I have 2 web applications which are let's say Legacy1 and New1. I have separate DbContext for both applications and separate databases.
Now I want to migrate data from the Legacy1 database to the New1 database. I cannot simply use copy database or export database options in SQL Server. Entities are different and I need to incorporate some logic while migrating data.
I have decided to use .Net Core Console (.Net Framework) project to do this. Do I have to add both DbContexts to this project? Also all the entities which I want to map and do the migration or is there any other way to achieve this.
Finally i found a simple approach to achieve that. I used EF DB First approach to generate edmx files for source and target databases. Which gives me access to corresponding Entities as well.
I Queried source database using source dbcontext and manipulated data as per the requirements and inserted into target database using target dbcontext. I used AutoMapper to map source entities to Target entities.
It was much simpler than i thought earlier. Hope it helps others having similar scenario.
Related
My team has inherited a database application that contains hundreds of tables. The application uses Entity Framework and takes a database first approach for development. Our current process is to pull a table or two at a time into the edmx using the Update Model From Database... tool.
We are considering making a new API with .Net Core, but as far as I can tell from the research I have done, there is no equivalent process in the Entity Framework Core tools. The closest thing I can find is to reverse engineer the entire database with Scaffold-DbContext, and then use migrations for all future database changes. We can't scaffold the entire database, because some of the tables have errors, and fixing all those errors is not a viable option for us right now.
I have found that I can supply a list of tables that I want scaffolded with the initial Scaffold-DbContext call, but I'm not sure if migrations can be used in a similar way to the Update Model From Database... tool. Can I use migrations to add tables that already exist in our database? If not, what other options should I be looking at?
This might be a duplicate but I couldn't find appropriate solution,
Server:
SQL Server
Entity Framework
WCF Service
Client
SQLite
Entity Framework for SQLite
WPF
Requirements
I've few common tables in the server and in the client with same table name and same column names.
My task is to delete the data from the client tables and copy the data from the server tables by calling it through my WPF application.
Possible Solutions
Using Microsoft's Sync framework (but data providers are different
so, it may or may not work)
Using traditional approach (removing entity framework) & use Datasets instead.
Are there any better solutions to achieve this Sync functionality?
I've currently got an ASP.NET MVC project, with three C# Class Libraries for Data Access, Settings and an Entity Framework Code First project.
I am currently trying to add a SQL Database Project to my solution so that I can manage my database more closely and add extra items that entity framework doesn't deal with.
I have searched around for integration options and can't find anything more helpful than going the DB first route and updating an edmx model from that.
How would I go about integrating my code first entity framework project with my SQL database project in a way that lets me edit the tables with code first and manage stored procedures and the rest with the database project.
If this is possible, is there any particular way to get these to deploy without conflicting?
Thanks!
I would like to know what is the advisable approach on creating a project with multiple database using entity framework.
My current solution projects looks like this.
SystemName.Data // Points to Database1
SystemName.Core // Points to Database1
SystemName.Database2.Data
SystemName.Database2.Core
SystemName.Database3.Data
SystemName.Database3.Core
SystemName.Business
SystemName.UI
Should I put the all the Data and Core assembly in one project?
Should I also create different business projects for each database?
Thanks in advance!
In EntityFramework 6 (EF6), you can use multiple contexts on the same database. In EF5, a single user model (DbContext) is managed by only one database instance.
So, the multiple DbContexts can be in different projects, and use the same database instance in EF6.
Update
The databases used by the DbContext could be decided by app.config (or web.config). So, I prefer to put my sub-classes of DbContext into different projects according to their purposes. If the database maximum size is considered, like 10GB per database, then put one DbContext to one database might be a good choice. But in EF6, the DbContext could be considered as a plugin. If the application needs an extension to gain more abilities, then an extra DbContext will create necessary database for the extension. Some day the extension is not useful, and it needs to be uninstalled, then some tables in the same database will be dropped.
I started a project and use Entity Framework 5.
Now I created a database on my SQL Server Express with all tables.
Further I created the DbContext with a fluent mapping.
What is better, the fluent mappings or the .edmx mapping files?
The database is now on the SQL Server but I want support also SQL local db.
Is there a way to tell the EF that I want to use a SQL local db?
Should I ship the whole database within the setup or better to create the database on startup of my application? How can I use EF to create the database (SQL server or SQL local db)?
Every useful help would be appreciated.
If you are using EF5 I would stay away from edmx.
You could reverse engineer your model from database using Entity Framework Power Tools.
Than you can customize your model using either Data Annotations or fluent mappings.
If you use EF5 code first it can create database automatically for you if not present, however that would not work very well on subsequent upgrades (it can recreate database but then you will use or your existing data). The options you could use, is either EF migrations, where you can specify in fluent-like languagage the modifications that were made to your database or use Database Project in Visual Studio, where you can store all your schema in source control and then generate database upgrade scripts betweeen releases.