I'm reading up on .NET things again after a brief (and occasionally ongoing) stint with Ruby on Rails. I'm wondering if LINQ is still a choice when choosing an ORM for new applications, or if I should learn something like NHibernate instead which seems to still be going strong. I know that Linq has basically been subsumed by the Entity...
I have been using ADO.NET in favor of LINQ to SQL (or Entities) up to this point. I'm starting a new project that should be smallish, at least at first but I would like to have room to expand down the line. I feel now is a good time to get into LINQ. I've avoided it for quite a while; however, I'm concerned by the current direction of...
I find that the use of ActiveRecord affects the way I design the database schema (though I wish it wouldn't). I'm thinking about the inefficiency of fetching data and how to reduce the overall number of queries. The find :include option can only get you so far. I come from writing stored procs that grab everything you need (for a part...
I have a model like this: class Task(models.model): TASK_STATUS_CHOICES = ( (u"P", u'Pending'), (u"A", u'Assigned'), (u"C", u'Complete'), (u"F", u'Failed') ) status = models.CharField(max_length=2, choices=TASK_STATUS_CHOICES) prerequisites = models.ManyToManyField('self', symmetrical=Fals...
I have learn about Object role modeling but not about Object-relational mapping and I want to know if they are two ways of doing the same thing and what are the pros and cons? To me Object role modeling makes a lot more sense. Could you make a brief but easy to understand comparison if they can be compared. Cheers ...
I have begun developing an application using the Entity Framework. I have added a namespace to contain all of my user management code MyApp.Users for example, and this contains a model that has been marked internal to the namespace and only exposes functionality to the rest of the system via interfaces. This is all good. I now wish to ...
I am trying to define a SQLAlchemy/Elixer model that can describe the following relationship. I have an SSP table, which has multiple Foreign Keys to the POC table. I've defined the ManyToOne relationships correctly within the SSP object (allowing me to SSP.get(1).action.first_name correctly). What I would also like to add is the other s...
In the current application I'm developing I'm using fluent nhibernate to configure nhibernate for use as an ORM. I want to be able to add a prefix to all the table names used in the application, so that if I use a database that is already servicing another application, there are no naming conflicts between the two applications. So for...
There are a few "should I chose this or that" questions on SO and Google, as well as a lot comparing LINQ2SQL and LINQ2E. I've seen drawbacks, differences, cons, pros, limitations, etc. I cannot say I'm an expert but I'd like to know "what would you do" if you faced this scenario and why. I have to add stuff to an "old" 2.0 app that ha...
I'm in the early stages of a project, and it's not clear yet whether we'll need a "real" database (i.e. SQL Server et al). So I've been doing some prototyping using MS-Access, which is working fine so far. (developing in C#/VS2008/.Net 3.5/MS-Access 2000). However, the object-relational impedance mismatch is already becoming annoying, ...
I am just starting to model the data for a new project, which must be persistable. Looks like the most natural OO model will have lots of nested .Net generics. Lists of objects, and these objects will also contain Lists of other generic types, and so on, nested at least three levels deep. Ideally, I'd like to just design the data mo...
I'm about to undertake the task of abstracting out all SQLExceptions from an ORM's public interfaces with something more generic - that is declaring a generic exception which would in most cases wrap say an SQLException), and I'm wondering about naming. I'm thinking of something along the lines of BackingStoreException or StorageMediumE...
I'd like to use Subsonic in a shopping cart application, but I'm trying to replace code that is using Session to store an Order object. That Order object has a collection or OrderDetail objects that are added to the collection through the shopping cart process. I'm impressed with what Subsonic can do and I think I'm missing how I could...
I have a model where tasks are pieces of work that each may depend on some number of other tasks to complete before it can start. Tasks are grouped into jobs, and I want to disallow dependencies between jobs. This is the relevant subset of my model: class Job(models.Model): name = models.CharField(max_length=60, unique=True) class ...
Lots of "BAW"s (big ass-websites) are using data storage and retrieval techniques that rely on huge tables with indexes, and using queries that won't/can't use JOINs in their queries (BigTable, HQL, etc) to deal with scalability and sharding databases. How does that work when you have lots and lots of data that is very related? I can on...
I am just starting to model the data for a new C# project, which must be persistable. Looks like the most natural OO model will have lots of nested .Net generics. Lists of objects, and these objects will also contain Lists of other generic types, and so on, nested at least three levels deep. Ideally, I'd like to just design the data m...
Hello good fellas!i'm a bit confused about something right now about hibernate property.I have a parent class that doesn't need to browse it's child for now , eg the type of table that just hold information (id| currency | description) so in the mapping file of the parent i ignore the set tag. in the child class i have reference to the p...
I have been using Linq-to-SQL. What is a good option for working with mySQL? I have been looking at NHibernate, Entity Framework, etc. Some comparisons (pros, cons) would be helpful ...
I have a RecipeJDO that contains a List<IngredientJDO>. RecipeJDO "owns" the ingredients. This has been working well for me for several weeks. Now I'd like to introduce a new class "GroceryListJDO", that references the ingredients owned by various recipes. When I try to persist a new GroceryListJDO I get the following: javax.jdo.J...
Are ORM frameworks such as Entity Framework, Linq to SQL, Subsonic, NHibernate promote good programming practice or just a tools to speed up the development? Should we used this technologies inside the presentation layer? ...