Data Access & Databases EF Core Caching Performance

EF Core Second-Level Caching

Mind Map Summary

  • Topic: EF Core Second-Level Caching
  • Definition: A query cache that stores the results of queries in a cache that is shared across multiple DbContext instances. This can significantly improve performance by reducing the number of database queries.
  • How it Works:
    • When a query is executed, the cache is first checked for the results.
    • If the results are in the cache, they are returned from the cache.
    • If the results are not in the cache, the query is executed against the database, and the results are stored in the cache for future use.
  • Popular Library: EFCoreSecondLevelCacheInterceptor
  • Benefits:
    • Improved Performance: Reduces the number of database queries, which can significantly improve performance.
    • Reduced Database Load: Reduces the load on the database server.
  • Considerations:
    • Cache Invalidation: The cache must be invalidated when the underlying data changes.
    • Stale Data: There is a risk of serving stale data if the cache is not invalidated correctly.

Practice Exercise

Integrate a second-level caching provider (like EFCoreSecondLevelCacheInterceptor) into an ASP.NET Core application. Enable caching for a specific query and demonstrate that on the second execution of the query, the data is served from the cache instead of hitting the database.

Answer

1. Install the NuGet Package:

dotnet add package EFCoreSecondLevelCacheInterceptor

2. Configure the Second-Level Cache in Program.cs:

builder.Services.AddDbContext<MyDbContext>((serviceProvider, options) =>
    options.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection"))
           .AddInterceptors(serviceProvider.GetRequiredService<SecondLevelCacheInterceptor>()));

builder.Services.AddEFSecondLevelCache(options =>
    options.UseMemoryCacheProvider()
           .DisableLogging(true)
);

3. Enable Caching for a Query:

// This query will be cached for 60 seconds.
var products = context.Products.Cacheable(CacheExpirationMode.Absolute, TimeSpan.FromSeconds(60)).ToList();

4. Demonstrate Caching:

  • Run the application and execute the query. The first time the query is executed, it will hit the database.
  • Execute the query again within 60 seconds. This time, the query will be served from the cache, and you will not see a database query in the logs.