No matter how advanced the data landscape becomes - from adding financials together in a spreadsheet to training AI models - the underlying principle is always the same. The most effective format to extract, transform, load and analyse data is the humble table.
A table organises data into columns and rows: the type of information being tracked in each column is called a field, and the combination of fields that form each row is called a record.
nintendo_games table| game_title | console_name | release_year | genre |
field
price
|
|---|---|---|---|---|
| Super Mario 64 | Nintendo 64 | 1996 | Platformer | £49.99 |
| Super Smash Bros. Melee | GameCube | 2001 | Fighting | £39.99 |
|
record
|
Nintendo DS | 2009 | RPG | £34.99 |
| Mario Kart 8 | Wii U | 2014 | Racing | £49.99 |
| The Legend of Zelda: Breath of the Wild | Nintendo Switch | 2017 | Action-Adventure | £59.99 |
Tables are often found in everyday files like PDFs or Excel spreadsheets, but larger organisations store them in Database Management Systems (DBMS). To interact with such systems, IBM engineers in the 1970s developed SEQUEL (Structured English Query Language) which was later shortened to SQL. As of this day, SQL remains the universal standard for querying structured data. Try writing your first SQL query below:
Select every field
In SQL, you select fields by listing them after the keyword SELECT. Let's start by selecting all five fields from the nintendo_games table above.