I have a very small entity framework setup containing only a few related classes/tables and a view. I need to be able to pull a specific record from this view, namely, I need to be able to grab the record that meets two criteria, it has a specific ProfileID and a specific QuoteID.
This line is what's causing the problem:
TWProfileUpchargeTotal upchargeTotals = _context.TWProfileUpchargeTotals.Where(p => p.Profileid == profile.id && p.quoteid == _quote.quoteid).First();
I'm looping through the profiles I know about and getting their information from the view, so profile.id changes each time.
The first time this code executes it gets the correct record from the view.
The second and third (and presumably beyond that) time it executes, it retrieves the exact same record.
Any idea why or what I'm doing wrong here?
Thanks, in advance.
You've been bitten by the LINQ "gotcha" called closure. The following post (and many others) on SO detail this:
closure
What you need to do is declare a variable WITHIN the foreach you've ommited from the above code and assign the profile.id to this and use this in the Where clause.
foreach(Profile profile in ListOfProfiles)
{
var localProfile = profile;
TWProfileUpchargeTotal upchargeTotals = _context.TWProfileUpchargeTotals.Where(p => p.Profileid == localProfile.id && p.quoteid == _quote.quoteid).First();
}
Related
I'm using Play Framework 2 and Ebean. When a user submits a form to edit an existing object in the database, it doesn't save null values. I guess this is to prevent overwriting fields that aren't in the form with null. But how can I let them set fields in the form to null if they need to?
For example, the user edits an Event object. Event.date is 1/1/13. The user sets the Event.date field in the form to empty and submits the form. Inspecting Event.date in the debugger shows its value is null. I save the Event. If I look at the Event in the database, its value is still 1/1/13.
Edit: It seems there is a method for this. The only problem is it doesn't work on nested entities. Any solutions for this?
update(Object bean,Set<String> properties)
Create an ebean.properties file right next to the application.conf file and add this line to it:
ebean.defaultUpdateNullProperties=true
Null properties in Ebean are considered as unloaded, so to prevent accidental nulling properties that shouldn't be nulled, they are just excluded.
Because of this reverting Date (and other fields) to null in Ebean is... hard :). Last time when I had to do the same thing (revert Date) I used second query to do just... nulling the Date (after event.update(Object o)):
public static Result updateEvent(){
Form<Event> eventForm = form(Event.class).bindFromRequest();
// do some validation if required...
Event event = eventForm.get();
event.update(event.id);
if (eventForm.get().date == null){
Ebean
.createUpdate(Event.class, "UPDATE event SET date=null where id=:id")
.setParameter("id", page.id).execute();
}
}
On the other hand, if you are using comparison, for filtering events (always selecting newer than X), you can just set the date to very 'old' value, which also should do the trick. In this case you'll update the object only once.
private static final Date VERY_OLD_DATE = new GregorianCalendar(1, 0, 1).getTime();
public static Result updateEvent(){
Form<Event> eventForm = form(Event.class).bindFromRequest();
Event event = eventForm.get();
if (eventForm.get().date == null){
event.date = VERY_OLD_DATE;
}
event.update(event.id);
}
In this case in your HTML form you will need to clear the value of the form's field (or just send every time date like 0001-01-01), however it can be done easily even with JavaScript.
I'm building a form with Yii that updates two models at once.
The form takes the inputs for each model as $modelA and $modelB and then handles them separately as described here http://www.yiiframework.com/wiki/19/how-to-use-a-single-form-to-collect-data-for-two-or-more-models/
This is all good. The difference I have to the example is that $modelA (documents) has to be saved and its ID retrieved and then $modelB has to be saved including the ID from $model A as they are related.
There's an additional twist that $modelB has a file which needs to be saved.
My action code is as follows:
if(isset($_POST['Documents'], $_POST['DocumentVersions']))
{
$modelA->attributes=$_POST['Documents'];
$modelB->attributes=$_POST['DocumentVersions'];
$valid=$modelA->validate();
$valid=$modelB->validate() && $valid;
if($valid)
{
$modelA->save(false); // don't validate as we validated above.
$newdoc = $modelA->primaryKey; // get the ID of the document just created
$modelB->document_id = $newdoc; // set the Document_id of the DocumentVersions to be $newdoc
// todo: set the filename to some long hash
$modelB->file=CUploadedFile::getInstance($modelB,'file');
// finish set filename
$modelB->save(false);
if($modelB->save()) {
$modelB->file->saveAs(Yii::getPathOfAlias('webroot').'/uploads/'.$modelB->file);
}
$this->redirect(array('projects/myprojects','id'=>$_POST['project_id']));
}
}
ELSE {
$this->render('create',array(
'modelA'=>$modelA,
'modelB'=>$modelB,
'parent'=>$id,
'userid'=>$userid,
'categories'=>$categoriesList
));
}
You can see that I push the new values for 'file' and 'document_id' into $modelB. What this all works no problem, but... each time I push one of these values into $modelB I seem to get an new instance of $modelA. So the net result, I get 3 new documents, and 1 new version. The new version is all linked up correctly, but the other two documents are just straight duplicates.
I've tested removing the $modelB update steps, and sure enough, for each one removed a copy of $modelA is removed (or at least the resulting database entry).
I've no idea how to prevent this.
UPDATE....
As I put in a comment below, further testing shows the number of instances of $modelA depends on how many times the form has been submitted. Even if other pages/views are accessed in the meantime, if the form is resubmitted within a short period of time, each time I get an extra entry in the database. If this was due to some form of persistence, then I'd expect to get an extra copy of the PREVIOUS model, not multiples of the current one. So I suspect something in the way its saving, like there is some counter that's incrementing, but I've no idea where to look for this, or how to zero it each time.
Some help would be much appreciated.
thanks
JMB
OK, I had Ajax validation set to true. This was calling the create action and inserting entries. I don't fully get this, or how I could use ajax validation if I really wanted to without this effect, but... at least the two model insert with relationship works.
Thanks for the comments.
cheers
JMB
Consider the following code.
var items = from i in context.Items
select i;
var item = items.FirstOrDefault();
item.this = "that";
item.that = "this";
var items2 = from i in context.Items
where i.this == "that"
select i;
var data = items2.FirstOrDefault();
context.SaveChanges();
I'm trying to confirm that items2 will not include my modifications to item. In other words, items2's copy of item will not include the unsaved changes.
Have you tried it? =)
By default, your objects are being tracked and cached by the context, so that the objects in your second query actually do reflect changes in the first.
You may want to call context.Items.AsNoTracking() on the one of your two "items" to get the behavior you want.
Edit: Actually, this is a strange question. I just noticed that your items2 hasn't even hit the database yet, since you haven't called ToList() or FirstorDefault(). It remains an IQueryable that will hit the database after your code snippet and will therefore contain the changed value.
HOWEVER, if you call ToList() on items2, you'll encounter the caching scenario I outlined above.
In case of "var item" your query is executed the moment you used FirstOrDefault(). But for var items2 the query is still not executed. Now in your case result of items2 will always be affected by the updates you have done in the first query.
It will contain the modifications, only way to do is create a new context and query the new context.
Using C# 3.5 through VS 2008 and subsonic 2.2.
Anyone know if it's possible to create a subsonic query that essentially has an 'IF' in the middle of it, depending on whether a passed parameter was, for example, greater than zero.
For example, a delete method that has two passed parameters - A and B.
I want something like (pseudo code)
DELETE from Products
Where productId = A
if(B > 0)
{
AND ProductAttributeId = B
}
Obviously it wouldn't need the actual 'IF' clause in there but that's the essence of what I'm trying to do with subsonic. I know I can just have two different queries depending on whether the parameter is there or not but I was wondering if there's a cleaner way of doing it.
Thanks.
That's how I usually do it - it's not two queries, but one SqlQuery with optionally added constraints:
SqlSquery q = DAL.DB.Delete()
.From<DAL.Product()
.Where(DAL.Product.ProductIdColumn).IsEqualTo(A);
if (B > 0)
{
q.And(DAL.Product.ProductAttributeIdColumn).IsEqualTo(B);
}
q.Execute();
There may be a typo, I can't test this right now.
I'm using Symfony 1.2 with Doctrine. I have a Place model with translations in two languages. This Place model has also a nested set behaviour.
I'm having problems now creating a new place that belongs to another node. I've tried two options but both of them fail:
1 option
$this->mergeForm(new PlaceTranslationForm($this->object->Translation[$lang->getCurrentCulture()]));
If I merge the form, what happens is that the value of the place_id field id an array. I suppose is because it is waiting a real object with an id. If I try to set place_id='' there is another error.
2 option
$this->mergeI18n(array($lang->getCurrentCulture()));
public function mergeI18n($cultures, $decorator = null)
{
if (!$this->isI18n())
{
throw new sfException(sprintf('The model "%s" is not internationalized.', $this->getModelName()));
}
$class = $this->getI18nFormClass();
foreach ($cultures as $culture)
{
$i18nObject = $this->object->Translation[$culture];
$i18n = new $class($i18nObject);
unset($i18n['id']);
$i18n->widgetSchema['lang'] = new sfWidgetFormInputHidden();
$this->mergeForm($i18n); // pass $culture too
}
}
Now the error is:
Couldn't hydrate. Found non-unique key mapping named 'lang'.
Looking at the sql, the id is not defined; so it can't be a duplicate record (I have a unique key (id, lang))
Any idea of what can be happening?
thanks!
It looks like the issues you are having are related to embedding forms within each other, which can be tricky. You will likely need to do things in the updateObject/bind methods of the parent form to get it to pass its values correctly to its child forms.
This article is worth a read:
http://www.blogs.uni-osnabrueck.de/rotapken/2009/03/13/symfony-merge-embedded-form/comment-page-1/
It gives some good info on how embedding (and mergeing) forms work. The technique the article uses will probably work for you, but I've not used I18n in sf before, so it may well be that there is a more elegant solution built in?