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• A spiral bound notebook – if you can get one with thick paper, like a visual diary, this activity will be easier
• Skewers
• A pair of scissors
• Pens

Make the database

Use the database

What’s happening?

This activity is all about doing lots of things at the same time. If you put one skewer through a hole in one recipe, it will fall off if you’ve cut that hole. If the hole isn’t cut, the recipe will stay on the skewer. When you stick a skewer through all the recipes, you’re doing the same thing, only with every recipe at the same time. If you use more than one skewer, then you’re checking several holes in every recipe at the same time. Each recipe will only fall if every skewered hole is cut.

If you only have a few recipes, this might seem like a very complicated way of sorting through them, and you might find it quicker just to look through all your recipes. However, if you have hundreds of recipes, it could take a long time to sort through all of them individually. This method can sort through all of them very quickly.

This system of cards with holes in them is over 60 years old. Commonly known as ‘Cope-Chat’ or ‘McBee Keysort’ cards, they were used for a wide range of applications, from medical studies to library catalogues. Users developed many impressive techniques to search for information. For example, a lot of cards would have two holes for each property – one where you cut it if it is true, and one where you cut if it is false. That way, you can search for a food that is liked by George, and disliked by Peter.

Applications

Card indexes like this have now been replaced with computer databases. These databases are actually quite similar to the card index you made in this activity. They contain a series of records, which are like the cards in this activity. The holes are called ‘fields’ and they are a bit more complicated than in the activity. Fields can be tick boxes or numbers or even words, and they can be searched. One of the main advantages of computer databases is that they can keep thousands or millions of records, and each can have as many searchable fields as you need.

Databases are a very good way to organise information, because you can find things using just a few quick questions. For example, internet search engines keep databases about what information is on websites. When you type something into a search engine, it looks up the database to find the best matches to your request. This way, they can search the entire internet, without having to ‘read’ every website every time someone does a search.