diff --git a/packages/iris-grid/src/ColumnStatistics.tsx b/packages/iris-grid/src/ColumnStatistics.tsx
index 344915fde6..15c7219144 100644
--- a/packages/iris-grid/src/ColumnStatistics.tsx
+++ b/packages/iris-grid/src/ColumnStatistics.tsx
@@ -30,7 +30,7 @@ interface ColumnStatisticsProps {
 interface ColumnStatisticsState {
   error: unknown;
   loading: boolean;
-  statistics: Statistic[] | null;
+  statistics: readonly Statistic[] | null;
   numRows: number;
 }
 
@@ -81,7 +81,7 @@ class ColumnStatistics extends Component<
   cancelablePromise: CancelablePromise<APIColumnStatistics> | null;
 
   maybeGenerateStatistics(): void {
-    const { model } = this.props;
+    const { column, model } = this.props;
 
     const numRows =
       model.rowCount -
@@ -89,7 +89,7 @@ class ColumnStatistics extends Component<
       model.floatingBottomRowCount -
       model.floatingTopRowCount;
     this.setState({ numRows });
-    if (!model.isColumnStatisticsAvailable) {
+    if (!model.isColumnStatisticsAvailable || column.isProxy === true) {
       this.setState({ loading: false });
     } else if (numRows < ColumnStatistics.AUTO_GENERATE_LIMIT) {
       this.handleGenerateStatistics();
diff --git a/packages/iris-grid/src/CrossColumnSearch.tsx b/packages/iris-grid/src/CrossColumnSearch.tsx
index 0243562b60..0d446f3182 100644
--- a/packages/iris-grid/src/CrossColumnSearch.tsx
+++ b/packages/iris-grid/src/CrossColumnSearch.tsx
@@ -17,6 +17,7 @@ import type {
 import { TableUtils } from '@deephaven/jsapi-utils';
 import './CrossColumnSearch.scss';
 import { ColumnName } from './CommonTypes';
+import { DisplayColumn } from './IrisGridModel';
 
 interface CrossColumnSearchProps {
   value: string;
@@ -27,7 +28,7 @@ interface CrossColumnSearchProps {
     selectedColumns: readonly ColumnName[],
     invertSelection: boolean
   ) => void;
-  columns: readonly Column[];
+  columns: readonly DisplayColumn[];
 }
 
 interface CrossColumnSearchState {
@@ -233,23 +234,27 @@ class CrossColumnSearch extends PureComponent<
             <div className="cross-column-popup">
               Searched Columns
               <div className="cross-column-scroll">
-                {columns.map(column => (
-                  <React.Fragment key={column.name}>
-                    <Checkbox
-                      className="cross-column-checkbox"
-                      checked={
-                        invertSelection
-                          ? !selectedColumns.includes(column.name)
-                          : selectedColumns.includes(column.name)
-                      }
-                      onChange={() => this.toggleColumn(column.name)}
-                    >
-                      {column.name}
-                    </Checkbox>
+                {columns.map(column => {
+                  if (column.isProxy === true) return null;
 
-                    {column.type.substring(column.type.lastIndexOf('.') + 1)}
-                  </React.Fragment>
-                ))}
+                  return (
+                    <React.Fragment key={column.name}>
+                      <Checkbox
+                        className="cross-column-checkbox"
+                        checked={
+                          invertSelection
+                            ? !selectedColumns.includes(column.name)
+                            : selectedColumns.includes(column.name)
+                        }
+                        onChange={() => this.toggleColumn(column.name)}
+                      >
+                        {column.name}
+                      </Checkbox>
+
+                      {column.type.substring(column.type.lastIndexOf('.') + 1)}
+                    </React.Fragment>
+                  );
+                })}
               </div>
               <div className="cross-column-button-bar">
                 <button
diff --git a/packages/iris-grid/src/IrisGridModel.ts b/packages/iris-grid/src/IrisGridModel.ts
index ad9b64f4ab..ef47b703bd 100644
--- a/packages/iris-grid/src/IrisGridModel.ts
+++ b/packages/iris-grid/src/IrisGridModel.ts
@@ -42,6 +42,12 @@ export type DisplayColumn = Column & {
    * whereas `displayName` can be any string and does not need to be unique.
    */
   displayName?: string;
+
+  /**
+   * Whether this column is a proxy column for other columns or not.
+   * If it's a proxy column, it may not appear in some lists.
+   */
+  isProxy?: boolean;
 };
 
 type IrisGridModelEventNames =
diff --git a/packages/iris-grid/src/IrisGridTableModelTemplate.ts b/packages/iris-grid/src/IrisGridTableModelTemplate.ts
index 4516615a2f..3f31aa344d 100644
--- a/packages/iris-grid/src/IrisGridTableModelTemplate.ts
+++ b/packages/iris-grid/src/IrisGridTableModelTemplate.ts
@@ -382,7 +382,8 @@ class IrisGridTableModelTemplate<
 
   get rowCount(): number {
     return (
-      this.table.size +
+      // Table size can be negative if the table isn't ready yet
+      Math.max(this.table.size, 0) +
       this.pendingNewRowCount +
       (this.totals?.operationOrder?.length ?? 0)
     );
diff --git a/packages/iris-grid/src/IrisGridTreeTableModel.ts b/packages/iris-grid/src/IrisGridTreeTableModel.ts
index 73192723fc..f26218c4dc 100644
--- a/packages/iris-grid/src/IrisGridTreeTableModel.ts
+++ b/packages/iris-grid/src/IrisGridTreeTableModel.ts
@@ -49,6 +49,7 @@ class IrisGridTreeTableModel extends IrisGridTableModelTemplate<
         constituentType: TableUtils.dataType.STRING,
         isPartitionColumn: false,
         isSortable: false,
+        isProxy: true,
         description: 'Key column',
         filter: () => {
           throw new Error('Filter not implemented for virtual column');
@@ -112,13 +113,11 @@ class IrisGridTreeTableModel extends IrisGridTableModelTemplate<
     if (hasChildren) {
       for (let i = 0; i < this.virtualColumns.length; i += 1) {
         const key = i + (depth - 1) + (this.virtualColumns.length - 1);
-        if (!modifiedData.has(key)) {
+        const cellData = modifiedData.get(key);
+        if (cellData == null) {
           log.warn('Missing key data for virtual column', i, depth, key, row);
         } else {
-          const cellData = modifiedData.get(key);
-          if (cellData != null) {
-            modifiedData.set(i, cellData);
-          }
+          modifiedData.set(i, cellData);
         }
       }
     }
diff --git a/packages/iris-grid/src/sidebar/aggregations/AggregationEdit.tsx b/packages/iris-grid/src/sidebar/aggregations/AggregationEdit.tsx
index 4e7e33ab47..4ff780149b 100644
--- a/packages/iris-grid/src/sidebar/aggregations/AggregationEdit.tsx
+++ b/packages/iris-grid/src/sidebar/aggregations/AggregationEdit.tsx
@@ -3,11 +3,11 @@ import classNames from 'classnames';
 import { CSSTransition } from 'react-transition-group';
 import { Button, Checkbox, ItemList, ThemeExport } from '@deephaven/components';
 import { dhSortAlphaDown, dhSortAlphaUp } from '@deephaven/icons';
-import type { Column } from '@deephaven/jsapi-types';
 import { TableUtils } from '@deephaven/jsapi-utils';
 import { Aggregation } from './Aggregations';
 import { filterValidColumns } from './AggregationUtils';
 import './AggregationEdit.scss';
+import { DisplayColumn } from '../../IrisGridModel';
 
 interface AggregationEditItem {
   value: string;
@@ -16,7 +16,7 @@ interface AggregationEditItem {
 
 export type AggregationEditProps = {
   aggregation: Aggregation;
-  columns: readonly Column[];
+  columns: readonly DisplayColumn[];
   onChange: (aggregation: Aggregation) => void;
 };
 
diff --git a/packages/iris-grid/src/sidebar/aggregations/AggregationUtils.ts b/packages/iris-grid/src/sidebar/aggregations/AggregationUtils.ts
index db03167e9e..9233ab906b 100644
--- a/packages/iris-grid/src/sidebar/aggregations/AggregationUtils.ts
+++ b/packages/iris-grid/src/sidebar/aggregations/AggregationUtils.ts
@@ -1,5 +1,5 @@
-import type { Column } from '@deephaven/jsapi-types';
 import { TableUtils } from '@deephaven/jsapi-utils';
+import { DisplayColumn } from '../../IrisGridModel';
 import AggregationOperation from './AggregationOperation';
 
 export const SELECTABLE_OPTIONS = [
@@ -68,12 +68,15 @@ export const isValidOperation = (
 };
 
 export const filterValidColumns = (
-  columns: readonly Column[],
+  columns: readonly DisplayColumn[],
   operationType: AggregationOperation
-): Column[] => columns.filter(c => isValidOperation(operationType, c.type));
+): DisplayColumn[] =>
+  columns.filter(
+    c => c.isProxy !== true && isValidOperation(operationType, c.type)
+  );
 
 export const getOperationColumnNames = (
-  columns: readonly Column[],
+  columns: readonly DisplayColumn[],
   operationType: AggregationOperation,
   selected: readonly string[],
   invert: boolean
diff --git a/packages/iris-grid/src/sidebar/visibility-ordering-builder/VisibilityOrderingBuilder.tsx b/packages/iris-grid/src/sidebar/visibility-ordering-builder/VisibilityOrderingBuilder.tsx
index 7b8686e3a9..9bc4955f01 100644
--- a/packages/iris-grid/src/sidebar/visibility-ordering-builder/VisibilityOrderingBuilder.tsx
+++ b/packages/iris-grid/src/sidebar/visibility-ordering-builder/VisibilityOrderingBuilder.tsx
@@ -29,7 +29,7 @@ import { Button, SearchInput } from '@deephaven/components';
 import clamp from 'lodash.clamp';
 import throttle from 'lodash.throttle';
 import './VisibilityOrderingBuilder.scss';
-import IrisGridModel from '../../IrisGridModel';
+import IrisGridModel, { DisplayColumn } from '../../IrisGridModel';
 import { ColumnName } from '../../CommonTypes';
 import ColumnHeaderGroup from '../../ColumnHeaderGroup';
 import VisibilityOrderingItem from './VisibilityOrderingItem';
@@ -92,6 +92,11 @@ class VisibilityOrderingBuilder extends PureComponent<
     DOWN: 'DOWN',
   } as const;
 
+  static shouldRenderColumn(column: DisplayColumn): boolean {
+    // We don't want to render the proxy column in the visibility ordering list
+    return column.isProxy !== true;
+  }
+
   constructor(props: VisibilityOrderingBuilderProps) {
     super(props);
 
@@ -1081,7 +1086,10 @@ class VisibilityOrderingBuilder extends PureComponent<
   }
 
   makeVisibilityOrderingList = memoize(
-    (columns: readonly Column[], treeItems: readonly IrisGridTreeItem[]) => {
+    (
+      columns: readonly DisplayColumn[],
+      treeItems: readonly IrisGridTreeItem[]
+    ) => {
       const { movedColumns } = this.props;
 
       const elements = [];
@@ -1117,7 +1125,9 @@ class VisibilityOrderingBuilder extends PureComponent<
             movedColumns
           );
           const column = columns[modelIndex];
-          elements.push(this.renderImmovableItem(column.name));
+          if (VisibilityOrderingBuilder.shouldRenderColumn(column)) {
+            elements.push(this.renderImmovableItem(column.name));
+          }
         }
 
         return elements;
@@ -1131,7 +1141,9 @@ class VisibilityOrderingBuilder extends PureComponent<
       ) {
         const modelIndex = GridUtils.getModelIndex(visibleIndex, movedColumns);
         const column = columns[modelIndex];
-        elements.push(this.renderImmovableItem(column.name));
+        if (VisibilityOrderingBuilder.shouldRenderColumn(column)) {
+          elements.push(this.renderImmovableItem(column.name));
+        }
       }
 
       if (firstMovableIndex !== null && firstMovableIndex > 0) {
@@ -1159,7 +1171,9 @@ class VisibilityOrderingBuilder extends PureComponent<
       ) {
         const modelIndex = GridUtils.getModelIndex(visibleIndex, movedColumns);
         const column = columns[modelIndex];
-        elements.push(this.renderImmovableItem(column.name));
+        if (VisibilityOrderingBuilder.shouldRenderColumn(column)) {
+          elements.push(this.renderImmovableItem(column.name));
+        }
       }
 
       return elements;