't have any. Now I need to search for players with certain attributes, e.g. all players that have number 11, and their first name is John. At this moment I al...
I was looking at snippets and tutorials for quite some time now, but I can't find a complete answer - just some bits and pieces. I have a database with 3 tables: Product: id uniqueidentifier name nvarchar(50) Category: id uniqueidentifier name nvarchar(50) ProductCategory: fk_product uniqueidentifier fk_category uniqueiden...
How do I tell Hibernate to create a primary key for a many-to-many relationship in an .hbm file? ...
Dear All, I have problem with display record from django . multi devices have multi services and others many-to-many model models.py class Service(models.Model): service_name = models.CharField(max_length=25) service_port = models.IntegerField(max_length=6) class Devices(models.Model): hostname = models.CharField(max...
I have the following classes: public class A { public virtual int Id { get; private set; } public virtual IDictionary<MyEnum, B> MyBValues { get; set; } } public class B { public virtual int Id { get; private set; } } public enum MyEnum { Value1, Value2, Value3 } And would like the following tables: A ------------...
Lets say I have a model similar to the one below, and I need to Fetch all 'Person' of a specific Company.companyName sorted by personRole.roleWeight This is the model I have at the moment: Entity: Company Attributes: companyName Relationships: companyRole Entity: Role Attributes: roleName, roleWeight Relationships: rolePerson, Rol...
Hi, I have django ModelForm for model with ManyToManyField. I want to change widget for this field toCheckboxSelectMultiple. Can I do this without overriding a field in a form definition? I constantly use code similar to this: class MyModel(ModelForm): m2m_field = forms.ModelMultipleChoiceField(queryset = SomeModel.objects.all(), ...
Please help an EF n00b design his database. I have several companies that produce several products, so there's a many-to-many relationship between companies and products. I have an intermediate table, Company_Product, that relates them. Each company/product combination has a unique SKU. For example Acme widgets have SKU 123, but Omega w...
I have a many-to-many model, following the example in this great railscast My model links authors to each other. I'd like to validate that an author cannot friend himself. I know I can handle this at the UI level, but I'd love to have a validation in place to prevent a bug in the UI from allowing it. I've tried validates_exclusion_of, b...
Hi, I'm trying to make a Match model which includes the players lined up during that match. So each Match hasMany Players and each Player hasmany Matches. match = { '_id' : ObjectID('978tqwbi9873gofiu'), 'home' : 'Argentina', 'away' : 'Brazil', 'lineup-home' : [ {'name' : 'Lionel Messi', 'goals' : '2', 'timeon' : 30 }...