CREATE TABLE ref_characteristic_types (characteristic_type_code CLOB, characteristic_type_description CLOB)
CREATE TABLE characteristics (characteristic_id NUMBER, characteristic_type_code CLOB, characteristic_data_type CLOB, characteristic_name CLOB, other_characteristic_details CLOB)
CREATE TABLE products (product_id NUMBER, color_code CLOB, product_category_code CLOB, product_name CLOB, typical_buying_price CLOB, typical_selling_price CLOB, product_description CLOB, other_product_details CLOB)
CREATE TABLE ref_colors (color_code CLOB, color_description CLOB)
CREATE TABLE ref_product_categories (product_category_code CLOB, product_category_description CLOB, unit_of_measure CLOB)
CREATE TABLE product_characteristics (product_id NUMBER, characteristic_id NUMBER, product_characteristic_value CLOB)

Find the product names that are colored 'white' but do not have unit of measurement 'Handful'.
SELECT t1.product_name FROM products AS t1 JOIN ref_product_categories AS t2 ON t1.product_category_code = t2.product_category_code JOIN ref_colors AS t3 ON t1.color_code = t3.color_code WHERE t3.color_description = "white" AND t2.unit_of_measure <> "Handful"
SELECT "t1"."product_name" FROM "products" "t1" JOIN "ref_product_categories" "t2" ON "Handful" <> "t2"."unit_of_measure" AND "t1"."product_category_code" = "t2"."product_category_code" JOIN "ref_colors" "t3" ON "t1"."color_code" = "t3"."color_code" AND "t3"."color_description" = "white"