I am trying my best to understand what is the difference between "ADO.NET - Entity Data Model" and "LINQ To SQL", but I cannot figure it out.
Can someone please explain the differences between the two and the advantages and disadvantages?
Thanks
Frank
Linq to SQL was actually a proof of concept for Linq. See The Origin of LINQ to SQL. Microsoft is putting its weight behind Entity Framework, although I believe it's not quite ready for prime time.
Anyway, this StackOverflow post provides some additional detail about the differences.
Linq to SQL is said to be dead (I don't think so though - it was way to well received by the development community). Entity Framework is its successor, if you want. It can access more data sources (more database types, and also different kinds of sources such as reporting services, business intelligence etc.). It's much more complex than Linq to SQL, and has a steeper learning curve, for example EF allows one class-multiple tables mapping. Other things are not possible with EF, such as specifying deferred loading - that's Linq to SQL only.
Related
I am planning to work on a new ASP.NET WebForms site in .NET 4.0. I used to use Linq to SQL and now I am thinking about EF4. My database is SQL Server only ever, simple business objects and most probably one to one relationships between Business objects and database tables.
It seems EF4 in its simplistic form works very much like Linq to SQL as an ORM. Drag the tables into the designer and with LINQ to do the database stuff.
Instead of learning and using two ORM's, it seems EF4 can do all of it. From the simple to the complex projects. From SQL Server only to hybrid database engines.
Will I miss anything if I go with EF4 only all the way for all kinds of projects and leave LINQ to SQL behind? I know EF4 is more complex (steeper learning curve) for simple projects but I don't find this a good reason to split my energy & time between two ORM's when one (EF4) can do it all.
I think the main negative point about EF4 apart from the steeper learning curve is its performance. Linq to Sql is faster and if that is important for your project than you might have to consider choosing Linq to Sql or straight ADO.NET instead.
However in most cases when performance is not a crucial issue for either simple or more complex projects I share your idea of not splitting the efforts and concentrating only on EF4.
What happened to Dlinq? I heard a few years ago that it was abandoned.
Was some of its code used to create Linq to SQL or the ADO.NET Entity Framework? Which one? In other words, which of the two latter technologies are a new avatar of the old DLinq?
I am learning ADO.NET Entity Framework and since I am just starting out, I believe the answers to these questions will help me get a better understanding of the subject. I usually start out learning about the history and the background of a technical topic. It feels like a warm up exercise that gives me a boost in confidence and increases motivation to learn more. Also, it puts things in perspective, which other developers may not have.
Over the last few months, I've read Linq to Objects and Linq to SQL somewhat, and have also compared the boilerplate that's generated by Linq to SQL vs. that generated by the Entity Framework's Entity Model tooling.
I can appreciate the intrinsics somewhat as in, how the two models' DataContext / ObjectContext relate, and how the former uses Table<T> where the latter uses an ObjectQuery, both of which are IQueryable and thus support the standard Linq query operators.
Linq to SQL looks a lot more like a rip off of DLinq.
DLINQ became LINQ to SQL. LINQ to SQL is not a rip off; it's an evolution.
What are the advantages of EF4 and under what circumstances is it preferred over LINQ to SQL?
LINQ to SQL will have no more future development. So EF is the way to go in the future.
Entity Framework vs LINQ to SQL (this should explain what you want to know)
Well, two of the major differences are:
1) EF can target multiple database engines, including Oracle and MySQL. Not just MS SQL Server.
2) You can do so-called "code first" schema development. Basically you create your object model, and along with some hints, EF will generate the schema for you.
Seems to me that Linq to Sql is great for rapid prototyping and simple CRUD scenarios. Anything more advanced or enterprisey would use EF4. (Or at least that's what MS would like us to believe :) I've had good luck with Linq to SQL in production, for what it's worth.
EF4 basically adds a whole bunch of OO-ness to the mapping that isn't present in LINQ-to-SQL, such as rich object inheritance models. My own take on it is that none of that is necessary for good design, and I have yet to come across a single scenario in my own work that warrants the added complexity EF4 brings to the table.
Having said that, Microsoft has deprecated LINQ-to-SQL and will not continue developing it, so it will eventually fall behind EF4 in capability and efficiency (if it hasn't already). So the pragmatic choice is simple: go EF4.
After trying both and spending over one weeks porting a project from linq to sql, I can say that I really prefer Linq to SQL. The main reason for this is that EF is more restrictive on what functions you can use in LINQ queries. In EF I had to cast my linq expressions to a list to be able to manipulate them any further. Sorry for not being able to remember any example, it's been a few months since I did this...
One of the really big plus sides for EF, is the ease of use in connection with WCF Data Services. Very handy if you are developing a web site that should have an RESTful API.
Also, even though Linq to SQL is quite mature, it is indeed a dying technology. It won't get any significant updates, that makes it harder to commit to Linq To SQL for a new project.
Thus far used sql server stored procedures for all my web applications... Now thought of moving to an ORM... I would like to ask SO users about LINQ to SQL
Is Linq to sql worth a try as a beginner to an ORM?
or should i look for some others... Any suggestion...
EDIT:
I have a sql server 2005 database with all tables....
How to use this db with Linq to sql?
Coming from using ADO.NET table adapters, LINQ was a revelation. A breath of fresh air. The veil was lifted. A new day dawned. And so on and such forth.
Start with Scott Gu's series here and check all his other blogs on the subject.
I envy you your impending joy.
Skip it. Second grade little ORM missing all the interesting features (and don't get me even started with EntityFramework - crap in v1, barely usable in v2).
I suggest getting ahold of NHibernate.
Even though I, unfortunately, don't do much Windows/.NET development anymore, I still think that C#/.NET is the best programming environment around and that Linq is a great ORM. If you're on the .NET/C# platform, use it. There's good documentation, a large community of users to help you, and very solid implementations.
While Microsoft SQL Server doesn't get a lot of buzz, it is a very worthy database to be the platform underlying linq.
If you're just starting, then I recommend you ignore LINQ to SQL. Microsoft will be placing all of their development efforts behind Entity Framework, which is more powerful and general than LINQ to SQL.
Coming from a similar situation I found linq-to-sql worked really well. We previously used a repository pattern and managed to follow it pretty closely with linq to sql in about half the time. Linq-to-Sql will also allow you to write and use regular store procedures.
For a beginner I found the linq-to-sql sections of the Nerd Dinner tutorial a good starting point.
Personally, I think that L2S is a great choice for a ORM beginner because it's really easy to use, but still gives you plenty of power. IMO, if you are doing new SQL Server work, L2S is the best and easiest ORM available. It's not perfect, but neither is anything else out there.
Also, PLINQO adds a lot of the missing features to L2S that bring it more in line with EF, while maintaining the simplicity and speed of L2S.
I have to build a website for a news channel..
Please help me decide which technology to use for data operations?
1) Linq to Entities
2) Linq to SQL
3) Fluent NHibernate
4) ADO.Net
Website will be based on ASP.Net MVC and C#.
Main Issues:
1) Should be easy to maintain and scale.
2) Good Performance
Please express your view with an example if possible..
Thanks
Chitresh
Pro and cons:
LINQ To Entities
Allows you to add another layer of abstraction (entity) instead of mapping directly to tables (like in LINQ to SQL). Support multiple data providers (not just SQL Server). Require a bit more learning time than LINQ to SQL. Provide unit of work concept. Medium to High learning curve.
LINQ to SQL
Allows you to easily map your tables, stored procs, etc. Provide unit of work concept. Only work on SQL Server backend. Easy to implement, but require dbml rebuild if db schema changes (1 way synchronization from db to object), so a bit harder to maintain. Low - Medium learning curve. Performance, ... I think Stack Overflow is using LINQ to SQL. How do you think it performs? Have unit of work concept.
Fluent NHibernate
Can't comment ... know nothing about it. If it is anything like NHibernate, should be quite flexible. Probably high learning curve. Someone correct me on this...
ADO.NET (Not talking about Named DataSet here...)
Should be the fastest (no abstraction). Flexible, bend it anyway you want. Low learning curve. Very basic, do everything yourself approach. Most of the time I go this route for simple project. Can lower productivity. You can augment it with code generation to gain some productivity.
Your other options... Subsonic perhaps.
NHibernate(Fluent NHibernate)
Fluent NHibernate is a component to help you map your Entities so that NHibernate knows where it's gonna put your data from the database. If you never used NHibernate it can be a little difficult to know how to map and handle a NHibernateSession but there are lots of information here on stackoverflow and other places like S#arp for an exemple of session handling and Summer of NHibernate to get some lessons in mapping.
I would go with Linq to Entities or NHibernate (actually, I would go with NHibernate, but that is one I'm the most familiar with) -- AND ADO.Net (but just a little bit).
Start by doing everything you can with NHibernate/Entities. Once it is up and going you will find it remarkably productive. But there are situations where you will need a bit more performance (do you have a good profiling tool?). For those cases, code them in straight Ado.Net (that should make up less than 10% of your database calls). With NHibernate, you can use the NHibernate session to get your connection object for you as well.