Join, or where after sau select query acumatica

var imagesSelect = new PXSelectJoin<InventoryItem, LeftJoin<UploadFile, On<InventoryItem.imageUrl, Equal<UploadFile.name>>>>(this);

imagesSelect.Join<LeftJoin<NoteDoc, On<UploadFile.fileID, Equal<NoteDoc.fileID>>>>();

imagesSelect.WhereAnd<Where<InventoryItem.imageUrl, IsNotNull>>();