create Entity relationship of the database below postgresql draw it fully showing all connections and key the lecturer provided a model answer so please refer to it in the photoDiagram of Database Models Implemented but with using my database example below$-$ Create staff table $($insure all staff usernames are unique$)$

CREATE TABLE staff$($

staff$\_$id SERIAL PRIMARY KEY,

staff$\_$name VARCHAR$(255)$ UNIQUE NOT NULL,

staff$\_$pin INT NOT NULL,

staff$\_$type INT NOT NULL

$)$;

$--$ Create customer table

CREATE TABLE customer$($

customer$\_$id SERIAL PRIMARY KEY,

customer$\_$name VARCHAR$(255)$ NOT NULL,

customer$\_$allergies TEXT

$)$;

$--$ Create menu table

CREATE TABLE menu$($

dish$\_$id SERIAL PRIMARY KEY,

dish$\_$name VARCHAR$(255)$ NOT NULL,

dish$\_$calories INT NOT NULL,

dish$\_$price DECIMAL$(10,2)$ NOT NULL,

dish$\_$description VARCHAR$(1000)$

$)$;

CREATE TABLE allergens$($

allergen$\_$id SERIAL PRIMARY KEY,

allergen$\_$name VARCHAR$(255)$

$)$;

GRANT ALL ON allergens TO root;

INSERT INTO allergens $($allergen$\_$name$)$ VALUES $(\text{'}$Gluten$\text{'})$;

INSERT INTO allergens $($allergen$\_$name$)$ VALUES $(\text{'}$Dairy$\text{'})$;

INSERT INTO allergens $($allergen$\_$name$)$ VALUES $(\text{'}$Nuts$\text{'})$;

$--$create table relation for menu items and allergens

CREATE TABLE dish$\_$allergens $($

dish$\_$id INT,

allergen$\_$id INT,

FOREIGN KEY $($dish$\_$id$)$ REFERENCES menu$($dish$\_$id$)$ ON DELETE CASCADE,

FOREIGN KEY $($allergen$\_$id$)$ REFERENCES allergens$($allergen$\_$id$)$ ON DELETE CASCADE

$)$;

GRANT ALL ON orders TO root;

CREATE TABLE order$\_$details $($

order$\_$detail$\_$id SERIAL PRIMARY KEY,

order$\_$id INT REFERENCES orders$($order$\_$id$)$ ON DELETE CASCADE,

dish$\_$id INT REFERENCES menu$($dish$\_$id$)$ ON DELETE CASCADE,

quantity INT

$)$;

GRANT ALL ON order$\_$details TO root;

$--$ Create needs$\_$help table

CREATE TABLE needs$\_$help $($

help$\_$id SERIAL PRIMARY KEY,

customer$\_$id SERIAL REFERENCES customer$($customer$\_$id$)$ ON DELETE CASCADE,

resolved BOOLEAN DEFAULT FALSE

$)$;

GRANT ALL ON needs$\_$help TO root;

CREATE TABLE tables $($

table$\_$number SERIAL PRIMARY KEY,

customer$\_$id INT REFERENCES customer$($customer$\_$id$)$ ON DELETE CASCADE,

staff$\_$id INT REFERENCES staff$($staff$\_$id$)$ ON DELETE CASCADE

$)$;

GRANT ALL ON tables TO root;

CREATE TABLE payments $($

payment$\_$id SERIAL PRIMARY KEY,

payment$\_$time TIMESTAMP NOT NULL,

payment$\_$amount NUMERIC$(10,2)$ NOT NULL,

table$\_$number SERIAL REFERENCES tables$($table$\_$number$)$ ON DELETE CASCADE,

card$\_$holder VARCHAR$(255),$

card$\_$ending INT,

card$\_$expiry VARCHAR$(5)$

$)$;

GRANT ALL ON payments TO root; note that this questions was not answered before so please focus as the answer provided was incomplete. thank u