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IsDeleted flag

As explained in ASP.NET Core in Action, 3e

An IsDeleted flag is an entity property whose value indicates whether the entity should be treated as deleted without removing its database row.

An IsDeleted flag marks an entity as deleted without removing its database row. This soft-delete approach hides records from the application while preserving data and avoiding many referential-integrity problems. section 12.4.4

Use the flag safely by following these steps:

  • Add a Boolean property such as `public bool IsDeleted { get; set; }` to the entity. section 12.4.4
  • Implement deletion as an update: load the entity, set `IsDeleted = true`, and call `SaveChangesAsync()`. section 12.4.4
  • Exclude flagged entities from every query, or configure an EF Core global query filter to apply the condition at the model level. section 12.4.4
  • Treat this as a practical pattern rather than a universal rule; personally identifying information may need to be scrubbed instead. section 12.4.4
Listing 12.10 Marking entities as deleted in EF Core
public async Task DeleteRecipe(int recipeId)
{
    var recipe = await _context.Recipes.FindAsync(recipeId);  #1
    if(recipe is null) {                                      #2
        throw new Exception("Unable to find the recipe");     #2
    }                                                         #2
    recipe.IsDeleted = true;                                  #3
    await _context.SaveChangesAsync();                        #4
}

Shows the complete EF Core delete operation, including entity lookup, flag assignment, and saving the update. section 12.4.4

How ASP.NET Core in Action, 3e covers it

How deep it goes
Explains the property, service operation, query filtering, and limitation for personal information, but not filter configuration details.
Examples
Uses a Recipe entity, an IsDeleted property, DeleteRecipe, and queries that exclude deleted recipes.
What it assumes
Assumes familiarity with entities, database rows, queries, and EF Core DbContext operations.
What you can do after
Operate/configure EF Core to mark entities deleted, persist the change, and prevent flagged records from returning.
How it connects
Connects IsDeleted flags with EF Core, relational databases, foreign-key constraints, and global query filters.
Cover of ASP.NET Core in Action, 3e
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Related concepts

This explainer was generated by Manning's knowledge graph from the text of ASP.NET Core in Action, 3e. The section links point to the parts of the book it draws on.