apache/superset · error

Group by param is required

Error message

Group by param is required

What it means

TTestTable (Paired t-test chart) requires at least one Group By column to compute groups; the component throws when the groups array from form_data is missing or empty. Without a group dimension there is nothing to stratify the t-test by, so rendering aborts.

Solutions

1. Open the chart in Explore and set at least one Group By column, then save.
2. Fix imported chart JSON so formData.groupby is a non-empty array of valid columns.
3. When generating permalinks/URLs programmatically, do not send groupby: [].
4. Guard the chart container with an error boundary so one bad chart does not break the whole dashboard.

Example fix

// before
"groupby": [],

// after
"groupby": ["group"],

import { ensureIsArray } from '@superset-ui/core';

const hasGroupBy = Array.isArray(groups) && groups.length > 0;
if (!hasGroupBy) {
  // render configuration hint instead of mounting TTestTable
}

function hasGroupbyColumns(formData: unknown): formData is { groupby: string[] } {
  return (
    !!formData &&
    typeof formData === 'object' &&
    Array.isArray((formData as { groupby?: unknown }).groupby) &&
    ((formData as { groupby: unknown[] }).groupby.length as number) > 0
  );
}

<ErrorBoundary fallbackRender={() => <Alert type="error" message={t('Paired t-test requires a Group By column')} />}>
  <TTestTable ... />
</ErrorBoundary>

When it happens

Trigger: Opening a Paired t-test chart whose form_data has no groupby; a dashboard import where the groupby array was dropped; data-mask/URL params overwriting groupby with an empty list.

Common situations: Chart saved before Group By was configured; explore URL params (e.g. preselect_filters or permalink) clearing groupby; migrating charts between Superset versions with schema changes to groupby.

Related errors

• When using 'Group By' you are limited to use a single metric
• Chart is missing form_data
• Longitude and latitude columns are required
• Please call with an object. Example: `stringify myObj`
• Request is incorrect

AI-assisted analysis of apache/superset@f4587218dd (2026-08-14). Data as JSON: /api/errors/34c60f6a3b8ba40c. Report an issue: GitHub.

Appendix: source

Thrown at superset-frontend/plugins/plugin-chart-paired-t-test/src/TTestTable.tsx:271

      if (row === control) {
        return 'control';
      }

      // p-values significant below set threshold
      return Number(pValues[row]) <= alpha;
    },
    [control, pValues, alpha],
  );

  const handleRowClick = useCallback(
    (rowIndex: number) => {
      computeTTest(rowIndex);
    },
    [computeTTest],
  );

  if (!Array.isArray(groups) || groups.length === 0) {
    throw new Error('Group by param is required');
  }

  // Map a status keyword to its theme color; the control/significant/lift
  // states reuse the semantic antd tokens.
  const statusColor = (status: string): string | undefined => {
    switch (status) {
      case 'control':
        return theme.colorPrimary;
      case 'true':
        return theme.colorSuccess;
      case 'false':
        return theme.colorError;
      case 'invalid':
        return theme.colorWarning;
      default:
        return undefined;
    }
  };

View on GitHub (pinned to f4587218dd)