I'm generating domain model using LINQ to SQL via the VS2008 built-in editor. That works really well, too; when I adjust my database schema I simply delete everything from the editor and then pull it back in from the server explorer by selecting all tables and dragging them into the designer surface. That works great too.
Now the problem: I have properties that I manually set to autogenerated, readonly etc. using the property inspector on the right. Everything I re-create the entire schema I have to do this manually all over again.
Is there a way to persist these settings externally and/or automate them to bring it back to the state from before?
You can use something like the Huagati DBML Tools. This will allow you to update the DBML file from the VS designer.
I've also used the following process before:
Create my schema in SSMS
Create a script that uses the SQL Metal command line tool to generate the DBML file
As the DBML file is XML, you can run transformations on the file. I used this to simply change a few things like setting certain fields to be auto-generated (DateCreated, etc).
Then, either use SQL Metal or T4 to create the model files from the altered DBML file.
This process worked great - however I had complete control over the database schema. This process also allowed me to use L2S with SQL Server Compact Edition.
Hope this helps!
T4 Toolbox has a Linq to Sql Schema generator which allows you to develop your Linq to Sql applications in a model first approach. I have used it a little and it works really well, here is a blog post with details and usage info.
Your solution may appear to work when you have very few database entities / tables, but it does not scale and as you've found, syncing is less than ideal.
Do not use the Visual Studio 2008 LinqToSql O/R Designer
After looking at many alternatives to the problems you are describing with LinqToSql, I decided to abandon LinqToSql altogether as I didn't find any of the workarounds very good. Competing ORMs don't have the silly problems that LinqToSql has and they are much more mature and feature rich.
I could/should probably list some of the alternatives I ran across, but I don't want to spend the time and give you false hope, sorry.
Related
We are looking to introduce odac into our application but I am running into a number of issues and I can't seem to find any solutions that fix our issues.
We are using an oracle database and trying to use ODAC 12c Release 1 (12.1.0.1.0) with Oracle Developer Tools for Visual Studio.
In our model we would like to have multiple schemas so we can perform cross schema queries. The schemas which we select in the filter for the database connection appear when we are creating the model. However when we try to update our model from the database only the default schema is visible. Sometimes this can be fixed by opening the relevant part of the database in Server Explorer in Visual Studio but this doesn't always work. This fix never works after we add multiple connection strings for the same model (depending on the location of the user will depend on which database the user gets directed to).
The next issue we are having is that we can't the return types of stored procedures to be auto-generate. I have tried to retrieve the column information but it is never able to retrieve the metadata. I have seen a few suggestions of modifying the stored procedures then getting the column information and reverting the stored procedures but this is something we would like to avoid. Also the suggestions don't seem to work on oracle databases (but that could be me, I don't have much experience with databases).
The final issue (this is a minor issue) is that I cannot figure out how to get the generate code to omit underscores from the classes/methods generated. This isn't a huge issue it is purely to make it easier migrating the code we have.
I usually create a solution folder in Visual Studio and put my DB scripts in them. I always use at least this set of scripts:
Drop model
Create model script
User functions
Stored procedures
Static data (lookup tables)
Test data (not deployed)
Then I simply combine them and run against an SQL Server so I'm able to recreate the whole DB in a single step (by combining these scripts into a single one and executing it).
Anyway. I've never used projects in either:
Visual Studio or
SQL Management Studio
I've tried creating SQL Server 2008 Database Project in Visual Studio 2010, but I'm somehow overwhelmed by all the possible server settings (which I prefer to stay default as set on the server anyway). So I'm a bit confused: Should I use this project template or should I just do the same thing I always did?
What do you use and why? What are advantages I may benefit from by using either?
If I were you I would continue to do it the way you are doing it. In fact I do! The advantages of having the actual .sql files right there in a folder for you to use/edit/look at in my opinion are far better than the advantages you get by using a DB project. DB Project would be used if you were doing something like Storage Reports, were you have to communicate with like 8 databases and compare then to 8 different databases and save result sets etc... Now don't get my wrong there are advantages of Database Projects, I just don't think they are actually doing much help when you have such a simple setup that works already.
Advantages of the SQL Server 2008 Database Project in VS10:
Not having to switch back and forth
from your current client you use to
communicate with your SQL server.
Decent Data and Schema compare tools.
Gives you a one-click way to reverse
engineer a database into source
control, and keep it up to date.
You can compare projects to physical
databases and vice-versa. (This makes it pretty easy to keep your database up to date, no matter where you make change it: file system database project, or in the physical database itself)
If the current tool your using is not specifically tailored to SQL Server, this one is.
Extremely helpful if you need to do
unit tests directly on the database
without using abstractions.
If you're looking for something a little less complicated, you might want to try SQL Source Control. This won't even require you to maintain scripts, as it doesn't this for you behind the scenes. It will, however, only work as a solution for you if you use either TFS or SVN. And it costs $295...
It has a 28-day trial period, so if you're happy to try it out, I'd be interested in your feedback.
I'm currently investigating ASP.NET MVC 2 and LINQ to SQL. It all looks pretty cool. But I have a few application and development lifecycle issues.
Currently, I design the DB in SqlServer Management Studio.
Then I update my DBML files by deleting and re-importing modified tables.
Issues:
I can't find how to simply update the whole DBML schema.
My DBML then loses some of the changes I made such as renaming relation members or mapping of some int to an enum.
If I want a SQL script to deploy my DB (or to keep the schema under source control), I need to go use the 'Genererate Script' SSMS wizard which would be cool if a) it could remember my settings and b) it could be automated.
Should I work the other way around (start from my DBML and generate the DB)? Should I go for some other framework (NHibernate? Can I use some Linq flavor with it?)
Also, I read that LINQ2SQL is already obsolete in favor of Linq to Entities. Does it mean that the ultimate tool supposed to make my life so much better will again make me lose time in the long term?
Thanks for shedding some light.
If you are starting your DB Schema from scratch you could consider "Code-First Development with Entity Framework 4" as outlined by Scottgu.
I have been using this on a new project and am finding it extremely beneficial - especially for testing.
I started with simple POCO classes representing my data, then as the project progressed I would allow EF4 to generate the schema to a "real" DB using my "in-memory" example data ... now I am using a mixture of both in memory POCO (for development and TDD) and auto-generated DB Schema (auto-loaded with more "realistic" data) for demonstrations etc ... so far I am very happy.
There is a lot of opinion over LINQ2SQL and whether it's 'obsolete' or 'discontinued'. But it is still in the .NET framework and a good tool, so if it suit your needs then you should use it. Frankly the Entity Framework is still not perfect and if you don't need the extra flexibility that it affords then it is not worth the pain. If I had a small to midsize project then I would definitely use LINQ2SQL again (and over EF).
As for your question, yes you'll lose any names or different type mappings when you remove and re-add a table. The options that I'm aware of are
Only remove / re-add the table that has changed (not all tables)
Try altering the DBML tables in place, rather than remove / re-add. You can add and remove columns, change column names and data types, add relationships all on the DBML.
I like JcMalta's suggestion of creating objects as classes before rendering into the database, but if you find SQL Studio to be quick to develop with then it might simply be quickest to create tables there are drop them into your DBML. It's a touch annoying to have to change something in a database and the push the changes into your code but the code-gen tools are quite good and take away most of the pain.
You can try CodeSmith/PLINQO to auto-sync DB/code:
http://plinqo.com/
As a follow-up, just wanted to say that I eventually found and fell in love with Huagati DBML/EDMX Tools.
To be totally honest, I must say that the price has significantly increased since I purchased it. I believe it is still worth the money anyway.
And for people who are looking for the same kind of tool for MySQL (or other), DevArt is your friend.
I need to refresh a bunch of EDMX files in my solution. We have disected our tables into groups and each model represents one component or process. However, there are some overlapping tables, which means sometimes I need to refresh/update multiple Entity Models.
Refreshing a group of different entity models in VS 2008 is slow and dangerous. If I miss an out-of-date model, my application won't work
I need to verify that all of the models in my solution are up to date with my development database.
Ultimate solution: How can I script this? Is there an API to Visual Studio for refreshing an EDMX file? I do the exact same thing every time. Can't I program this?
Ok Solution: Can I set something up in Visual Studio to inform me when an Entity Model doesn't match a DB? What is the recommended way to test the model against a DB?
Thanks in advance.
Check out the EDM Generator
http://msdn.microsoft.com/en-us/library/bb387165.aspx
You could put in a pre-build event to regenerate the model.
It's also wise to pre-generate the Views which increases performance substantially.
Hope this helps.
As far as I can tell EdmGen will only work for WPF apps. Since you are looking to update a .EDMX file you will not have access to the xml files which the EdmGen tries to validate.
I would suggest checking the The ADO.NET blog: http://blogs.msdn.com/adonet/archive/2008/06/26/edm-tools-options-part-3-of-4.aspx
They have an explination of how to update an EDMX file but it is pretty involved. Hopefully VS10 will have a better solution for this.
Open the .edmx file in the Model Browser (double click it in VS.Net). Right-click anywhere and choose "Update Model from Database...". The wizard that opens up will show you a limited diff: new tables and deleted tables. But its granularity stops there. It doesn't show changes in fields, for instance.
I'm fairly new to LINQ to SQL, so I could be missing something basic here.
I created a LINQ to SQL layer, generated all the dbml files etc., and created a LINQ query which worked fine. I then made a change to the database, and wanted to get that change reflected in the ORM layer. To do this, I deleted my ORM layer and created a new one (may not be the best way?).
Now my code is not able to see the datacontext object in intellisense and won't compile. I imagine this may be something simple, but I'd also like to understand the bigger picture of how to update the LINQ to SQL ORM layer when the database changes.
Yeah, you don't want to delete your whole DBML file. Open it in the designer, and delete the table that changed. Then drag'n'drop it again from the "Server Explorer" (in the view menu). This will load an updated copy of teh database...
Note that if server explorer is already open while you make the change to the SQL schema, you'll need to refresh server explorer so it has the latest versions.
The drawback to this approach is that if you do customizations to the table in the DBML, those need to be redone. This is an infrequent case for me.
I remember having this issue a bunch. The fix is simple, really. Rebuild your solution! The DataContext and other such classes are generated during a build.
Quite a headache - I wish the DBML tool did this for you when you closed it.
You can also use SQLMetal to update your DBML classes. Some people even write a script or batch file to automate the process.