How to Manually Set Primary Keys in Entity Framework While Avoiding `IDENTITY_INSERT` Errors?

Bypassing Auto-Increment in Entity Framework: A Practical Guide

Entity Framework's automatic primary key generation can be problematic when you need to manually assign key values. This often leads to conflicts, as demonstrated by the error encountered when attempting to override auto-increment behavior.

Initially, the following code was used to prevent Entity Framework from automatically managing the primary key:

modelBuilder.Entity<event>().Property(e => e.EventID).HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);

This, however, resulted in a SqlException: "Cannot insert explicit value for identity column in table 'Events' when IDENTITY_INSERT is set to OFF." This is because the database's IDENTITY_INSERT is disabled, preventing direct insertion of values into identity columns.

A more robust solution utilizes DataAnnotations attributes for a cleaner and more compatible approach, especially with Entity Framework Core:

[Key]
[DatabaseGenerated(DatabaseGeneratedOption.None)]
public int Id { get; set; }

This code snippet declares the Id property as the primary key ([Key]) and explicitly disables automatic value generation ([DatabaseGenerated(DatabaseGeneratedOption.None)]). This allows for manual primary key assignment while maintaining compatibility with the Entity Framework. This method effectively avoids the IDENTITY_INSERT issue and provides a more elegant solution for managing primary keys.

The above is the detailed content of How to Manually Set Primary Keys in Entity Framework While Avoiding `IDENTITY_INSERT` Errors?. For more information, please follow other related articles on the PHP Chinese website!