Here's the code. Maybe it will show you roughly what I'm doing. LINQPad is a snippet compiler that lays a LINQ-to-SQL layer over a database and allows you to interact with tables at a high level using collections, objects, and properties. I could probably accomplish the same thing by writing the SQL myself, but my SQL-Fu isn't that strong, and I couldn't get the aggregations right in the relationships between Logical Volume > Physical Volume > Document > Page. So I ended up looping through the volumes. It's not as efficient, but it works.

void Main()
{
 var volumes = Vols.Where (v => v.Sourcevol == 0).OrderBy (v => v.Vol_name);
 var TotalEntries = new List<EntryTotal>();
 var now = DateTime.Now;
 var sortIndex = 0;

 foreach (var volume in volumes)
 {
  volume.Vol_name.Dump();
  decimal tmpSize = 0;
  var totalLine = new EntryTotal();
  totalLine.TimeStamp = now;
  totalLine.VolumeName = volume.Vol_name;
  
  var greyPages = Docs.Where (d => d.Img_bpp == 8 && d.Toc.Vol.Sourcevol == volume.Vol_id && d.Toc.Etype == -2);
  
  var grey = (from page in greyPages
   group page by page.Tocid into docGroup
   select new
   {
    key = docGroup.Key,
    size = docGroup.Sum (d => (decimal)d.Img_size + (decimal)d.Lft_size + (decimal)d.Loc_size + (decimal)d.Txt_size)
   }).Distinct();
     
  totalLine.GreyPageCount = greyPages.Count();
  totalLine.GreyDocCount = grey.Count();
  tmpSize = totalLine.GreyDocCount > 0 ? grey.Sum (g => g.size) : 0;
  totalLine.SetGreySize(tmpSize);
  
  var colorPages = Docs.Where (d => d.Img_bpp == 24 && d.Toc.Vol.Sourcevol == volume.Vol_id && d.Toc.Etype == -2);
  
  var color = (from page in colorPages
   group page by page.Tocid into docGroup
   select new
   {
    key = docGroup.Key,
    size = docGroup.Sum (d => (decimal)d.Img_size + (decimal)d.Lft_size + (decimal)d.Loc_size + (decimal)d.Txt_size)
   }).Distinct();
     
  totalLine.ColorPageCount = colorPages.Count();
  totalLine.ColorDocCount = color.Count();
  tmpSize = totalLine.ColorDocCount > 0 ? color.Sum (g => g.size) : 0;
  totalLine.SetColorSize(tmpSize);
  
  var bwPages = Docs.Where (d => d.Img_bpp == 1 && d.Toc.Vol.Sourcevol == volume.Vol_id && d.Toc.Etype == -2);
  
  var bw = (from page in bwPages
   group page by page.Tocid into docGroup
   select new
   {
    key = docGroup.Key,
    size = docGroup.Sum (d => (decimal)d.Img_size + (decimal)d.Lft_size + (decimal)d.Loc_size + (decimal)d.Txt_size)
   }).Distinct();
     
  totalLine.BWPageCount = bwPages.Count();
  totalLine.BWDocCount = bw.Count();
  tmpSize = totalLine.BWDocCount > 0 ? bw.Sum (g => g.size) : 0;
  totalLine.SetBWSize(tmpSize);
  
  var statLine = new LF_LookupTablesTypes.Stats();
  statLine.BWDocCount = totalLine.BWDocCount;
  statLine.BWPageCount = totalLine.BWPageCount;
  statLine.BWSize = totalLine.BWSize;
  statLine.ColorDocCount = totalLine.ColorDocCount;
  statLine.ColorPageCount = totalLine.ColorPageCount;
  statLine.ColorSize = totalLine.ColorSize;
  statLine.GreyDocCount = totalLine.GreyDocCount;
  statLine.GreyPageCount = totalLine.GreyPageCount;
  statLine.GreySize = totalLine.GreySize;
  statLine.TimeStamp = totalLine.TimeStamp;
  statLine.DocCount = totalLine.DocCount;
  statLine.PageCount = totalLine.PageCount;
  statLine.TotalSize = totalLine.TotalSize;
  statLine.VolumeName = totalLine.VolumeName;
  statLine.SortOrder = sortIndex;
  sortIndex++;
  
  LF_LookupTables.Stats.InsertOnSubmit(statLine);
  
  TotalEntries.Add(totalLine);
 }

 var summaryLine = new LF_LookupTablesTypes.Stats();
 summaryLine.BWDocCount = TotalEntries.Sum (te => te.BWDocCount);
 summaryLine.BWPageCount = TotalEntries.Sum (te => te.BWPageCount);
 summaryLine.BWSize = TotalEntries.Sum (te => te.BWSize);
 summaryLine.ColorDocCount = TotalEntries.Sum (te => te.ColorDocCount);
 summaryLine.ColorPageCount = TotalEntries.Sum (te => te.ColorPageCount);
 summaryLine.ColorSize = TotalEntries.Sum (te => te.ColorSize);
 summaryLine.GreyDocCount = TotalEntries.Sum (te => te.GreyDocCount);
 summaryLine.GreyPageCount = TotalEntries.Sum (te => te.GreyPageCount);
 summaryLine.GreySize = TotalEntries.Sum (te => te.GreySize);
 summaryLine.TimeStamp = now;
 summaryLine.DocCount = TotalEntries.Sum (te => te.DocCount);
 summaryLine.PageCount = TotalEntries.Sum (te => te.PageCount);
 summaryLine.TotalSize = TotalEntries.Sum (te => te.TotalSize);
 summaryLine.VolumeName = "Total";
 summaryLine.SortOrder = sortIndex + 1;
 
 LF_LookupTables.Stats.InsertOnSubmit(summaryLine);

 SubmitChanges();

 TotalEntries.Dump();
}

// Define other methods and classes here
class EntryTotal
{
 public DateTime TimeStamp { get; set; }
 public string VolumeName { get; set; }

 public int GreyDocCount { get; set; }
 public int GreyPageCount { get; set; }
 
 private decimal _GreySize;
 
 public void SetGreySize(decimal size)
 {
  _GreySize = size;
 }
 
 public decimal GreySize
 {
  get
  {
   return Math.Round(_GreySize / 1024M / 1024M / 1024M, 2);
  }
 }
 
 public int ColorDocCount { get; set; }
 public int ColorPageCount { get; set; }

 private decimal _ColorSize;
 
 public void SetColorSize(decimal size)
 {
  _ColorSize = size;
 }
 public decimal ColorSize 
 { 
  get
  {
   return Math.Round(_ColorSize / 1024M / 1024M / 1024M, 2);
  }
 }
 
 public int BWDocCount { get; set; }
 public int BWPageCount { get; set; }
 
 private decimal _BWSize;
 
 public void SetBWSize(decimal size)
 {
  _BWSize = size;
 }
 
 public decimal BWSize 
 { 
  get
  {
   return Math.Round(_BWSize / 1024M / 1024M / 1024M, 2);
  }
 }
 
 public int DocCount
 {
  get
  {
   return GreyDocCount + ColorDocCount + BWDocCount;
  }
 }
 
 public int PageCount
 {
  get
  {
   return GreyPageCount + ColorPageCount + BWPageCount;
  }
 }
 
 public decimal TotalSize
 {
  get
  {
   return GreySize + ColorSize + BWSize;
  }
 }
}