Utilize the JigSaw SQL file below to create a Star Schema diagram. Remember, to create a Star Schema from a normalized data model, you will need to denormalize the data model into fact and dimension tables.

The diagram should contain all of the facts and dimension tables necessary to integrate the JigSaw operational database into a data warehouse. Write a brief paper describing the challenges you experienced in completing this assignment.

-- CREATE DATABASE js;

CREATE TABLE buy_methods ( buy_code CHAR(4) NOT NULL, buy_desc CHAR(25) NOT NULL, PRIMARY KEY (buy_code) );

-- ALTER TABLE buy_methods COMMENT 'store, internet, TE.';

CREATE TABLE payment_methods ( pay_code CHAR(4) NOT NULL, pay_desc CHAR(25) NOT NULL, PRIMARY KEY (pay_code) );

-- ALTER TABLE payment_methods COMMENT 'method of payment: cash, credit card, check.';

CREATE TABLE countries ( cou_id smallint NOT NULL, country_name CHAR(30) NOT NULL, PRIMARY KEY (cou_id) );

-- ALTER TABLE countries COMMENT '';

CREATE TABLE cities ( city_id integer NOT NULL, city_name CHAR(30) NOT NULL, cou_id smallint NOT NULL, PRIMARY KEY (city_id) );

-- ALTER TABLE cities COMMENT '';

CREATE TABLE customers ( cus_id integer NOT NULL, cus_name CHAR(30) NOT NULL, cus_lastname CHAR(30) NOT NULL, add_street CHAR(50), add_zipcode CHAR(10), city_id integer NOT NULL, PRIMARY KEY (cus_id) );

-- ALTER TABLE customers COMMENT '';

CREATE TABLE invoices ( invoice_number integer NOT NULL, buy_code CHAR(4) NOT NULL, inv_date DATE NOT NULL, pay_code CHAR(4) NOT NULL, inv_price NUMERIC(8,2) DEFAULT 0 NOT NULL, cus_id integer NOT NULL, PRIMARY KEY (invoice_number) );

-- ALTER TABLE invoices COMMENT '';

CREATE TABLE manufacturers ( man_code CHAR(3) NOT NULL, man_desc CHAR(25) NOT NULL, PRIMARY KEY (man_code) );

-- ALTER TABLE manufacturers COMMENT 'Puzzle Manufacturers';

CREATE TABLE products ( pro_code CHAR(8) NOT NULL, man_code CHAR(3) NOT NULL, pro_name CHAR(35) NOT NULL, pro_description CHAR(100), pro_type CHAR(10) DEFAULT 'PUZZLE' NOT NULL, pro_theme CHAR(50), pro_pieces integer, pro_packaging CHAR(20), pro_shape CHAR(20), pro_style CHAR(20), pro_buy_price NUMERIC(6,2) DEFAULT 0 NOT NULL, pro_sel_price NUMERIC(6,2) DEFAULT 0 NOT NULL, pro_stock integer DEFAULT 0 NOT NULL, pro_stock_min integer DEFAULT 0 NOT NULL, pro_stock_max integer DEFAULT 0 NOT NULL, PRIMARY KEY (pro_code, man_code) );

-- ALTER TABLE products COMMENT 'Products (Puzzles & Accesories)';

CREATE TABLE invoices_detail ( invoice_number integer NOT NULL, linenr smallint NOT NULL, pro_code CHAR(8) NOT NULL, man_code CHAR(3) NOT NULL, cant_prod smallint NOT NULL, price_unit NUMERIC(6,2) NOT NULL, price NUMERIC(8,2) NOT NULL, PRIMARY KEY (invoice_number, linenr) );

-- ALTER TABLE invoices_detail COMMENT '';

ALTER TABLE invoices ADD CONSTRAINT buy_place_invoices_fk FOREIGN KEY (buy_code) REFERENCES buy_methods (buy_code) ON DELETE NO ACTION ON UPDATE NO ACTION;

ALTER TABLE invoices ADD CONSTRAINT payment_methods_invoices_fk FOREIGN KEY (pay_code) REFERENCES payment_methods (pay_code) ON DELETE NO ACTION ON UPDATE NO ACTION;

ALTER TABLE cities ADD CONSTRAINT countries_cities_fk FOREIGN KEY (cou_id) REFERENCES countries (cou_id) ON DELETE NO ACTION ON UPDATE NO ACTION;

ALTER TABLE customers ADD CONSTRAINT cities_clients_fk FOREIGN KEY (city_id) REFERENCES cities (city_id) ON DELETE NO ACTION ON UPDATE NO ACTION;

ALTER TABLE invoices ADD CONSTRAINT clients_invoices_fk FOREIGN KEY (cus_id) REFERENCES customers (cus_id) ON DELETE NO ACTION ON UPDATE NO ACTION;

ALTER TABLE invoices_detail ADD CONSTRAINT invoices_invoices_detail_fk FOREIGN KEY (invoice_number) REFERENCES invoices (invoice_number) ON DELETE NO ACTION ON UPDATE NO ACTION;

ALTER TABLE products ADD CONSTRAINT manufacturers_products_fk FOREIGN KEY (man_code) REFERENCES manufacturers (man_code) ON DELETE NO ACTION ON UPDATE NO ACTION;

ALTER TABLE invoices_detail ADD CONSTRAINT products_invoices_detail_fk FOREIGN KEY (pro_code, man_code) REFERENCES products (pro_code, man_code) ON DELETE NO ACTION ON UPDATE NO ACTION;