C#•10mo ago

❔ Selecting child tables using EF Core

I have the following class hierarchy Enterprise => Company => Site => Department => Container What would be the most efficent way of selecting a container with a given ID using ef core. In my DbContext I only have a reference to the root object, Enterprise Currently I have this mess:

return await _dbContext.Enterprise
    .AsNoTracking()
    .Include(x => x.Companies)
        .ThenInclude(x => x.Sites)
        .ThenInclude(x => x.Departments)
        .ThenInclude(x => x.Containers)
    .SelectMany(x => x.Companies)
    .SelectMany(x => x.Sites)
    .SelectMany(x => x.Departments)
    .SelectMany(x => x.Containers)
    .FirstOrDefaultAsync(x => x.Id == id);

return await _dbContext.Enterprise
    .AsNoTracking()
    .Include(x => x.Companies)
        .ThenInclude(x => x.Sites)
        .ThenInclude(x => x.Departments)
        .ThenInclude(x => x.Containers)
    .SelectMany(x => x.Companies)
    .SelectMany(x => x.Sites)
    .SelectMany(x => x.Departments)
    .SelectMany(x => x.Containers)
    .FirstOrDefaultAsync(x => x.Id == id);

8 Replies

Pobiega•10mo ago

If you only want the container, why start from enterprises? Go directly for container.

Ole•10mo ago

The dbContext only has the enterprise attribute. The other tables are added implecitly

Pobiega•10mo ago

So fix that.

Angius•10mo ago

Pobiega•10mo ago

If you want direct access, add direct access.

Angius•10mo ago

Then you just do

return await _dbContext.Containers
    .Where(c => c.Department.Site.Company.Enterprise.Id == id)
    .ToListAsync();

return await _dbContext.Containers
    .Where(c => c.Department.Site.Company.Enterprise.Id == id)
    .ToListAsync();

Pobiega•10mo ago

That would give you all containers that match a given enterprise Id

Accord•10mo ago

Was this issue resolved? If so, run /close - otherwise I will mark this as stale and this post will be archived until there is new activity.

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❔ Selecting child tables using EF Core