I've been researching this for a while and still couldn't find a satisfactory answer for my problem.
I have an entity on my postgres DB (product) that has a ManyToOne relationship with another entity (Dun).
Each product may have N duns.
On my PUT endpoint, the desired behavior would be:
Every time I update a product, it replaces all the duns with the ones provided on the endpoint.
Is there any way to handle it automatically by Hibernate/JPA?
In order to make it easier to test and explain the issue, I've uploaded a project on Github on the following link https://github.com/brunapereira/jpaexample
If there's no way to handle it automatically by JPA, what's the best way to solve it with code?
Thanks in advance,
First, you need to remove Duns by product id, then get the product by id, add the new duns then save back.
Related
I have created a model with a relationship to another model.
I want to send an email with the entry information, afterCreate seems like the place to do so. But it doesn't contain my relationship fields on the model object.
We have an issue about that on GitHub, there is currently not workaround about that.
Alex is re-writing the logic behind the life cycle function, so lot of issue should be fixed on that after the release of the new system.
As of Strapi 3.0.0, the model lifecycles have changed and now afterCreate does contain relationships.
I am trying to achieve one to many relationship. I know how to do basic one to many relationship between requestor id and userid.
My question is How to refer gtlUserId(resourceRequestTable) to gtlUserId (User table) as by default spring is mapping gtlUserId (resourceRequestTable) to userId in user table
It has some Ways.
I think you should give a specific way during all project !
As My experience each many to one must be a Drop Down in Client side .
However in your Table ResourceTypeEntity should be drop down inside ResourceRequesTable when value of option is Id[primary Key].
Also Your table not seems good design why two many to one map to same table? it may cause 3NF problem in DB also pay attention Cascade it when Parent Table related to other Parent is not good Design ,Keep it simple with uni Direction Many to One And force user to delete manually parent is better ,CaseCade Delete when Parent has related to other table will make exception handling and testing too hard.
please take a look https://examples.javacodegeeks.com/enterprise-java/spring/mvc/spring-mvc-dropdown-box-example/
I have 2 models, one called Employee and another one User,
Employee has one field pointing to User, one to one relationship.
My problem is that i need one query method to find the Employee that has the user with certain id. I need to find the Employee with certain User id.
I know the default query methods: .findOne, .findAll, but i need to create one, alright? how i can do that? i searched a lot but probably i am missing something. I didn't found how to do a query like that.
Thanks
Thus far I have referred to this repo as a reference for how to structure my repositories in my Spring project which leverages QueryDSL.
The only "shortcoming" of this example for me is that it does not outline how I might write a Repository which uses a chain of more than one OneToMany relationships. Using this repository as an example/reference, they have a "Customer" repository and for each Customer there are many "Address". I'm unsure how I would use give or take the same patterns they are using, but for a Class which had a OneToMany relationship with Customers. Meaning, how would I handle a Repository for "CustomerGroup" which has a OneToMany relationship with "Customers" which in turn has a one to many relationship with "Addresses".
Some patterns have occurred to me, but not seem elegant/optimal so I'm looking for anyone with experience or insight as to what might be a nice way of solving this problem.
I very much appreciate any help!
Do you mean in order to write WHERE statements based on the relations?
For example if you want to retrieve all customer groups that contain a customer from a specific country, you can simply call
QCustomerGroup.customerGroup.customer.any().addresses.any().country.eq("Germany")
To make this working to need to add
#OneToMany
private Address addresses;
to the Customer entity.
I created an extension for joomla using:
$id=$database->insertid();
I just covered that if two users are logged on to the site will fit together perform two records in the database and then this statement will return in both cases the same value.
in php you can solve this problem with the transactions.
In joomla how do I solve this problem?
If you have a table you are working with that extends JTable then make sure that you included the check out functionality that is optionally a part of that. THis must means adding a couple of fields like what is in the content table. This will prevent two people from editing the same row at the same time which creates a race condition in which one of the other will lose their data.
Please note that both php and joomla functions to return the last insert id rely on the mysql implementation, and mysql returns the last id inserted on the currently open connection so concurrency is not an issue
#iacoposk8 Your are right it might possible that in very rear case. Such time try to add current logged in user id in your sql query or any where so that it doesn't make any confict. I hope you get it what i want to say. Thanks