Framework the Entity Core 3.0 Preview 6 and Framework the Entity 6.3 Preview 6 has been released , by NuGet.Org get to use.
Following is a brief new features.
EF Core 3.0 Preview 6 New Features
According to official reports, in recent months, their work focused on EF Core achieve new LINQ 3.0 on. Although the work has not been completed, and many of the intended function is also not yet enabled, but still it is necessary to publish this version, because if there is no new realization integrated into the main branch of the code base, the team can not make more progress.
Query aspects of change
preview 6 in some significant aspects of LINQ implement new restrictions, these restrictions affect the execution of any application other than the most simple queries.
Temporary restrictions: memory database and Cosmos DB for supplying the program does not work in this preview
In the initial stage of switching to new implementation, the database and memory functions Cosmos DB supplied program is corrupted, if there are shoes code depends on these procedures, it is recommended to skip preview 6.
Temporary restrictions: aspects query transformation does not apply to a relational database, use the following query any of these structures is probably not the correct conversion or execution
- Has type
- Collect reference prediction
- GroupBy operator
- Comparison of equality between entities
- Querytags
- Global Query filter
Destructive changes: no longer assess the LINQ query on a client
This is actually one of the main motivations team to build the new LINQ implemented in EF Core 3.0 in.
Prior to this release of EF Core, regardless of the position in the query, the query can not be translated into SQL expression is automatically evaluated on the client. This makes it difficult to predict performance problems. This makes it difficult to predict performance problems, particularly when translation is not a predicate expression used in a large amount of data and eventually filter on the client, every time we introduce a new translation feature will cause compatibility problems.
In the new implementation, support only (top-level projection) assess the client's top projection expression in the query. For details, please see the full description of the major changes .
Destructive changes: Existing FromSql overload has been renamed FromSqlRaw and FromSqlInterpolated, and can only be used in the root directory of the query: Please change the document read more details about it .
Switch to the Microsoft.Data.SqlClient
As as recently announced , SQL Server in ADO.NET development of supplying the program has been transferred to this new package. EF Core supply for SQL Server is now using the new software package to connect to a SQL Server database.
DbContext scaffolding improvements
Now supports:
- No keys scaffolding entity
- Scaffolding entity from the database view
DbContextScaffolding from Azure SQL Data Warehouse- The new
dotnet ef dbcontext scriptcommand generates SQL script command is equivalent to calling theEnsureCreated() - The new Package Manager console command function,
Get-DbContextused inDbContextthe list to show the type of applications available
EF 6.3 Preview 6 New Features
Since the preview 5 major changes
When not registered DbProviderFactories, automatic positioning the System.Data.SqlClient . This means that no longer need to register before you start using SqlClient EF for the solution (workaround).
EF 6 Core test being passed to the .NET : team updated infrastructure, so that existing tests can be run on the .NET Core. This enabled them to identify and fix problems in production code, as well as issues .NET Core 3.0 Preview 6 has not yet been fixed.