使用LINQ根据是否标记某列来筛选ID

Question

I have a database that holds InvoiceID and a column boolean flag called Corrected . I'm trying to use LINQ to filter whether the database contains these IDs (IDs from another list) but if the Corrected flag is set to true, it would not add that ID.

This is simple enough but the issue I am having is that there might be the same object ID more than once in my table and if any of them have the Corrected flag I would like to skip them all.

So far my code only skips the ones that have the flag set to true. So for example, I might have 8 records with the same ID but only 4 of them have the Corrected flag. Ideally I would skip this ID all together. The below code will only skip 4 and still include the other 4.

var uncorrectedIDs = _context.Table1.SelectMany(y => y.Invoices  
                                    .Where(z => invoiceIDsInPeriod.Contains(z.InvoiceId) 
                       && y.Invoices.Any(w => !w.Corrected))));

How can I adapt this to the above specification? Thanks

Answer 1

GroupBy could be one approach

var notCorrected = 
    _context.Table1
            .SelectMany(table => table.Invoices.Where(i => period.Contains(i.InvoiceId))
            .GroupBy(invoice => invoice.Id)
            .Where(group => group.Any(invoice => invoice.Corrected) == false)
            .SelectMany(group => group)
            .ToList();