An Excel table uses some of the same concepts as a database—namely, the idea of records and fields. However, databases and Excel worksheets are two very different entities.
For starters, databases, which programs like Microsoft Access and SQL Server let you create, have much stricter rules than Excel worksheets. Before you can add any data to a table in a database, you must carefully define the table.
You need to specify not only the name of each field but also the type of information the field can contain. Although Excel provides some of these so-called data validation features (Which you can read here), the program isn’t nearly as strict about it, validation is completely optional.
Also, unlike Excel, most modern databases are relational, which means they contain multiple tables that have specific links to one another. For example, a relational database might tie together customers in one table and the orders they’ve made in another.
In Excel, a worksheet can hold multiple tables of data, but there’s no way to tie them together. Most importantly, databases play a dramatically different role in the world of business. Typically, Excel is an end user program, which means ordinary mortals who generally know how to create an Excel file, design what it’s going to look like, and then fill it up with data to use it.
Ex-math majors, on the other hand, usually create databases, and they store information, behind-the-scenes, that non-programmer types end up using. For example, every time you use Google or search on Amazon for something to buy, you’re actually seeing answers that have been stored in, and generated by, massive and powerful databases.