We are running webservices which get called to populate and update our database, in one of the functions an EntityReactionType get's filled by the caller of the webservice with the ID's.
EntityReactionType has a composite many-to-one key consisting of Entity and (suprise) ReactionType.
These ID's get filled with the right values and i then want to refresh the object from the database in order to check some values which are set in the database but the user has no knowledge of. In this case: IsStart and IsClosing.
I do all this with the following code: (it's a simplified snipped but the idea should be clear)
I can see the refresh executing the SQL, which is correct and shows that this has IsStart = False and IsClosing = True.
Yet when i look at the object values after the Refresh IsStart = null and IsClosing = False;
//entityReactionTypeRepository.Merge(reaction.EntityReactionType);
entityReactionTypeRepository.Refresh(reaction.EntityReactionType);
if (reaction.IsResolved == true || reaction.EntityReactionType.CloseDispute == true)
{
reaction.IsResolved = true;
reaction.Invoice.IsDisputed = false;
}
I have the Merge line commented out since that is something i found while searching google but changed nothing (idea was that you can't refresh something that isn't transistant but nothing changed, SQL get's executed eitherway but the values do not get updated)
I'm close to making a work around at this time that just creates a detachedcriteria and executes that but i know this should be possible like this.
Greetings,
Folkert
Well today i revisited this problem and i think i understand why it did this, it seems to me when i called the Refresh it kept the original values because in my code before i refresh i also made a Invoice object presistant. The invoice itself doesn't have EntityReactionTypes but in it's object graph it does reference there.
I figure for this reason the session decides to keep the values as they are in the presistent version of the invoice.
So what i did is i put this refresh pretty much at the top of the method and it started to work like it used to and actually pull the values from the database.
Seems odd to me though that it wouldn't change the property values when i did a refresh but this is what it did for me.
Related
I'm trying to gracefully handle extra many to many relationship data in an ATK4 CRUD object. I can manually add the current entry's linked tables as sub CRUD objects while isEditing(), but in doing so i break the 'Add New' button. Code as follows:
function page_projects($p) {
$crud = $this->add('CRUD');
$crud->setModel('Project', null, array('Title', 'School'));
if($crud->grid){
$crud->grid->addPaginator(10);
$crud->grid->addQuicksearch(array('Title','School'));
}
if($crud->isEditing()){
$vForm = $crud->form;
$keywords = $vForm->add('CRUD');
$keywords->entity_name = 'Keyword';
$keywords->setModel(
$crud->model->load($crud->id)->
ref("mProjectKeywords"));
//Other snipped m:m rels
}
}
The issue is simply that $crud->id is not populated (and shouldn't be) when generating a new entry, which means i can't spawn new sub cruds. A workaround is to use:
if($crud->isEditing() && !is_null($crud->id)) {
when checking isEditing(), but this simply stops the sub CRUDS from being instantiated to avoid having load() throw an exception. I've tried looking at loadAny() and tryLoad() and neither do what i want in a many to many context: load a record if one exists, generate a new one otherwise.
Does anyone know a better way of handling this, and if there's not already one in the framework then what's the best angle for attacking this problem?
In this case that's normal behavior because you simply can't create mProjectKeywords record in database table before you INSERT referenced records in parent tables (Project and Keywords).
I do something like if($crud->isEditing() && !is_null($crud->id)) in my projects too.
That means you first have to save (insert) new record in Project and only then sub-CRUD shows up and you can add referenced records in Project edit form (which reloads automatically after you save new project).
This seems like a simple thing and should be part of the base code for Yii, but I can't find a solution anywhere. Here is my scenario.
1) User updates their record (use beforesave to set a cache value, changes with each new save, php unique())
public function beforeSave()
{
Yii::app()->cache->set('userupdate'.$this->id,uniqid());
return parent::beforeSave();
}
2) User data is cached using the cache value in step one as a dependency in the loadModel function of the model.
$model=Users::model()->cache(1800, $dependency)->findByPk($id);
3) User views a page that calls to retrieve their data. Yii evaluates the request to see if the cached valued from step 1 has changed, if it has not pull from cache, if it has pull from db.
While reading this page (http://www.yiiframework.com/doc/guide/1.1/en/caching.data) it has that function if a file date changes, but not one for it a variable changes. Any help in this matter would be great as I am at a loss of how to implement this.
NOTE: I need to use cache to hold the variable as I'm running multiple instances of my application and they need shared over each server and all users (thus session won't work).
After fighting with this I found the solution, don't feel it's completely pretty, but it does work. Any feedback on a cleaner way is much appreciated.
$cache = Yii::app()->cache;
$key1 = 'userupdate'.$id; //main cache value
$key2 = '2userupdate'.$id; //will equal main cache when query is cached
$cache1 = $cache['userupdate'.$id];
$cache2 = $cache['2userupdate'.$id];
$dependency = new CExpressionDependency("Yii::app()->cache->get('$key1') == Yii::app()->cache->get('$key2')");
$model=Users::model()->cache(1800,$dependency)->findByPk($id);
if($cache1 != $cache2)
$cache['2userupdate'.$id] = $cache['userupdate'.$id];
One of the dependency options is CExpressionDependency. You could compare the currently cached beforeSave value to the value you get from the loadModel call.
I am trying get a record updated from database with QueryOver.
My code initially creates an entity and saves in database, then the same record is updated on database externally( from other program, manually or the same program running in other machine), and when I call queryOver filtering by the field changed, the query gets the record but without latest changes.
This is my code:
//create the entity and save in database
MyEntity myEntity = CreateDummyEntity();
myEntity.Name = "new_name";
MyService.SaveEntity(myEntity);
// now the entity is updated externally changing the name property with the
// "modified_name" value (for example manually in TOAD, SQL Server,etc..)
//get the entity with QueryOver
var result = NhibernateHelper.Session
.QueryOver<MyEntity>()
.Where(param => param.Name == "modified_name")
.List<T>();
The previous statement gets a collection with only one record(good), BUT with the name property established with the old value instead of "modified_name".
How I can fix this behaviour? First Level cache is disturbing me? The same problem occurs with
CreateCriteria<T>();
The session in my NhibernateHelper is not being closed in any moment due application framework requirements, only are created transactions for each commit associated to a session.Save().
If I open a new session to execute the query evidently I get the latest changes from database, but this approach is not allowed by design requirement.
Also I have checked in the NHibernate SQL output that a select with a WHERE clause is being executed (therefore Nhibernate hits the database) but don´t updates the returned object!!!!
UPDATE
Here's the code in SaveEntity after to call session.Save: A call to Commit method is done
public virtual void Commit()
{
try
{
this.session.Flush();
this.transaction.Commit();
}
catch
{
this.transaction.Rollback();
throw;
}
finally
{
this.transaction = this.session.BeginTransaction();
}
}
The SQL generated by NHibernate for SaveEntity:
NHibernate: INSERT INTO MYCOMPANY.MYENTITY (NAME) VALUES (:p0);:p0 = 'new_name'.
The SQL generated by NHibernate for QueryOver:
NHibernate: SELECT this_.NAME as NAME26_0_
FROM MYCOMPANY.MYENTITY this_
WHERE this_.NAME = :p0;:p0 = 'modified_name' [Type: String (0)].
Queries has been modified due to company confidential policies.
Help very appreciated.
As far as I know, you have several options :
have your Session as a IStatelessSession, by calling sessionFactory.OpenStatelesSession() instead of sessionFactory.OpenSession()
perform Session.Evict(myEntity) after persisting an entity in DB
perform Session.Clear() before your QueryOver
set the CacheMode of your Session to Ignore, Put or Refresh before your QueryOver (never tested that)
I guess the choice will depend on the usage you have of your long running sessions ( which, IMHO, seem to bring more problems than solutions )
Calling session.Save(myEntity) does not cause the changes to be persisted to the DB immediately*. These changes are persisted when session.Flush() is called either by the framework itself or by yourself. More information about flushing and when it is invoked can be found on this question and the nhibernate documentation about flushing.
Also performing a query will not cause the first level cache to be hit. This is because the first level cache only works with Get and Load, i.e. session.Get<MyEntity>(1) would hit the first level cache if MyEntity with an id of 1 had already been previously loaded, whereas session.QueryOver<MyEntity>().Where(x => x.id == 1) would not.
Further information about NHibernate's caching functionality can be found in this post by Ayende Rahien.
In summary you have two options:
Use a transaction within the SaveEntity method, i.e.
using (var transaction = Helper.Session.BeginTransaction())
{
Helper.Session.Save(myEntity);
transaction.Commit();
}
Call session.Flush() within the SaveEntity method, i.e.
Helper.Session.Save(myEntity);
Helper.Session.Flush();
The first option is the best in pretty much all scenarios.
*The only exception I know to this rule is when using Identity as the id generator type.
try changing your last query to:
var result = NhibernateHelper.Session
.QueryOver<MyEntity>()
.CacheMode(CacheMode.Refresh)
.Where(param => param.Name == "modified_name")
if that still doesn't work, try add this after the query:
NhibernateHelper.Session.Refresh(result);
After search and search and think and think.... I´ve found the solution.
The fix: It consist in open a new session, call QueryOver<T>() in this session and the data is succesfully refreshed. If you get child collections not initialized you can call HibernateUtil.Initialize(entity) or sets lazy="false" in your mappings. Take special care about lazy="false" in large collections, because you can get a poor performance. To fix this problem(performance problem loading large collections), set lazy="true" in your collection mappings and call the mentioned method HibernateUtil.Initialize(entity) of the affected collection to get child records from database; for example, you can get all records from a table, and if you need access to all child records of a specific entity, call HibernateUtil.Initialize(collection) only for the interested objects.
Note: as #martin ernst says, the update problem can be a bug in hibernate and my solution is only a temporal fix, and must be solved in hibernate.
People here do not want to call Session.Clear() since it is too strong.
On the other hand, Session.Evict() may seem un-applicable when the objects are not known beforehand.
Actually it is still usable.
You need to first retrieve the cached objects using the query, then call Evict() on them. And then again retrieve fresh objects calling the same query again.
This approach is slightly inefficient in case the object was not cached to begin with - since then there would be actually two "fresh" queries - but there seems to be not much to do about that shortcoming...
By the way, Evict() accepts null argument too without exceptions - this is useful in case the queried object is actually not present in the DB.
var cachedObjects = NhibernateHelper.Session
.QueryOver<MyEntity>()
.Where(param => param.Name == "modified_name")
.List<T>();
foreach (var obj in cachedObjects)
NhibernateHelper.Session.Evict(obj);
var freshObjects = NhibernateHelper.Session
.QueryOver<MyEntity>()
.Where(param => param.Name == "modified_name")
.List<T>()
I'm getting something very similar, and have tried debugging NHibernate.
In my scenario, the session creates an object with a couple children in a related collection (cascade:all), and then calls ISession.Flush().
The records are written into the DB, and the session needs to continue without closing. Meanwhile, another two child records are written into the DB and committed.
Once the original session then attempts to re-load the graph using QueryOver with JoinAlias, the SQL statement generated looks perfectly fine, and the rows are being returned correctly, however the collection that should receive these new children is found to have already been initialized within the session (as it should be), and based on that NH decides for some reason to completely ignore the respective rows.
I think NH makes an invalid assumption here that if the collection is already marked "Initialized" it does not need to be re-loaded from the query.
It would be great if someone more familiar with NHibernate internals could chime in on this.
Is it possible to do an overload of the actions in the controller? I haven't found any info about it and when I tried, I got this error:
The current request for action 'Create' on controller type 'InterviewController' is >ambiguous between the following action methods:
System.Web.Mvc.ViewResult Create() on type >MvcApplication4.MvcApplication4.InterviewController
System.Web.Mvc.ViewResult Create(Int32) on type >MvcApplication4.MvcApplication4.InterviewController
I've tried to do this on another way and I also get a new error that I can't fix. In fact, I created a new action (called create_client instead of create)
I need 2 ways of creating an "opportunite".
I just call the action, and I receive an empty formular in which I just have to insert data.
From a client's page, I must create an "opportunite" with the client that's already completed when the form is displayed to the user. (there is a need of productivity, the user must perform actions as fast as possible).
In the table "opportunite", I've got a column called "FK_opp_client", which is equal to the column "idClient" from the client's table.
I don't get how I can do the second way.
I've created a new action in the controller.
'
' GET: /Opportunite/Create_client
Function Create_client(idclient) As ViewResult
'Dim FK_Client = (From e In db.client
'Where(e.idClient = idclient)
' Select e.nomCompteClient).ToString()
'ViewBag.FK_client = New SelectList(db.client, "idClient", "nomCompteClient", idclient)
Dim opportunite As opportunite = db.opportunite.Single(Function(o) o.idOpportunite = 5)
opportunite.FK_Client = idclient
ViewBag.FK_Client = New SelectList(db.client, "idClient", "nomCompteClient", opportunite.FK_Client)
Return View(opportunite)
End Function
I've tried a few things to get what I wanted, the last one was to copy what was done in the "Edit" action, but for an empty rank. (so I created an empty rank in my DB). I don't think it was a good idea (imagine someone wants to update the DB where idOpportunite = 5...)
Any better ideas?
If you want to keep those two methods under the same name, you will have to implement an ActionSelectionAttribute to decorate them, or use them with different verbs (for example POST and PUT). Please read more details on action method selection process here (old but still true).
Different approach might be making your parameter optional and make action to check if it has been passed or not (through nullable type).
I'm developing a WCF Data Service with self tracking entities and I want to prevent clients from inserting duplicated content. Whenever they POST data without providing a value for the data key, I have to execute some logic to determine whether that data is already present inside my database or not. I've written a Change interceptor like this:
[ChangeInterceptor("MyEntity")]
public void OnChangeEntity(MyEntity item, UpdateOperations operations){
if (operations == UpdateOperations.Add)
{
// Here I search the database to see if a matching record exists.
// If a record is found, I'd like to use its ID and basically change an insertion
// into an update.
item.EntityID = existingEntityID;
item.MarkAsModified();
}
}
However, this is not working. The existingEntityID is ignored and, as a result, the record is always inserted, never updated. Is it even possible to do? Thanks in advance.
Hooray! I managed to do it.
item.EntityID = existingEntityID;
this.CurrentDataSource.ObjectStateManager.ChangeObjectState(item, EntityState.Modified);
I had to change the object state elsewhere, ie. by calling .ChangeObjectState of the ObjectStateManager, which is a property of the underlying EntityContext. I was mislead by the .MarkAsModified() method which, at this point, I'm not sure what it does.