Hi I need to compare two objects in doctrine. I have customer repository and entity. This is my code,
public function index(CarAdRepository $carAdRepository, CustomerRepository $customerRepository): Response {
$cus = $customerRepository->findAll();
$customer = new Customer();
$customer->setTitle('Mr');
$customer->setName('aaa');
$customer->setLastName('bbb');
if($customer == $cus[0]){
echo 'ddd';
}else{
echo 'no';
}
}
in my table I have this values,
But I always get no. It would be great if someone can help
Doctrine implements IdentityMap pattern that ensures that you're always receiving same object for same database row, but only if it was loaded from identity map.
In your case you're comparing some arbitrary object with entity fetched from database using PHP comparison operator. In other words you're checking if 2 objects are equal, but there is no such built-in functionality in PHP.
You have to implement objects comparison function by yourself to achieve your goal because actual comparison logic may vary.
UPDATE:
Simplest example of comparison in your case is property-by-property comparison:
private function compare(Customer $a, Customer $b)
{
return $a->getTitle() === $b->getTitle() &&
$a->getName() === $b->getName() &&
$a->getLastName() === $b->getLastName();
}
It also may be worth to move this method directly into Customer entity with name like isEqual().
It is also possible to implement more generic approach by using reflection, but it may bring certain level of complexity in a case if some non-trivial comparison will need to be involved.
Related
I'm using SQL Server and Entity Framework Core. My table has multiple primary keys and I have to filter many rows at the same time. I'd like to known what's the best approach. I'm trying to aggregate multiple or statements at the where clause, but it's not working. Either it fails to filter or Entity Framework says it cannot convert the LINQ expression to a valid SQL.
To make it simple, let's say my entity has two primary keys.
// WORKS BUT ONLY FOR INPUTS OF LENGTH 2!
public async Task<IList<MyEntity>> GetById(IList<MyEntity> entities)
{
var query = from entity in Context.MyEntity
where (entity.PkNumberOne == entities[0].PkNumberOne && entity.PkNumberTwo == entities[0].PkNumberTwo) ||
(entity.PkNumberOne == entities[1].PkNumberOne && entity.PkNumberTwo == entities[1].PkNumberTwo)
select entity;
return await query.AsNoTracking().ToListAsync();
}
This approach works, but I need to iterate over the entities list.
I have also tried using the method .Any, but the Entity Framework could not translate the expression to valid SQL.
// DOES NOT WORK!
var query = from entity in Context.MyEntity
where entities.Any(e => (entity.PkNumberOne == e.PkNumberOne) && (entity.PkNumberTwo == e.PkNumberTwo))
select entity;
Somehow, I need to programmatically create the fallowing SQL statement for N elements.
SELECT *
FROM MyEntity
WHERE
(PkNumberOne = "Obj1Pk1" AND PkNumberTwo = "Obj1Pk2") OR
(PkNumberOne = "Obj2Pk1" AND PkNumberTwo = "Obj2Pk2") OR
...
(PkNumberOne = "ObjNPk1" AND PkNumberTwo = "ObjNPk2")
Maybe this is not the best approach. If so, please, what should I be doing differently? Is there a better way to filter rows of tables containing composed primary keys?
I'm using API Platform 3 and Gedmo's Softdeleteable Extension. For my entities, I'm using Extensions to add $queryBuilder->andWhere('o.deletedAt IS NULL') to all queries.
This is working fine, but when using OneToMany relations, API Platform doesn't use these extensions and therefor shows 'softdeleted' entities.
Let's take a slightly modified example from their documentation:
#[ApiResource]
class User
{
#[ORM\OneToMany]
#[Serializer\Groups(['user'])]
public Collection $offers;
}
/api/offers/1 correctly shows a 404, because it has been softdeleted. But /api/users/1 shows something like this:
{
username: 'foo',
offers:
{
'#id': "/api/offers/1",
deletedAt: "2022-01-27T12:04:45+01:00"
}
}
How can I change the query that API Platform uses to fetch the relationships?
You have two methods of achieving this.
Filter hydrated objects:
Inside the existing (or completely new) getter:
return $this->offers->filter(function(Offer offer){
return $offer->getDeletedAt() !== NULL;
});
Apply criteria to query:
Again, inside the existing (or completely new) getter:
$criteria = Criteria::create()
->andWhere(Criteria::expr()->eq('deletedAt', NULL));
return $this->offers->matching($criteria);
The Criteria method is preferable if your user could have LOTS of deleted offers - the filtering would be performed on a database level.
Hope this helps.
Btw, both of these methods are well explained in SymfonyCasts tutorials:
https://symfonycasts.com/screencast/api-platform-security/filtered-collection
https://symfonycasts.com/screencast/symfony4-doctrine-relations/collection-criteria
After hours of trying and searching, I think its time to share my problem with you right now.
Problem Definition :
I have a Dictionary of KeyValuePairs(named filterPool) which includes an integer (PropertyID) and a string(McValue). What I am trying to do is filtering products depending on those KeyValuePairs and return them as a DataTable/List.
You may consider this as building dynamic "Where ... And .." clauses as SQL.
Here is the code that I am using :
foreach (KeyValuePair<int, string> filter in filterPool)
{
products = products.Where(i => i.PROPERTYID == filter.Key && i.MCVALUE.Equals(filter.Value));
}
return products.ToDataTable();
The problem is the foreach loop above seems to work only once, for the latest KeyValuePair available in the Dictionary.
As far as I could find on Stackoverflow, the closest solution to my problem was : this one, also using a Dictionary of values for filtering
There must be a way to achieve the goal of filtering using Dictionary and LINQ; or there's a huge thing that I am missing/ignoring to see somehow.
Hope the problem given is clear enough for all,
Thanks
^^
This is a closure issue. You can solve it by making a temporary:
foreach (KeyValuePair<int, string> filterTmp in filterPool)
{
var filter = filterTmp; // Make a temporary
products = products.Where(i => i.PROPERTYID == filter.Key && i.MCVALUE.Equals(filter.Value));
}
return products.ToDataTable();
For details on what's happening, see Eric Lippert's post Closing over the loop variable considered harmful.
Also note that this behavior has changed for C# 5. In C# 5/VS2012, this code would work as expected.
You're overwriting your products collection on every iteration of your foreach. I'm not sure what the data type on your collection is, but you'll want to do something like this in your foreach instead:
products.AddRange(products.Where(i => i.PROPERTYID == filter.Key && i.MCVALUE.Equals(filter.Value)));
I'm not sure if that makes sense, but it seems like you're trying to create a collection full of products that match your filterPool.
I think that it's better solved with aggregate:
return filter
.Aggregate(products, (acc, filter) => acc.Where(i => i.PROPERTYID == filter.Key && i.MCVALUE.Equals(filter.Value)));
.ToDataTable();
Say I have two view models that each have an observable property that represents different, but similar data.
function site1Model(username) {
this.username = ko.observable(username);
....
}
function site2Model(username) = {
this.username = ko.observable(username);
....
}
These view models are independent and not necessarily linked to each other, but in some cases, a third view model creates a link between them.
function site3Model(username) = {
this.site1 = new site1Model(username);
this.site2 = new site2Model(username);
// we now need to ensure that the usernames are kept the same between site1/2
...
}
Here are some options that I've come up with.
Use a computed observable that reads one and writes to both:
site3Model.username = ko.computed({
read: function() {
return this.site1.username(); // assume they are always the same
},
write: function(value) {
this.site1.username(value);
this.site2.username(value);
},
owner: site3Model
}
This will keep the values in sync as long as changes always come through the computed. But if an underlying observable is changed directly, it won't do so.
Use the subscribe method to update each from the other:
site3Model.site1.username.subscribe(function(value) {
this.site2.username(value);
}, site3Model);
site3Model.site2.username.subscribe(function(value) {
this.site1.username(value);
}, site3Model);
This works as long as the observables suppress notifications when the values are the same; otherwise you'd end up with an infinite loop. You could also do the check earlier: if (this.site1.username() !== value) this.site1.username(value); This also has a problem that the observables have to be simple (it won't work right if site1 and site2 themselves are observables).
Use computed to do the subscribe and updates:
site3Model.username1Updater = ko.computed(function() {
this.site1.username(this.site2.username());
}, site3Model);
site3Model.username2Updater = ko.computed(function() {
this.site2.username(this.site1.username());
}, site3Model);
This format allows us to have other dependencies. For example, we could make site1 and site2 observables and then use this.site1().username(this.site2().username()); This method also requires a check for equality to avoid an infinite loop. If we can't depend on the observable to do it, we could check within the computed, but would add another dependency on the observable we're updating (until something like observable.peek is available).
This method also has the downside of running the update code once initially to set up the dependencies (since that's how computed works).
Since I feel that all of these methods have a downside, is there another way to do this that would be simple (less than 10 lines of code), efficient (not run unnecessary code or updates), and flexible (handle multiple levels of observables)?
It is not exactly 10 lines of code (although you could strip it down to your liking), but I use pub/sub messages between view models for this situation.
Here is a small library that I wrote for it: https://github.com/rniemeyer/knockout-postbox
The basic idea is just to create a ko.subscribable and use topic-based subscriptions. The library extends subscribables to add subscribeTo, publishOn and syncWith (both publish and subscribe on a topic). These methods will set up the proper subscriptions for an observable to automatically participate in this messaging and stay synchronized with the topic.
Now your view models do not need to have direct references to each other and can communicate through the pubsub system. You can refactor your view models without breaking anything.
Like I said you could strip it down to less than 10 lines of code. The library just adds some extras like being able to unsubscribe, being able to have control over when publishing actually happens (equalityComparer), and you can specify a transform to run on incoming values.
Feel free to post any feedback.
Here is a basic sample: http://jsfiddle.net/rniemeyer/mg3hj/
Ryan and John, Thank you both for your answers. Unfortunately, I really don't want to introduce a global naming system that the pub/sub systems require.
Ryan, I agree that the subscribe method is probably the best. I've put together a set of functions to handle the subscription. I'm not using an extension because I also want to handle the case where the observables themselves might be dynamic. These functions accept either observables or functions that return observables. If the source observable is dynamic, I wrap the accessor function call in a computed observable to have a fixed observable to subscribe to.
function subscribeObservables(source, target, dontSetInitially) {
var sourceObservable = ko.isObservable(source)
? source
: ko.computed(function(){ return source()(); }),
isTargetObservable = ko.isObservable(target),
callback = function(value) {
var targetObservable = isTargetObservable ? target : target();
if (targetObservable() !== value)
targetObservable(value);
};
if (!dontSetInitially)
callback(sourceObservable());
return sourceObservable.subscribe(callback);
}
function syncObservables(primary, secondary) {
subscribeObservables(primary, secondary);
subscribeObservables(secondary, primary, true);
}
This is about 20 lines, so maybe my target of less than 10 lines was a bit unreasonable. :-)
I modified Ryan's postbox example to demonstrate the above functions: http://jsfiddle.net/mbest/vcLFt/
Another option is to create an isolated datacontext that maintains the models of observables. the viewmodels all look to the datacontext for their data and refer to the same objects, so when one updates, they all do. The VM's dependency is on the datacontext, but not on other VMs. I've been doing this lately and it has worked well. Although, it is much more complex than using pub/sub.
If you want simple pub/sub, you can use Ryan Niemyer's library that he mentioned or use amplify.js which has pub/sub messaging (basically a messenger or event aggregator) built in. Both are lightweight and decoupled.
In case anyone needed.
Another option is to create a reference object/observable.
This also handle object that contains multiple observable.
(function(){
var subscriptions = [];
ko.helper = {
syncObject: function (topic, obj) {
if(subscriptions[topic]){
return subscriptions[topic];
} else {
return subscriptions[topic] = obj;
}
}
};
})();
In your view models.
function site1Model(username) {
this.username = syncObject('username', ko.observable());
this.username(username);
....
}
function site2Model(username) = {
this.username = syncObject('username', ko.observable());
this.username(username);
....
}
In RavenDB I can store objects of type Products and Categories and they will automatically be located in different collections. This is fine.
But what if I have 2 logically completely different types of products but they use the same class? Or instead of 2 I could have a generic number of different types of products. Would it then be possible to tell Raven to split the product documents up in collections, lets say based on a string property available on the Product class?
Thankyou in advance.
EDIT:
I Have created and registered the following StoreListener that changes the collection for the documents to be stored on runtime. This results in the documents correctly being stored in different collections and thus making a nice, logically grouping of the documents.
public class DynamicCollectionDefinerStoreListener : IDocumentStoreListener
{
public bool BeforeStore(string key, object entityInstance, RavenJObject metadata)
{
var entity = entityInstance as EntityData;
if(entity == null)
throw new Exception("Cannot handle object of type " + EntityInstance.GetType());
metadata["Raven-Entity-Name"] = RavenJToken.FromObject(entity.TypeId);
return true;
}
public void AfterStore(string key, object entityInstance, RavenJObject metadata)
{
}
}
However, it seems I have to adjust my queries too in order to be able to get the objects back. My typical query of mine used to look like this:
session => session.Query<EntityData>().Where(e => e.TypeId == typeId)
With the 'typeId' being the name of the new raven collections (and the name of the entity type saved as a seperate field on the EntityData-object too).
How would I go about quering back my objects? I can't find the spot where I can define my collection at runtime prioring to executing my query.
Do I have to execute some raw lucene queries? Or can I maybe implement a query listener?
EDIT:
I found a way of storing, querying and deleting objects using dynamically defined collections, but I'm not sure this is the right way to do it:
Document store listener:
(I use the class defined above)
Method resolving index names:
private string GetIndexName(string typeId)
{
return "dynamic/" + typeId;
}
Store/Query/Delete:
// Storing
session.Store(entity);
// Query
var someResults = session.Query<EntityData>(GetIndexName(entity.TypeId)).Where(e => e.EntityId == entity.EntityId)
var someMoreResults = session.Advanced.LuceneQuery<EntityData>(GetIndexName(entityTypeId)).Where("TypeId:Colors AND Range.Basic.ColorCode:Yellow)
// Deleting
var loadedEntity = session.Query<EntityData>(GetIndexName(entity.TypeId)).Where(e =>
e.EntityId == entity.EntityId).SingleOrDefault();
if (loadedEntity != null)
{
session.Delete<EntityData>(loadedEntity);
}
I have the feeling its getting a little dirty, but is this the way to store/query/delete when specifying the collection names runtime? Or do I trap myself this way?
Stephan,
You can provide the logic for deciding on the collection name using:
store.Conventions.FindTypeTagName
This is handled statically, using the generic type.
If you want to make that decision at runtime, you can provide it using a DocumentStoreListner