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Tag: ef-core

79 posts · Page 2 of 8

2026-09-12 comparison ef-core ef-core-11

Native json column vs nvarchar(max) for storing JSON in SQL Server with EF Core 11

Use the native json type on SQL Server 2025 and Azure SQL: EF Core 11 gets JSON_CONTAINS, typed JSON_VALUE, in-place modify() and JSON indexes out of it. Stay on nvarchar(max) for SQL Server 2019/2022, legacy tooling, or a schema you must be able to roll back.

2026-09-10 errors ef-core ef-core-11

Fix: PublishAot plus EFOptimizeContext exhausts memory during an EF Core build

EF Core's build-time model generation re-entered MSBuild until RAM ran out. Upgrade Tasks and Design to 10.0.10+, and on EF Core 11 delete EFOptimizeContext.

2026-09-09 errors ef-core ef-core-11

Fix: AS JSON option can be specified only for column of nvarchar(max) type in WITH clause

EF Core emits [col] json '$.path' AS JSON inside OPENJSON WITH, which Azure SQL rejects with Msg 13618. Upgrade to EF Core 10.0.11+, or drop the provider compatibility level to 160.

2026-09-09 errors ef-core ef-core-11

Fix: Complex entry original ordinal '-1' is invalid when saving a ToJson complex collection

Upgrade Microsoft.EntityFrameworkCore to 10.0.10 or later. Before that, growing a nested collection under a second ToJson complex property crashed SaveChanges.

2026-09-09 errors ef-core ef-core-11

Fix: The complex type collection must be initialized to a non-null value

On EF Core 10.0.x, nulling a complex property that holds a two-element collection inside a ToJson complex collection breaks DetectChanges. Fixed in 11.0.0-rc.1.

2026-09-08 errors ef-core ef-core-11

Fix: MissingMethodException 'AbstractionsStrings.ArgumentIsEmpty' after upgrading EF Core Tools

dotnet ef throws MissingMethodException on ArgumentIsEmpty because Tools 10.0.6 stopped pulling a matching Microsoft.EntityFrameworkCore.Design. Pin Design explicitly to your EF Core version.

2026-09-06 ef-core ef-core-11 concurrency

How to use pessimistic locking with UPDLOCK and SELECT ... FOR UPDATE in EF Core 11

EF Core 11 still has no lock API. Here is how to take a real row lock with FromSql: WITH (UPDLOCK, ROWLOCK) on SQL Server, FOR UPDATE on PostgreSQL, the subquery trap that silently widens the lock, NOWAIT and SKIP LOCKED, deadlock retries, and what to do when the row does not exist yet.

2026-09-06 ef-core ef-core-11 value-converters

How to write an EF Core 11 value converter that maps a null in the database to a non-null value in code

EF Core never passes null to a value converter by default. Here is the internal convertsNulls constructor that changes that, the IsRequired(false) call it depends on, why it cannot work at all for enums and other value types, the WHERE col = NULL trap it creates, and the two patterns that do the job without an internal API.

2026-09-05 ef-core dotnet-11 csharp

What is an EF Core interceptor and when do I need one?

An EF Core interceptor is a class EF calls before and after operations like executing a command or SaveChanges, and it can modify or suppress them, not just observe. Here are the seven interception points in EF Core 11, the registration and lifetime rules, and the cases where a query filter or plain logging is the better answer.

2026-08-30 errors ef-core ef-core-11

Fix: 23505: duplicate key value violates unique constraint on a concurrent EF Core insert

The check-then-insert in your handler is not atomic. Catch PostgresException with SqlState 23505, or collapse the whole thing into one INSERT ... ON CONFLICT statement. EnableRetryOnFailure will not help.