EF select parents only if all children have certain status - entity-framework

Question

I want to select only those parents whose all children have status = success
I also want to include these children for filtered parents
So the corresponding SQL statement that returns expected result is
select * from Parent p
join Child c on c.ParentId = p.ParentId
where c.Status = 'success'
I want to write the same using EF
var result = await _dbcontext.Parents
.Where(x => x.Children.All(y => y.Status == "success"))
.ToListAsync();
this is not working
Update 1
Sorry the SQL statement above is also not working as expected.
it should only return those parents whose all children have status success. So if parent has 5 children and 4 children have success and 1 does not have success then it should not return that parent
Update 2
I have already disabled the lazy loading
dbContext.Configuration.LazyLoadingEnabled = false;// turn-off loading on-demand
dbContext.Configuration.ProxyCreationEnabled = false;// turn-off dynamic proxy class generation
For the time being lets not include children in the select and only filter the parents. So the following EF query
var result = await _dbcontext.Parents
.Where(x => x.Children.All(y => y.Status == "success"))
.ToListAsync();
generates the following SQL
SELECT
[Extent1].[ParentId] AS [ParentId],
[Extent1].[DocumentName] AS [DocumentName],
[Extent1].[CreatedDateTime] AS [CreatedDateTime],
[Extent1].[ModifiedDateTime] AS [ModifiedDateTime],
FROM [dbo].[Parent] AS [Extent1]
WHERE NOT EXISTS (SELECT
1 AS [C1]
FROM [dbo].[Child] AS [Extent2]
WHERE ([Extent1].[ParentId] = [Extent2].[ParentId]) AND (('success' <> [Extent2].[Status]) OR (CASE WHEN ('success' = [Extent2].[Status]) THEN cast(1 as bit) WHEN ('success' <> [Extent2].[Status]) THEN cast(0 as bit) END IS NULL))
)

Answer 1

Your SQL statement is not correct, you will get all Parents that has at least one childres with the "success" status. But this is not the main point.
As you don't share your model this could it be an eager\lazy load problem. Looks like your EF expression is logically ok. So could you try in this way:
var result = await _dbcontext.Parents.Include(x => x.Children).
.Where(x => x.Children.All(y => y.Status == "success"))
.ToListAsync();

Answer 2

I think i found it. I also have to check if parent has any children. My code was returning parents that does not have any children
var result = await _dbcontext.Parents
.Include(x=>x.Children)
.Where(x => x.Children.Any() && x.Children.All(y => y.Status == "success"))
.ToListAsync();

Answer 3

Why not select all successful Children, and get their Distinct Parents:
var result = dbContext.Children // get all children
.Where(child => child.Status == "success") // keep only the successful ones
.Select(child => child.Parent); // select their parents
.Distinct(); // remove duplicate parents
For this you need to have setup a proper one-to-many relationship in entity framework.
class Parent
{
...
// a parent has many children:
public virtual ICollection<Child> Children {get; set;}
}
class Child
{
...
// A Child belongs to one parent via foreign key
public int ParentId {get; set;}
public virtual Parent Parent {get; set;}
}