Performance Giveaways

All credits belong to Waldo. His session on BC Tech Days 2022 was refreshing and informative.

You should check his new Business Central Performance Tool:

https://github.com/waldo1001/waldo.BCPerfTool

If you want to read more about that cool guy, just check his blog https://www.waldo.be/

Our TOP 5 "Performance"-Giveaways:

1. Check if record is filled before you fire "DeleteAll":

AssemblyCommentLine.SetCurrentKey("Document Type", "Document No.");
AssemblyCommentLine.SetRange("Document Type", "Document Type");
AssemblyCommentLine.SetRange("Document No.", "No.");
if not AssemblyCommentLine.IsEmpty() then
  AssemblyCommentLine.DeleteAll();

2. Don't load the whole record. Load always a subset by using "SetLoadFields":

Item.SetLoadFields(Item."Item Category Id", Item."Item Category Code");
Item.SetRange(Item."Item Category Code", '');
if Item.FindSet() then
  repeat
    Item2 := Item;
    if ItemCategory.GetBySystemId(Item2."Item Category Id") then begin
      Item2."Item Category Code" := ItemCategory."Code";
      Item2.Modify();
    end;
  until Item.Next() = 0;

3. Calculating flowfields always outside the loop by using SetAutoCalcFields:

ConfigPackageTable.SetAutoCalcFields("Table Name");
if ConfigPackageTable.FindSet() then
    repeat
      if not HideDialog then
        ConfigProgressBar.Update(ConfigPackageTable."Table Name");

      ExportConfigTableToXML(ConfigPackageTable, PackageXML);
    until ConfigPackageTable.Next() = 0;

4. Using the right keys in your tables and using IncludedFields and SumIndexFields

key(Key1; "Vendor No.", "Posting Date")
{
  IncludedFields = "Currency Code", "Amount to Apply", Open;
}

or

key(Key2; "Vendor No.", "Posting Date")
{
  SumIndexFields = "Purchase (LCY)";
}

5. Use TextBuilder to append substrings instead of using Text variable

procedure ReadAsTextWithSeparator(InStream: InStream; LineSeparator: Text)
var
  Tb: TextBuilder;
  Line: Text;
  begin
    InStream.ReadText(Line);
    Tb.Append(Line);
    while not InStream.EOS do begin
      InStream.ReadText(Line);
      Tb.Append(LineSeparator);
      Tb.Append(Line);
    end;
  end;