Which ordinary value has a Russian value of унция?
CREATE TABLE "apothecaries_system" (
  "unit" text,
  "russian" text,
  "translation" text,
  "ratio" real,
  "metric_value" text,
  "avoirdupois_value" text,
  "ordinary_value" text
);
SELECT "ordinary_value" FROM "apothecaries_system" WHERE "russian"='унция';