Issue: the primary key of the base table is named differently than the the key in the fk table.
Subsonic 3 does not know how to handle that, which is fine, its beta. So I was going to change the Html.ControlFor logic to just grab the table and use the pkname from that:
var fk = db.FindTable(col.ForeignKeyTo.FriendlyName);
However the .ForeignKeyTo is null. Where in the templates does that ITable get populated?
It shouldn't matter at all if the FK is named differently - what SubSonic looks for is a FK relationship - an actual CONSTRAINT in the DB. But the code you show above looks like it comes from a spike I did a long time ago - are you using 3.0.0.3?
We've been out of beta for a long time :)
http://subsonicproject.com
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I can't find any info about this in the documentation, so I will ask here. How does breeze handle database column defaults? I have required columns in my database, but there are also default static values supplied for these in the database column definitions. Normally, I can insert null into these columns, and the new records will get the default. However, breeze doesn't seem to be aware of database column defaults, and the entities that have null in these columns fail validation on saving.
Thanks,
Mathias
Try editing the edmx xml by adding StoreGeneratedPattern = "Computed" attribute to the column with default value in the DB.
Edit:
Actually, before doing editing the xml, try setting the StoreGeneratedPattern property to Computed in the model editor itself.
Update:
This was fixed in Breeze 1.4.6 ( or later), available now.
Original Post:
There is currently in a bug in Breeze that should be fixed in the next release, out in about week. When this fix gets in then breeze will honor any defaultValues it finds in the EntityFramework data model.
One problem though is while it is easy to get 'defaultValues' into a Model First Entity Framework model via the properties editor, it's actually difficult to get it into a Code First EF model, unless you use fluent configuration. Unfortunately, EF ignores the [DefaultValue] attribute when constructing Code First model metadata.
One workaround that you can use now is to poke the 'defaultValue' directly onto any dataProperty. Something like:
var customerType = myEntityManager.metadataStore.getEntityType("Customer");
var fooProperty = customerType.getProperty("foo");
fooProperty.defaultValue = 123;
I am using the code-first approach in Entity Framework 4.0. I have defined an entity class called 'Product' which contains these properties only - ProductId, ProductName and ProductDescription.
However, the table in database called 'Products' has additional columns like ProductAge, ProductWeight, ProductVolume and IsActive. Will updating/inserting using Entity Framework code-first approach still work with a partially defined entity class?
Trivial issue would be inserts to the table if the unmapped columns are not nullable. Otherwise inserts will work fine. Assuming you are not going to recreate the database from your code first model, it should work.
I have a Client entity and PostCode entity in Linq to SQL model. The Clients table in database contains client_postcode column which is a FK column to postalcode column in PostCode table, which is a varchar column primary key for PostCode table.
When updating Client, in my code I do this
// postcode
updating.PostCode = (from p in ctx.PostCodes
where p.postalcode.Equals(client.PostCode.postalcode)
select p).First();
where client object is provided from ASP.NET MVC View form. This code seems to set the PostCode related entity fine. But when calling SubmitChanges() I receive the following exception:
Value of member 'postalcode' of an object of type 'PostCode' changed. A member defining the identity of the object cannot be changed. Consider adding a new object with new identity and deleting the existing one instead.
So I am currently unable to change the related entity. How is that done in Linq to Sql?
UPDATE:
After further review and troubleshooting I found out that the problem is in ASP.NET MVC UpdateModel() call. If I call UpdateModel() to update the existing entity with the edited data, something is wrong with the FK assignement for PostCode. If I don't call UpdateModel and do it by hand, it works.
Any ideas what goes wrong in UpdateModel() that it can't set the relationship to foreign key entities correctly?
I am updating this question and starting a bounty. The question is simplified. How to successfully use L2S and UpdateModel() to work when updating items (with related entities as FK) in ASP.NET MVC Edit views?
It seems to me that you are receiving PostCode.postalcode in the http post request.
Based on how model binding works, the UpdateModel call updates .PostCode.postalcode of the model you are passing to it.
Use this overload to include or exclude specific properties.
Wouldn't updating.client_postcode = client.client_postcode; accomplish what you want?
Client.PostCode should be looked up on seek based on client_postocde.
You can not do what you are trying, you cannot change the Postcode like that.
James' idea is in the right direction.
Updatemodel() takes the matching values from the Formcollection
How do these values come in the Formcollection? What are their keys?
basically there are 2 ways in editing an object.
option 1:
all the value names you want to update have corresponding keys in the Formcollection, which leaves you just to call UpdateModel() of the original object. do SubmitChanges()
option 2:
Get the original object, change it's values manually (because the keys dont correspond) and do SubmitChanges()
you are tying to change a link, you cant do that. you can only edit the updating.client_postcode which in this case is a string?
Can you please copy the whole action here? So I can write some code for you without gambling.
This is entity framework 4.
CurrentProperty.FMVHistories.Add(FMVPresenter.GetFMVHistoryObject());
DataLayer.AccrualTrackingEntities repository = new AccrualTrackingEntities();
repository.Properties.AddObject(CurrentProperty);
repository.SaveChanges();
Right before I call SaveChanges, CurrentProperty has 1 object in its FMVHistories collection, as it should. Right after the save, it has two - the second of which appears to be a copy of the first, both of which have their foreign keys set, properly.
All objects involved here are new. None were loaded in any way.
FMVHistory has a composite key of 3 fields, one of which is the foreign key to the property it's attached to.
Does anyone know why this second FMVHistory object is getting added?
It looks like this was related to how EF was handling dates. The designer of the FMVHistory table made it with a composite key, part of which was a date field. For some reason when EF put in the object, it truncated the seconds and such from the date it inserted, which broke a lot of weird stuff. I ended up killing the composite key and putting in an identity, and everything is great now.
I am developing StudentApp in .NET 3.5 SP1 MVC Application.
I have two tables
Course
CourseID, course_Name
Students
studentID, student_Name, courseID(fk)
Now I made StudentApp.dbml which is having both table as entities.
As Foreign key will not be present in student entity,
I can not display courseID in student model, more over i can not generate add, edit, list views.
So tell me how to display courseID(fk) in student & i also want course name instead.
And also dropdownbox showing course name & storing courseID in edit view .
I'm pretty sure you have to load the foreign reference for each entity. Since I have no idea how you've constructed your API, I'll have to give you a pseudocode'ish example, but I think this is what you need to do.
List<Students> studList = [your_db_facade].SelectStudents() // Or however you retrieve your students
foreach (Students singleStudent in studList)
singleStudent.Context.CourseReference.Load() //CourseReference.Load() should be in the framework
Then you get the CourseID and name from the single student entity like
singleStudent.Course.CourseID
singleStudent.Course.course_Name
It could look slightly different for you, but I think the key to solving your problem is CourseReference.Load().
If your using LINQ-to-SQL and created a DBML file in Visual Studio then the foreign keys can be listed through the Course property in the Student object (automatically generated so since it is a one-to-many relationship from Student). Sort of like this:
var studentCourseIds =
from s in context.Students
select s.Course.CourseID;
Since your goal is to find the coursename then it is already accessible with Student.Course.course_Name.
Can you post your DBML? Also, DBML is used in LINQ to SQL (L2S) - EDMX is the mapping used in the ADO Entity Framework. Are you using LINQ to SQL or the Entity Framework (EF)?
No matter which one you are using - they both support Foreign Keys and you would get a property representing either side of the relationship - you don't need to do anything special (the Foreign Key must exist in the database, of course).
In EF, the foreign keys are called "navigtion properties" and they work a little differently to Foreign Keys in L2S. Nothing major, but updating them and "eager loading" are somewhat different.
Just drop the tables onto the map in the designer in Visual Studio (or generate using command line equivalents if you prefer).
Regarding Foreign Keys and Drop Down Lists (and other UI goodness) - I wrote a couple of blog entries on some approaches which might suit you. One part is located here and part two is located here.
if you create the correct relationship in your SQL server database, then when you add the tables to your DBML designer, the relationships will be copied across also and your code will link up automatically.