Henri

Hey again, I've been learning about relational database management systems, and I've come across a lot of talk about keys. What are keys in these systems?

Ah$,$ this is a little tricky. A key is sort of like a traditional password. The data in a system begins as an unorganized jumble of information. A key tells the system that an analyst can access all of the collected information so that it can be cleaned and organized.

Ah$,$ this is a little tricky. A key is simply a function that "unlocks" data in a table and allows an analyst to organize and use it$.$ For example, the function SUM is a key that unlocks a column of numerical data and organizes it for analysis.

Ah$,$ this is a little tricky. A key can be a column or collection of columns, depending on how it is