CREATE TABLE ref_product_categories (unit_of_measure VARCHAR, product_category_code VARCHAR)
CREATE TABLE products (product_category_code VARCHAR, product_name VARCHAR)

What is the unit of measurement of product named 'cumin'?
SELECT t2.unit_of_measure FROM products AS t1 JOIN ref_product_categories AS t2 ON t1.product_category_code = t2.product_category_code WHERE t1.product_name = "cumin"
SELECT "t2"."unit_of_measure" FROM "products" AS "t1" JOIN "ref_product_categories" AS "t2" ON "t1"."product_category_code" = "t2"."product_category_code" WHERE "cumin" = "t1"."product_name"