DB query is executed with the parameters of the previous query

[linnando]

Steps to reproduce

Minimal solution: https://github.com/linnando/EFCoreTest

Model.cs contains the description of the model copied from https://docs.microsoft.com/en-us/ef/core/index

To reproduce the bug:

1. Execute tests in Deployment.cs (they will apply migrations and seed the test data).
2. Execute tests in MainTest.cs. Each of two tests queries the database twice. After each query, the count of found records is written to the debug trace. The first query looks for a blog with url "test" (which exists in the database) and the second one --- for a blog with url "wrong_url" (which does not). So, the expected output is 1 and 0 (in each test).

The issue

TestGetByQueryableUrl outputs 1 and 1 instead of expected 1 and 0. In the debug mode, I see that in both cases, the same query is sent to the database: "SELECT COUNT(*) FROM [Blogs] AS [blog] WHERE [blog].[Url] IN (N'test')". Although in the second time another parameter "wrong_url" is given, the query is still sent to the database with parameter "test" instead (probably, somehow cached from the previous query).

In contrast, TestGetByEnumerableUrl works correctly (sends correct queries and outputs 1 and 0), although it differs from the first test only in the signature of the auxiliary method (GetBlogsByEnumerableUrl).

Further technical details

EF Core version: 1.1.0
Operating system: Windows 10 Enterprise N
Visual Studio version: VS Enterprise 2015 (14.0.25431.01 Update 3)

[divega]

Assigning this to @anpete for investigation in the 1.1.1 milestone based on the potential severity. We can discuss it next time we triage.

[divega]

@anpete was this fixed pushed to the 1.1.1 branch? Should we reopen the issue?

[anpete]

Yep, re-opened.

[Eilon]

This patch bug is approved. Please use the normal code review process w/ a PR and make sure the fix is in the correct branch, then close the bug and mark it as done.

[divega]

@anpete closing again since the fix is in and approved for the patch. Please reopen if necessary.

[smitpatel]

✅ Verified