-- Allow HTML in question text and explanation (for curated content with formulas, SVG, etc.)
ALTER TABLE questions ADD COLUMN allow_html INTEGER NOT NULL DEFAULT 0;

-- Mapping: exam9 variant number → test_id (so teachers can assign a variant as homework)
CREATE TABLE exam9_variant_tests (
  variant INTEGER PRIMARY KEY,
  test_id INTEGER NOT NULL REFERENCES tests(id) ON DELETE CASCADE
);