Is there a way to make Sequelize automatically map model attributes to table columns the same way Eloquent does? I tried not defining properties on Sequelize model the same way I would do it with Eloquent, but it didn't work. I can't seem to find a configuration variable that would enable automatic mapping of the attributes to a table.
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Suppose that I have an app where the models have been created using Django ORM and Django acts like an API for authentication and gives control to the relation model User using its ORM. At the same time, we want to use Express JS to continuously update a field in one the User model for some feature that requires performance. Is it possible to use a JavaScript ORM with Express JS to update such field? If yes, then how?
In the following tutorial tutorial for Golang, the database is created using SQL and a table called go_test_model is created. Then he uses the struct called GoTestModel to create a row in the table go_test_model.
This basically means that if we create an app called api in Django and add in it a model called Example, then to handle that model in Golang we just create a struct called ApiExample and from there we can have CRUD access to the same table, there might be some conflicts in the fields datatypes between GORM and Django ORM but integrity is still applied in the database itself.
So this particular example solves my problem with Golang and can be replicated using Node JS.
You can use Sequelize for using native functions for performing queries instead of writing raw queries.
Also, please refer to Models section to define models.
EF beginner here.
How am I supposed to make changes in database model using Entity Framework?
I mean in DB model like changing datatypes of columns, adding attributes etc.?
E.g. I have string Password property in User table and I want to add [DataType(DataType.Password)] Attribute or [Required] or anything.
How am I supposed to do that? Of course along with applying changes to my DB? I created DB model from mdf local file (detached from mssql studio) using 'EF Designer from database' so I have my emdx model inside Models (asp.net mvc5) with classes for each table and DB MDF in App_Data.
Am I suppose to modify these classes?
Because I can add attributes right there but Diagram doesn't change and DB doesn't change. I guess I have to commit changes somehow.
I'll add that I can't enable migrations:
Creating a DbModelBuilder or writing the EDMX from a DbContext created using Database First or Model First is not supported.
EDMX can only be obtained from a Code First DbContext created without using an existing DbCompiledModel.
I think you are mixing allot of things here.
If you have an EDMX file, then your models are generated at compile time (or you can generate them from right click on the Model.tt file -> Run Custom Tool). So adding attributes to properties in a class representing a model entity will indeed be overwritten the next time you compile. The solution is:
Create another partial class to the generated classes
In the partial class, decorate the class with the [MetadataType] attribute and give it a type of a metadata class. The metadata class is a simple class, with the same properties as the generated class, but a different name, to prevent naming conflicts. From a design point of view, it should be abstract, because you're not supposed to create instances of it, but this is not required.
In the metadata class, decorate the matching properties with the validation and DataType attributes.
To the best of my knowledge, using model-first or database-first doesn't support migrations as in code-first. If you want to make changes to your schema (semi) automatically, I believe your best option is:
Make changes to your model in the EDMX designer
Right-click on the EDMX design surface -> Generate Database from Model.
After selecting the connection to your database, this will generate the SQL to generate your schema. This is a bit clunky, because it will erase your data each time, so you should have a script in place to re-populate your database after each time.
I found this solution for a problem I have: how to generate entities with JPA annotations from a given database.
IntelliJ IDEA 10 generate entity (POJO) from DB model
Now with IntelliJ I'm given the possibility to create relationships between entities manually. Is there a way to generate them automatically as it did with entities?
I used the REFERENCES keyword when needed while creating the database. I suppose there should be an automatic mapping of relationships as well!
When Generating entities from DB Schema in dialog there is an option to 'Show default relationships' which when selected will display FK relationships when selecting tables to generate entities from:
I am deciding how I should create an entity which I pull from a 3rd party api. The concept of my entity requires two API calls, one of which pulls the unique data about the entity, and the other which gives me a full schema of all possible data that could belong to an entity.
I've already written a repository for the entity, but where does the schema map fit in the domain layer if I'm only going to grab it once?
How should the entity hold this schema data?
I'm not familar with the mapper pattern, but does that seem like this is the right use case for it?
If you have schema data and then data then you're dealing with an entity with dynamic properties, akin to a dictionary or hashtable, but with validation.
You could treat the schema data as an entity of its own, that provides the knowledge level to instantiate and validate entities, which lie on the operational level.
Take a look here (pdf) for many related patterns.
What I need is to populate entity from DB view (non-insertable) and make all entity updates to updatable DB table.
Mapping entity to table and writing custom load SQL from view is not an option since in some cases NHibernate still tries to select from table name (when joining this entity, for example).
Mapping entity to view and writing custom data modification queries is not an option since I can not write cross-database sql-insert statement (because of the last inserted identity value selection part).
The only idea I came up with for now is to modify generated SQL statements on-the-fly. I managed to do it with custom interceptor but I don't think that its a good idea (since I intercept every single query, even for other entities). However, I think that it should be possible to change only needed queries using custom IEntityPersister. I created one based on SingleTableEntityPersister, specified it in <class persister="…">, but NHibernate doesn't even want to instantiate it.
Are there any examples of writing custom entity persisters for NHibernate?