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Entity Framework - The DbContext of type 'SampleContext' cannot be pooled because it does not have a single public constructor accepting a single parameter of type DbContextOptions.

I was looking at some ways to improve the performance of one of our applications. One of the things I wanted to try was to active DbContext pooling(https://bartwullems.blogspot.com/2018/03/entity-framework-core-20dbcontext.html).

Unfortunately after adding the following lines:

the application started to fail with this exception message:

System.InvalidOperationException: The DbContext of type 'TargetSUContext' cannot be pooled because it does not have a single public constructor accepting a single parameter of type DbContextOptions.

   at Microsoft.EntityFrameworkCore.Internal.DbContextPool`1..ctor(DbContextOptions options)

   at Microsoft.Extensions.DependencyInjection.EntityFrameworkServiceCollectionExtensions.<>c__5`2.<AddDbContextPool>b__5_1(IServiceProvider sp)

   at lambda_method(Closure , IBuildSession , IContext )

Let’s take a look at my DbContext and indeed I had multiple constructors:

I don’t understand why Entity Framework cannot handle this, but I removed the other constructors to make EF happy…

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