An EF Core v7 query:

var results = await _context
  .Customers
  .Join(
    _context.Orders.AsNoTracking(),
    customer => customer.Reference,
    order => order.Reference,
    (customer, order) => new {                // I only want properties in this anonymous type
      Reference       = customer.Reference,
      CustomerId      = customer.Id,
      CustomerName    = customer.Name,
      CustomerAddress = customer.Address,
      OrderId         = order.Id,
      OrderDate       = order.Date,
      OrderValue      = order.Value,
  })
  .AsNoTracking()
  .ToListAsync();

It generates something like this:

SELECT c."Id", c."Reference", c."Name", c."Address",
       o."Id", o."Date", o."Value", o."Reference", o."Discount", o."Operator", o."Store", o."Quantity", o."PaymentType", o."Repeat", o."LastPlaced", o."Warehouse", o."StockCode", o."Supplier"
FROM "Customer" AS c
INNER JOIN "Order" AS o ON c."Reference" = o."Reference"

Notice it includes all properties of the Order entity, not just the ones I used in the projection.

Approach 2: I also tried this in the join:

  // ...
  .Join(
    _context.Orders.AsNoTracking().Select(x => new { x.Reference, x.Id, x.Date, x.Value }),
    // ...

Approach 3: I also tried projecting to this:

// ...
.Join(/*...*/)
.Select(x = new {
  Reference,
  CustomerId,
  CustomerName,
  CustomerAddress,
  OrderId,
  OrderDate,
  OrderValue,
})
// ...

But those approaches also didn’t restrict the results.

What is the correct way to do this?