--- categories: - Databases - Programming Languages tags: [SQL] --- # SQL: Demonstration database For the purposes of demonstration we will work from a made-up database. The examples are created using SQLite but they are transferable to any SQL database. This database stores information about computers, their manufacturers, properties and sale data: - The overall database is `computer_sales` - It contains the following [tables](/Databases/Relational_database_architecture.md#table): `manufacturer`, `model`, `sales` - Example [fields](/Databases/Relational_database_architecture.md#field) that belong to these tables: `manufacturer_id` , `model_id` , `name`, `year_founded` , `ram` , `sale_date` Below are the `model` and `manufacturer` tables output from the SQLite terminal client. The model table: ``` model_id manufacturer_id name cpu_speed ram cores wifi release_date ---------- --------------- ---------------------- ---------- ---------- ---------- ---------- ------------ 1 1 Raspberry Pi 1 Model A 0.7 256.0 1 0 2013-02-01 2 1 Raspberry Pi 1 Model B 0.7 256.0 1 0 2012-04-01 3 1 Raspberry Pi 1 Model B 0.7 512.0 1 0 2012-10-01 4 1 Raspberry Pi 1 Model A 0.7 512.0 1 0 2014-11-01 5 1 Raspberry Pi 1 Model B 0.7 512.0 1 0 2014-07-01 6 1 Raspberry Pi 2 Model B 0.9 1024.0 4 0 2015-02-01 7 1 Raspberry Pi 3 Model B 1.2 1024.0 4 1 2016-02-01 8 1 Raspberry Pi 3 Model B 1.4 1024.0 4 1 2018-03-14 9 1 Raspberry Pi 3 Model A 1.4 1024.0 4 1 2018-11-01 10 1 Raspberry Pi 4 Model B 1.5 1024.0 4 1 2019-06-24 11 1 Raspberry Pi 4 Model B 1.5 2048.0 4 1 2019-06-24 12 1 Raspberry Pi 4 Model B 1.5 4096.0 4 1 2019-06-24 13 1 Raspberry Pi Zero 1.0 512.0 1 0 2015-11-01 14 1 Raspberry Pi Zero W 1.0 512.0 1 1 2017-02-28 15 2 Apple Lisa 0.008 1.0 1 0 1983-01-19 16 2 Apple iMac 3.7 8192.0 4 1 2019-03-19 17 2 Apple MacBook Pro 2.6 16384.0 6 1 2019-05-21 18 2 Apple MacBook Air 2.6 8192.0 2 1 2019-07-09 19 3 Commodore VIC-20 0.00102 0.005 1 0 1980-01-01 20 3 Commodore 64 0.001023 0.064 1 0 1982-08-01 21 3 Amiga 500 0.00716 0.5 1 0 1987-04-01 ``` The manufacturer table: ``` manufacturer_id name url year_founded trading --------------- ------------ ----------------------- ------------ ---------- 1 Raspberry Pi 2008 1 2 Apple 1976 1 3 Commodore 1954 0 ```