w3resource logo


SQL WHERE CLAUSE PRIMAY AND FOREIGN KEY

SQL join two tables related by a single column primary key or foreign key pair using where clause

Secondary Nav

Description

In this page we are going to discuss the usage of two or more tables in a joining with single column PRIMARY KEY and FOREIGN KEY.

Example

Sample table : foods

Sample table : company

To get 'item_name' and 'item_unit' from 'foods' table and 'company_name' and 'company_city' form 'company' table after a joining with following conditions-

1. 'company_id' is primary key in 'company' table,

2. 'company_id' is foreign key in 'foods' table which is referencing to the, primary key of 'company' table,

3. 'company_id' of 'company' and 'foods' must be same,

4. 'company_city' of 'company' column must be 'London',

the following sql statement can be used :

SELECT foods.item_name,foods.item_unit,
company.company_name, company.company_city
FROM foods ,company
WHERE  foods.company_id =company.company_id
AND company.company_city='London';

Output

ITEM_NAME                 ITEM_UNIT  COMPANY_NAME              COMPANY_CITY
------------------------- ---------- ------------------------- -------------
Cheez-It                  Pcs        Jack Hill Ltd             London
BN Biscuit                Pcs        Jack Hill Ltd             London
Mighty Munch              Pcs        Foodies.                  London
Pot Rice                  Pcs        Jack Hill Ltd             London

See our Model Database

Here is a new document which is a collection of questions with short and simple answers, useful for learning SQL as well as for interviews.



Is this content useful for you?

 


You might be using Adblocker. Since w3resource does not charge anything from users, all of our expenses (e.g. Hosting, Content Creation, Development etc.) are met by advertisement. Please whitelist w3resource.