Create Field Parameters in

• 2024-01-27
• Daniel Otykier

Applies to:

• ✔Tabular Editor 2.x
• ✔Tabular Editor 3.x

Script Purpose

If you want to create field parameters in a Power BI model using Tabular Editor or in a Direct Lake model.

Tip

Want to see the script in action, check out this Guy in a Cube video where Patrick LeBlanc explains how to use it step by step.

Script

Select Columns or Measures to create a field parameter table

// Before running the script, select the measures or columns that you
// would like to use as field parameters (hold down CTRL to select multiple
// objects). Also, you may change the name of the field parameter table
// below. NOTE: If used against Power BI Desktop, you must enable unsupported
// features under File > Preferences (TE2) or Tools > Preferences (TE3).
var name = "Parameter";

if(Selected.Columns.Count == 0 && Selected.Measures.Count == 0) throw new Exception("No columns or measures selected!");

// Construct the DAX for the calculated table based on the current selection:
var objects = Selected.Columns.Any() ? Selected.Columns.Cast<ITabularTableObject>() : Selected.Measures;
var dax = "{\n    " + string.Join(",\n    ", objects.Select((c,i) => string.Format("(\"{0}\", NAMEOF('{1}'[{0}]), {2})", c.Name, c.Table.Name, i))) + "\n}";

// Add the calculated table to the model:
var table = Model.AddCalculatedTable(name, dax);

// In TE2 columns are not created automatically from a DAX expression, so 
// we will have to add them manually:
var te2 = table.Columns.Count == 0;
var nameColumn = te2 ? table.AddCalculatedTableColumn(name, "[Value1]") : table.Columns["Value1"] as CalculatedTableColumn;
var fieldColumn = te2 ? table.AddCalculatedTableColumn(name + " Fields", "[Value2]") : table.Columns["Value2"] as CalculatedTableColumn;
var orderColumn = te2 ? table.AddCalculatedTableColumn(name + " Order", "[Value3]") : table.Columns["Value3"] as CalculatedTableColumn;

if(!te2) {
    // Rename the columns that were added automatically in TE3:
    nameColumn.IsNameInferred = false;
    nameColumn.Name = name;
    fieldColumn.IsNameInferred = false;
    fieldColumn.Name = name + " Fields";
    orderColumn.IsNameInferred = false;
    orderColumn.Name = name + " Order";
}
// Set remaining properties for field parameters to work
// See: https://twitter.com/markbdi/status/1526558841172893696
nameColumn.SortByColumn = orderColumn;
nameColumn.GroupByColumns.Add(fieldColumn);
fieldColumn.SortByColumn = orderColumn;
fieldColumn.SetExtendedProperty("ParameterMetadata", "{\"version\":3,\"kind\":2}", ExtendedPropertyType.Json);
fieldColumn.IsHidden = true;
orderColumn.IsHidden = true;

Explanation

Before running the script the user has to select the measures or columns in the TOM Explorer they wish to have in their field parameter table. The selected objects are then inserted into a calculated table which is then configured as a field parameter table automatically.