TabularEditor · mlonsk · Jun 25, 2025
diff --git a/content/common/CSharpScripts/Advanced/script-convert-dlol-to-import.md b/content/common/CSharpScripts/Advanced/script-convert-dlol-to-import.md
@@ -0,0 +1,282 @@
+---
+uid: script-convert-import-to-dlol
+title: Convert Direct Lake on OneLake to import
+author: Morten Lønskov
+updated: 2025-06-25
+applies_to:
+  versions:
+    - version: 2.x
+    - version: 3.x
+---
+# Convert Import to Direct Lake on OneLake
+
+## Script Purpose
+
+This script converts Direct Lake on OneLake (DL/OL) to Import mode tables. As laid out in the [Direct Lake guidance article](xref:direct-lake-guidance), we need to replace the partition(s) on such tables with a single [EntityPartition](https://learn.microsoft.com/en-us/dotnet/api/microsoft.analysisservices.tabular.entitypartitionsource?view=analysisservices-dotnet), which specifies the name and schema of the table/materialized view in the Fabric Lakehouse or Warehouse, while referencing a Shared Expression that uses the [`AzureStorage.DataLake`](https://learn.microsoft.com/en-us/powerquery-m/azurestorage-datalake) (OneLake) connector.
+
+## Prerequisites
+
+You will need the **SQL Endpoint** as well as the **Name** of your Fabric Warehouse or Lakehouse. Both can be found in the Fabric portal. 
+
+You will also need to know the **Schema** of the table/materialized view you wish to connect to.
+
+
+## Script
+
+### Convert Import mode tables to Direct Lake on OneLake
+
+```csharp
+// ===================================================================================
+// Convert Direct Lake on OneLake tables back to Import mode
+// ----------------------------------------
+// This scripts converts the selected or all tables from Direct Lake on OneLake to import
+//  It adds a shared expression named SQLEndpoint and replaces the existing DatabaseQuery if it no longer needed
+// ===================================================================================
+using System;
+using System.Linq;
+using System.Collections.Generic;
+using System.Windows.Forms;
+using System.Drawing;
+
+// -------------------------------------------------------------------
+// 1) Scope‐picker dialog
+// -------------------------------------------------------------------
+public class ScopeSelectionDialog : Form
+{
+    public enum ScopeOption { OnlySelected, All, Cancel }
+    public ScopeOption SelectedOption { get; private set; }
+
+    public ScopeSelectionDialog(int selectedCount, int totalCount)
+    {
+        Text = "Choose tables to convert";
+        AutoSize = true; AutoSizeMode = AutoSizeMode.GrowAndShrink;
+        StartPosition = FormStartPosition.CenterParent;
+        Padding = new Padding(20);
+
+        var layout = new TableLayoutPanel {
+            ColumnCount = 1, Dock = DockStyle.Fill,
+            AutoSize = true, AutoSizeMode = AutoSizeMode.GrowAndShrink
+        };
+        Controls.Add(layout);
+
+        layout.Controls.Add(new Label {
+            Text = $"You have {selectedCount} table(s) selected,\nand {totalCount} Direct Lake table(s) in the model.",
+            AutoSize = true, TextAlign = ContentAlignment.MiddleLeft
+        });
+
+        var panel = new FlowLayoutPanel {
+            FlowDirection = FlowDirection.LeftToRight,
+            Dock = DockStyle.Fill, AutoSize = true,
+            Padding = new Padding(0, 20, 0, 0)
+        };
+
+        var btnOnly = new Button {
+            Text = "Only selected tables", AutoSize = true,
+            DialogResult = DialogResult.OK
+        };
+        btnOnly.Click += (s, e) => SelectedOption = ScopeOption.OnlySelected;
+
+        var btnAll = new Button {
+            Text = "All tables", AutoSize = true,
+            DialogResult = DialogResult.Retry
+        };
+        btnAll.Click += (s, e) => SelectedOption = ScopeOption.All;
+
+        var btnCancel = new Button {
+            Text = "Cancel", AutoSize = true,
+            DialogResult = DialogResult.Cancel
+        };
+        btnCancel.Click += (s, e) => SelectedOption = ScopeOption.Cancel;
+
+        panel.Controls.AddRange(new Control[] { btnOnly, btnAll, btnCancel });
+        layout.Controls.Add(panel);
+
+        AcceptButton = btnOnly;
+        CancelButton = btnCancel;
+    }
+}
+
+// -------------------------------------------------------------------
+// 2) SQL‐import dialog (schema now required)
+// -------------------------------------------------------------------
+public class SqlImportDialog : Form
+{
+    public TextBox SqlEndpoint { get; }
+    public TextBox DatabaseName { get; }
+    public TextBox Schema { get; }
+    private Button okButton;
+
+    public SqlImportDialog(string endpoint, string db, string schema)
+    {
+        Text = "Convert Direct Lake → Import";
+        AutoSize = true; AutoSizeMode = AutoSizeMode.GrowAndShrink;
+        StartPosition = FormStartPosition.CenterParent;
+        Padding = new Padding(20);
+
+        var layout = new TableLayoutPanel {
+            ColumnCount = 1, Dock = DockStyle.Fill,
+            AutoSize = true, AutoSizeMode = AutoSizeMode.GrowAndShrink
+        };
+        Controls.Add(layout);
+
+        // Endpoint
+        layout.Controls.Add(new Label { Text = "SQL Analytics Endpoint:", AutoSize = true });
+        SqlEndpoint = new TextBox { Width = 800, Text = endpoint };
+        layout.Controls.Add(SqlEndpoint);
+
+        // Database
+        layout.Controls.Add(new Label {
+            Text = "Lakehouse/Warehouse Name:", Padding = new Padding(0, 20, 0, 0),
+            AutoSize = true
+        });
+        DatabaseName = new TextBox { Width = 800, Text = db };
+        layout.Controls.Add(DatabaseName);
+
+        // Schema (required)
+        layout.Controls.Add(new Label {
+            Text = "Schema:", Padding = new Padding(0, 20, 0, 0),
+            AutoSize = true
+        });
+        Schema = new TextBox { Width = 800, Text = schema };
+        layout.Controls.Add(Schema);
+
+        // Buttons
+        var panel = new FlowLayoutPanel {
+            FlowDirection = FlowDirection.RightToLeft,
+            Dock = DockStyle.Fill, AutoSize = true,
+            Padding = new Padding(0, 20, 0, 0)
+        };
+        okButton = new Button {
+            Text = "OK", DialogResult = DialogResult.OK,
+            AutoSize = true, Enabled = false
+        };
+        var cancel = new Button {
+            Text = "Cancel", DialogResult = DialogResult.Cancel,
+            AutoSize = true
+        };
+        panel.Controls.AddRange(new Control[] { okButton, cancel });
+        layout.Controls.Add(panel);
+
+        AcceptButton = okButton;
+        CancelButton = cancel;
+
+        // Only enable OK when all three fields are non-empty
+        SqlEndpoint.TextChanged += Validate;
+        DatabaseName.TextChanged += Validate;
+        Schema.TextChanged += Validate;
+        Shown += (s,e) => Validate(s,e);
+    }
+
+    private void Validate(object sender, EventArgs e)
+    {
+        okButton.Enabled =
+            !string.IsNullOrWhiteSpace(SqlEndpoint.Text) &&
+            !string.IsNullOrWhiteSpace(DatabaseName.Text) &&
+            !string.IsNullOrWhiteSpace(Schema.Text);
+    }
+}
+
+// -------------------------------------------------------------------
+// 3) Main conversion logic
+// -------------------------------------------------------------------
+WaitFormVisible = false;
+Application.UseWaitCursor = false;
+
+// 3.1) Find all Direct Lake tables
+var allDirectLake = Model.Tables
+    .Where(t => t.Partitions.Count == 1
+             && t.Partitions[0].SourceType == PartitionSourceType.Entity
+             && t.Partitions[0].Mode == ModeType.DirectLake)
+    .ToList();
+
+// 3.2) And those you’ve selected
+var selectedDirect = Selected.Tables
+    .Cast<Table>()
+    .Where(t => t.Partitions.Count == 1
+             && t.Partitions[0].SourceType == PartitionSourceType.Entity
+             && t.Partitions[0].Mode == ModeType.DirectLake)
+    .ToList();
+
+// 3.3) Ask scope
+var scopeDialog = new ScopeSelectionDialog(selectedDirect.Count, allDirectLake.Count);
+var dr = scopeDialog.ShowDialog();
+if (dr == DialogResult.Cancel || scopeDialog.SelectedOption == ScopeSelectionDialog.ScopeOption.Cancel)
+    return;
+
+bool isAllTables = scopeDialog.SelectedOption == ScopeSelectionDialog.ScopeOption.All;
+var tablesToConvert = isAllTables
+    ? allDirectLake
+    : selectedDirect;
+
+if (tablesToConvert.Count == 0)
+{
+    Warning("No Direct Lake tables found in the chosen scope.");
+    return;
+}
+
+// 3.4) Ask for connection + schema
+var sqlDialog = new SqlImportDialog("", "", "");
+if (sqlDialog.ShowDialog() == DialogResult.Cancel) return;
+
+// 3.5) Upsert shared expression "SQLEndpoint"
+const string sqlTemplate = @"let
+    endpoint = Sql.Database(""{0}"",""{1}"")
+in
+    endpoint";
+var sqlexpr = Model.Expressions.FirstOrDefault(e => e.Name == "SQLEndpoint")
+           ?? Model.AddExpression("SQLEndpoint");
+sqlexpr.Expression = string.Format(
+    sqlTemplate,
+    sqlDialog.SqlEndpoint.Text,
+    sqlDialog.DatabaseName.Text);
+
+// 3.6) M‐partition template
+const string mTemplate = @"let
+    Source = SQLEndpoint,
+    Data = Source{{[Schema=""{0}"",Item=""{1}""]}}[Data]
+in
+    Data";
+
+// 3.7) Swap partitions
+foreach (var table in tablesToConvert)
+{
+    var oldP = table.Partitions[0];
+    oldP.Name += "_old";
+
+    var newP = table.AddMPartition(
+        oldP.Name.Replace("_old", ""),
+        string.Format(mTemplate, sqlDialog.Schema.Text, table.Name));
+    newP.Mode = ModeType.Import;
+
+    oldP.Delete();
+}
+
+// 3.8) If converting the **entire model**, delete the old DatabaseQuery expr
+if (isAllTables)
+{
+    var oldDbq = Model.Expressions.FirstOrDefault(e => e.Name == "DatabaseQuery");
+    if (oldDbq != null)
+        oldDbq.Delete();   // TE3 API: Expression.Delete() removes it from the model
+}
+
+// 3.9) Ensure default mode is Import
+Model.DefaultMode = ModeType.Import;
+
+Info("Conversion complete: Direct Lake → Import" + 
+     (isAllTables ? " (DatabaseQuery removed)" : "") + ".");
+```
+
+### Explanation
+
+The script first prompts the user to determine the scope of the conversion by choosing between converting only the selected tables or all tables in the model. It then identifies which tables are currently in Direct Lake mode within the chosen scope. If no applicable tables are found, or if the user cancels the dialog, the script terminates.
+
+The user is then prompted to enter the SQL Analytics Endpoint, the name of the Lakehouse or Warehouse, and a required Schema name. The script ensures all three fields are populated before allowing the user to proceed.
+
+Next, the script creates or updates a Shared Expression named `SQLEndpoint`, using the provided connection details. This expression uses the `Sql.Database` connector to access the Lakehouse or Warehouse.
+
+For each table being converted, the script creates a new Import mode M partition that references the `SQLEndpoint` expression and uses the specified schema and table name. The existing Direct Lake partition is renamed and then removed, leaving only the new Import partition.
+
+Finally, if the user chose to convert all Direct Lake tables in the model, the script checks for an existing Shared Expression named `DatabaseQuery` and deletes it if found. The model's default storage mode is then set to Import, and a confirmation message is displayed.
+
+## Use of AI disclaimer
+This script was created with the help of an LLM. 
diff --git a/content/common/toc.md b/content/common/toc.md
@@ -41,5 +41,6 @@
 #### @script-find-replace
 #### @script-convert-dlsql-to-dlol
 #### @script-convert-import-to-dlol
+#### @script-convert-dlol-to-import
 
 ## @script-helper-methods