How to test that lazy loading is working in Entity Framework
1
The context is set up for lazy loading and seems that everything is working properly but:
public void Test_Lazy_Loading() {
using (var context = new MyDbContext()) {
var student = context.Students.First();
var loaded = context.Entry(student).Collection(e => e.Classes).IsLoaded; // returns true
Assert.IsFalse(loaded); // fails
}
}
Does this test mean that CLasses is eager loaded?
What is the best way to test that lazy loading is working?
c# entity-framework unit-testing lazy-loading dbcontext
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
add a comment |
1
The context is set up for lazy loading and seems that everything is working properly but:
public void Test_Lazy_Loading() {
using (var context = new MyDbContext()) {
var student = context.Students.First();
var loaded = context.Entry(student).Collection(e => e.Classes).IsLoaded; // returns true
Assert.IsFalse(loaded); // fails
}
}
Does this test mean that CLasses is eager loaded?
What is the best way to test that lazy loading is working?
c# entity-framework unit-testing lazy-loading dbcontext
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
As a side note: be careful when using theusingstatements with lazy loading. Because after yourusingstatement, you cannot load the related entity lazily because the db is disposed and so the Eager Loading would be a better choice here. Reading this answer also could be helpful stackoverflow.com/a/34628138/2946329
– S.Akbari
Nov 18 '18 at 10:29
No, it indicates thatClassesis loaded. But I don't see howcontext.Students.First()could do that. On the face of it eager loading (or lazy loading) shouldn't happen here. Maybe you triggered lazy loading in the debugger.
– Gert Arnold
Nov 18 '18 at 11:23
@GertArnold Sorry "students" was a typo I meant "classes". I mean since lazy loading is enabled,thevirtual IList<Class> Classesshould not be loaded since I haven't accessed it yet. Am I wrong?
– roozbeh S
Nov 18 '18 at 12:23
That's correct. And it shouldn't have been loaded by eager loading either. So to me it's unclear how the collection can be marked as loaded at that point if the code runs without debugging. If anything it must be lazy loading because eager loading always happens by explicitly callingInclude. Maybe something in theMyDbContextclass or theStudentclass.
– Gert Arnold
Nov 18 '18 at 12:30
You mean maybe there is a property or method in Student class that invokes loading? something likepublic int numClasses { get { return Classes.Count;}}?
– roozbeh S
Nov 18 '18 at 14:09
add a comment |
1
1
1
The context is set up for lazy loading and seems that everything is working properly but:
public void Test_Lazy_Loading() {
using (var context = new MyDbContext()) {
var student = context.Students.First();
var loaded = context.Entry(student).Collection(e => e.Classes).IsLoaded; // returns true
Assert.IsFalse(loaded); // fails
}
}
Does this test mean that CLasses is eager loaded?
What is the best way to test that lazy loading is working?
c# entity-framework unit-testing lazy-loading dbcontext
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
The context is set up for lazy loading and seems that everything is working properly but:
public void Test_Lazy_Loading() {
using (var context = new MyDbContext()) {
var student = context.Students.First();
var loaded = context.Entry(student).Collection(e => e.Classes).IsLoaded; // returns true
Assert.IsFalse(loaded); // fails
}
}
Does this test mean that CLasses is eager loaded?
What is the best way to test that lazy loading is working?
c# entity-framework unit-testing lazy-loading dbcontext
c# entity-framework unit-testing lazy-loading dbcontext
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
edited Nov 18 '18 at 12:19
roozbeh S
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
asked Nov 18 '18 at 10:25
roozbeh Sroozbeh S
8481411
8481411
As a side note: be careful when using theusingstatements with lazy loading. Because after yourusingstatement, you cannot load the related entity lazily because the db is disposed and so the Eager Loading would be a better choice here. Reading this answer also could be helpful stackoverflow.com/a/34628138/2946329
– S.Akbari
Nov 18 '18 at 10:29
No, it indicates thatClassesis loaded. But I don't see howcontext.Students.First()could do that. On the face of it eager loading (or lazy loading) shouldn't happen here. Maybe you triggered lazy loading in the debugger.
– Gert Arnold
Nov 18 '18 at 11:23
@GertArnold Sorry "students" was a typo I meant "classes". I mean since lazy loading is enabled,thevirtual IList<Class> Classesshould not be loaded since I haven't accessed it yet. Am I wrong?
– roozbeh S
Nov 18 '18 at 12:23
That's correct. And it shouldn't have been loaded by eager loading either. So to me it's unclear how the collection can be marked as loaded at that point if the code runs without debugging. If anything it must be lazy loading because eager loading always happens by explicitly callingInclude. Maybe something in theMyDbContextclass or theStudentclass.
– Gert Arnold
Nov 18 '18 at 12:30
You mean maybe there is a property or method in Student class that invokes loading? something likepublic int numClasses { get { return Classes.Count;}}?
– roozbeh S
Nov 18 '18 at 14:09
add a comment |
As a side note: be careful when using theusingstatements with lazy loading. Because after yourusingstatement, you cannot load the related entity lazily because the db is disposed and so the Eager Loading would be a better choice here. Reading this answer also could be helpful stackoverflow.com/a/34628138/2946329
– S.Akbari
Nov 18 '18 at 10:29
No, it indicates thatClassesis loaded. But I don't see howcontext.Students.First()could do that. On the face of it eager loading (or lazy loading) shouldn't happen here. Maybe you triggered lazy loading in the debugger.
– Gert Arnold
Nov 18 '18 at 11:23
@GertArnold Sorry "students" was a typo I meant "classes". I mean since lazy loading is enabled,thevirtual IList<Class> Classesshould not be loaded since I haven't accessed it yet. Am I wrong?
– roozbeh S
Nov 18 '18 at 12:23
That's correct. And it shouldn't have been loaded by eager loading either. So to me it's unclear how the collection can be marked as loaded at that point if the code runs without debugging. If anything it must be lazy loading because eager loading always happens by explicitly callingInclude. Maybe something in theMyDbContextclass or theStudentclass.
– Gert Arnold
Nov 18 '18 at 12:30
You mean maybe there is a property or method in Student class that invokes loading? something likepublic int numClasses { get { return Classes.Count;}}?
– roozbeh S
Nov 18 '18 at 14:09
As a side note: be careful when using the
using statements with lazy loading. Because after your using statement, you cannot load the related entity lazily because the db is disposed and so the Eager Loading would be a better choice here. Reading this answer also could be helpful stackoverflow.com/a/34628138/2946329– S.Akbari
Nov 18 '18 at 10:29
As a side note: be careful when using the
using statements with lazy loading. Because after your using statement, you cannot load the related entity lazily because the db is disposed and so the Eager Loading would be a better choice here. Reading this answer also could be helpful stackoverflow.com/a/34628138/2946329– S.Akbari
Nov 18 '18 at 10:29
No, it indicates that
Classes is loaded. But I don't see how context.Students.First() could do that. On the face of it eager loading (or lazy loading) shouldn't happen here. Maybe you triggered lazy loading in the debugger.– Gert Arnold
Nov 18 '18 at 11:23
No, it indicates that
Classes is loaded. But I don't see how context.Students.First() could do that. On the face of it eager loading (or lazy loading) shouldn't happen here. Maybe you triggered lazy loading in the debugger.– Gert Arnold
Nov 18 '18 at 11:23
@GertArnold Sorry "students" was a typo I meant "classes". I mean since lazy loading is enabled,the
virtual IList<Class> Classes should not be loaded since I haven't accessed it yet. Am I wrong?– roozbeh S
Nov 18 '18 at 12:23
@GertArnold Sorry "students" was a typo I meant "classes". I mean since lazy loading is enabled,the
virtual IList<Class> Classes should not be loaded since I haven't accessed it yet. Am I wrong?– roozbeh S
Nov 18 '18 at 12:23
That's correct. And it shouldn't have been loaded by eager loading either. So to me it's unclear how the collection can be marked as loaded at that point if the code runs without debugging. If anything it must be lazy loading because eager loading always happens by explicitly calling
Include. Maybe something in the MyDbContext class or the Student class.– Gert Arnold
Nov 18 '18 at 12:30
That's correct. And it shouldn't have been loaded by eager loading either. So to me it's unclear how the collection can be marked as loaded at that point if the code runs without debugging. If anything it must be lazy loading because eager loading always happens by explicitly calling
Include. Maybe something in the MyDbContext class or the Student class.– Gert Arnold
Nov 18 '18 at 12:30
You mean maybe there is a property or method in Student class that invokes loading? something like
public int numClasses { get { return Classes.Count;}}?– roozbeh S
Nov 18 '18 at 14:09
You mean maybe there is a property or method in Student class that invokes loading? something like
public int numClasses { get { return Classes.Count;}}?– roozbeh S
Nov 18 '18 at 14:09
add a comment |
0
active
oldest
votes
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53359848%2fhow-to-test-that-lazy-loading-is-working-in-entity-framework%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
draft saved
draft discarded
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53359848%2fhow-to-test-that-lazy-loading-is-working-in-entity-framework%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
As a side note: be careful when using the
usingstatements with lazy loading. Because after yourusingstatement, you cannot load the related entity lazily because the db is disposed and so the Eager Loading would be a better choice here. Reading this answer also could be helpful stackoverflow.com/a/34628138/2946329– S.Akbari
Nov 18 '18 at 10:29
No, it indicates that
Classesis loaded. But I don't see howcontext.Students.First()could do that. On the face of it eager loading (or lazy loading) shouldn't happen here. Maybe you triggered lazy loading in the debugger.– Gert Arnold
Nov 18 '18 at 11:23
@GertArnold Sorry "students" was a typo I meant "classes". I mean since lazy loading is enabled,the
virtual IList<Class> Classesshould not be loaded since I haven't accessed it yet. Am I wrong?– roozbeh S
Nov 18 '18 at 12:23
That's correct. And it shouldn't have been loaded by eager loading either. So to me it's unclear how the collection can be marked as loaded at that point if the code runs without debugging. If anything it must be lazy loading because eager loading always happens by explicitly calling
Include. Maybe something in theMyDbContextclass or theStudentclass.– Gert Arnold
Nov 18 '18 at 12:30
You mean maybe there is a property or method in Student class that invokes loading? something like
public int numClasses { get { return Classes.Count;}}?– roozbeh S
Nov 18 '18 at 14:09