private async Task <List <Type> > GetMissingCollectionTypesAsync(IMongoDatabase db)
{
HashSet <string> existing = (await db.ListCollectionNames().ToListAsync())
.Where(n => n.StartsWith(Collection.FfdbPrefix))
.ToHashSet();
return(CollectionResolver.GetDocumentTypes()
.Where(t => !existing.Contains(
CollectionResolver.GetName(t)))
.ToList());
}
