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Entering keys manually with Entity Framework

sql
entity-framework
database-integrity
transactions
Anton ShumikhinbyAnton Shumikhin·Oct 13, 2024
TLDR

In Entity Framework (EF), modify the key-generation strategy to none, when you want to assign manual values. Add the [DatabaseGenerated(DatabaseGeneratedOption.None)] attribute for data annotations or configure Fluent API using .ValueGeneratedNever() like so:

Data Annotations:

[Key] [DatabaseGenerated(DatabaseGeneratedOption.None)] public int Id { get; set; } // If I had a penny for every time someone forgot this...

Fluent API:

modelBuilder.Entity<EntityName>() .Property(e => e.Id) .ValueGeneratedNever(); // The magic words to produce your own keys.

Critical Point: Always ensure your manual keys are unique. Duplicates are like doppelgängers - they cause chaos!

Working with custom keys in EF

The auto-incrementing primary keys in EF are not universally application. The wheel of custom key usage turns when you need to integrate with existing systems bearing their own exclusive identification keys or when business requirements demand the usage of specific values.

Customising migrations with EF

One of the interesting facets of dealing with EF migrations is that they allow you to peek under the hood to control finer details, like toggling IDENTITY_INSERT for batch operations.

Avoiding common pitfalls with manual insertion

In the world of EF, expecting the unexpected can save you from surprises. Remember to not insert into IDENTITY columns when IDENTITY_INSERT is set to OFF. EF isn't shy to raise its voice through explicit errors!

Strategies for generating unique manual keys

Ensuring uniqueness of keys

In the world of database integrity, unique keys hold the reign. In manual key assignment, it's no less than a doctrinal practice to ensure that these keys are as unique as snowflakes.

Fighting conflicts with concurrency tokens

Concurrency tokens can be your mighty shield when fighting concurrent updates and inserts, especially when manual keys are a part of the picture.

Embracing transactions

Transactions are the silent heroes of database operations, vouchsafing your manual inserts and ready to save your day with a rollback in case anything fumbles!