CREATE TABLE IF NOT EXISTS cards (
  id VARCHAR(36) NOT NULL,
  question TEXT NOT NULL,
  response TEXT NOT NULL,
  theme VARCHAR(50) NOT NULL,
  tags JSON,
  createdAt DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  updatedAt DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  INDEX idx_cards_theme (theme)
) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4 COLLATE = utf8mb4_unicode_ci;