✅ LINQ GroupBy error

I don't understand what am I missing when trying to perform a simple GroupBy?

@talje since this is a database call use await.

Using .Where() here also

var query = await context.DosimeterAssocation.Where(x=>x.Barcode).ToListAsync();

@Ayymoss this is GroupBy not Where

Certain database provides will be able to translate that GroupBy LINQ method. The one you're using may not work.

I'm using MSSQL

I'll check mine and see if that LINQ works with PostgreSQL

GroupBy didn't work for me either

You could get the data you need then do it in memory

@talje

I tried awaiting, didn't work

Is your method async?

Yeah ofc, it wouldn't compile otherwise

I ask cuz "didn't work" isn't very helpful 😄

But yeah. I'd suggest doing filtering in database query then groupby in memory

if you need everything, then in my screenshot that shows that

I have tried that by calling ToList() before GroupBy(), the result is the same error

Try following what I did using await and async methods

You don't really want to mix them since .ToList is not asynchronous

test is no longer in the database tho, it's just a regular list

Nothing async to be done there

Ya - the EFCore query is async though, second is in memory grouping

On the topic, though: .GroupBy() can't really be translated to LINQ on its own. You'd need to pair it with .Select() and grab just the keys or some of the properties of those keys or some such

I have tried that by calling ToList() before GroupBy(), the result is the same error

I think they're talking about doing .ToList() on the DbSet then .GroupBy()

TIL

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.

/close