Bug with Take()

[vvwvann]

I encountered a situation when Take() throws an exception, in a simple code. I assume that this is a bug.

Npgsql.EntityFrameworkCore.PostgreSQL: "5.0.5.1"

            var result = await _context.Categories
                .AsNoTracking()
                .Include(x => x.Products.OrderByDescending(x => x.Discount).Take(4))
                    .ThenInclude(x => x.Preview)
                .OrderBy(x => x.Id)
                .Take(5)
                .ToListAsync();

This code throws an exception with next data

Severity: ERROR
SqlState: 42703
MessageText: column t.PreviewId doesn't exist
Hint: Perhaps a reference to the column was intended "t0.PreviewId".
Position: 3397
File: d:\pginstaller_12.auto\postgres.windows-x64\src\backend\parser\parse_relation.c
Line: 3359
Routine: errorMissingColumn

----------------------------------

Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware[1]
      An unhandled exception has occurred while executing the request.
      System.Exception: error
       ---> Npgsql.PostgresException (0x80004005): 42703: column t.PreviewId doesn't exist

I did not copy the entire stacktrace I think it is not very useful.

It seems to me that I have encountered a bug, since if you remove Take(5) everything will work fine:

            var result = await _context.Categories
                .AsNoTracking()
                .Include(x => x.Products.OrderByDescending(x => x.Discount).Take(4))
                    .ThenInclude(x => x.Preview)
                .OrderBy(x => x.Id)
                .ToListAsync();

I can provide more information if needed.

[smitpatel]

Likely fixed in 6.0

[vvwvann]

Likely fixed in 6.0

What should I do to solve the problem now? Could you please provide a workaround?

[maumar]

I have verified this bug is fixed in current bits. @vvwvann unfortunately there is no good workaround in 5.0. You need to remove the Take on the top level and filter the results on the client.