DJ Dates

Database Literacy: Why use a database? (papercraft version)

Information is what we know about something.
Data is raw information that can be manipulated by a computer.
So a Database is a structured collection of information.

Files to print your own can be found here.

Our database might start out really simple, like this spreadsheet showing cars and their owners.
A field describes a single attribute of an object.
A record is a set of fields that describes a single person or object.
If our customer Sally gets married and changes her name, duplicate records may be created.
How do we know which Sally is the real Sally?
We can add a primary key field to uniquely identify Sally.
Unlike her last name, this identifier will never change.
However, we could still run into problems if Sally purchases a second car from us.
Duplicate data increases the potential for errors.
A relational database solves this problem by splitting different kinds of data into sets called tables.
One table is storing data about cars, while the other table is storing data about customers.
Keys are used to relate the data in the tables.
Primary keys uniquely identify records in a table…
… while Foreign keys identify records in a different table.
Databases use different types of relationships.
This relationship between cars and customers is called a One to Many relationship.
Sally can own many cars, but each car can only have one owner.
Notice how we have left over data that is not being duplicated?
This lack of duplication helps to ensure that the data is valid.
Luckily, the person using the database does not need to understand the structure of the database.
Instead, we can use a database form to allow us to only edit and see the data we are interested in, and hide all of the complexity, handling it behind the scenes.
So while a database does add more complexity….
These structures and rules help keep data valid,
And database forms hide the complexity, managing data for us behind the scenes.

This manipulative was created in Microsoft Excel. You can download this manipulative from my website and make your own copy. Once the appropriate sheets are printed on cardstock, the individual data elements should be cut out.

Pieces of self-adhesive loop and hook fastener “hooks” can be applied on the back of each data element. The spreadsheet and database sheets are printed on both sides of a piece of cardstock, with pieces of self-adhesive “fuzzies” applied to the spaces where data belongs.

Finally, the database form sheet is printed on normal paper, with the spaces removed showing the data fields accessible underneath the form.

Due to the fuzzy side of the hook and loop fastener adhesives being used twice as frequently as the hook sides, assembling two dozen of these manipulatives used more than 15 feet of Velcro and an overabundance of hook pieces were left over.

This tool and video is licensed for your free use under the Creative Commons Attribution – Non commercial – Share Alike license. This means that you may use and distribute the tool freely for non-commercial use, such as in your classroom, and you are welcome to make alterations to the tool, provided that you attribute me AND distribute your alterations under the same license.

If you find it useful, make any alterations, or have any questions or comments, I would love to hear from you, so please drop me a line...

why_use_a_database_papercraft_version.xlsx