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Relational Database dimensions (FileMaker)

TEXT/DOCUMENTS
E.g. Microsoft Word
One dimensionsal - just a list. You can create tables, but that is like creating multiple columns - it is still a list, just broken into columns for convenience.

SPREADSHEETS
E.g. Microsoft Excel
Two dimensional - rows and columns. In some sense Excel recognizes that a column belongs together and a row belongs together. For example, a row may be a name and a set of grades for that person. The first column would then be the names of students in a class, the second column their scores on Quiz 1, etc.

RELATIONAL DATABASES
E.g. Microsoft Access, FileMaker
Concept 1: Three dimensional - rows, columns and pillars. (Picture to come.) Take the Excel example and go to the last column - final score. Then add a pillar coming out of each cell, representing the final grade. This pillar can take values from A to F, and slides up or down until the appropriate grade is in the underlying Excel spreadsheet.

Concept 2: Databases have spreadsheets as their underlying data. Think of that as not a flat piece of paper but as a bunch of boxes without tops, all lined up in rows and columns. The database allows you to create different views of that spreadsheet. Imagine a big piece of cardboard that covers all of the boxes. You can cut windows in it so when you set it on the boxes you only see what you choose to see.