Order management SQL schema - sql

Question

I am designing a SQL database for sales person of a firm, where each customer will order multiple items from the firm. I want to store this order uniquely to the customer. Which will be linked to customer table.
Customer Table :
Cust_id
Cust_name
Cust_phone
Currently I am thinking of making a separate order table for each order
Order Table:
Product_id
Prod_quantity
Total_amt
but can't figure out how to link it back to customer. Or how to uniquely identify each order table.
I would have done it in NoSQL but data has to be locally stored in SQLite.
Customer may order multiple times so I should be able to identify current and previous orders

Answer 1

Do not create a separate table for each order! That's a very bad design. Relational tables aren't spreadsheets!
Have one table for the orders with a foreign key pointing to the customers. For the items of orders have a linking table with a foreign key to the order and another to the item. That's fairly standard thing (I'm pretty certain you'll find such a classic example in many tutorials about relational database design.). Something along the lines of:
CREATE TABLE customer
(id integer,
name varchar(64),
...
PRIMARY KEY (id));
CREATE TABLE product
(id integer,
name varchar(64),
...
PRIMARY KEY (id));
CREATE TABLE order
(id integer,
customer integer,
...
PRIMARY KEY (id),
FOREIGN KEY (customer)
REFERENCES customer
(id));
CREATE TABLE order_product
(order integer,
product integer,
amount integer,
...
PRIMARY KEY (order,
product),
FOREIGN KEY (order)
REFERENCES order
(id),
FOREIGN KEY (customer)
REFERENCES customer
(id));
(order might be a bad choice for a table or column name in some DBMS as it's also a keyword and thus required quoting. So probably chose something else. I used it just for the sake of clarity.)