# Databases <!-- .element: class="r-fit-text" --> Week 11 --- ## Review  <!-- .element: style="height:400px" --> -- ### All Files Are Just What? Binary <!-- .element: class="fragment" --> -- ### How Many Bits in a Byte? 8 <!-- .element: class="fragment" --> -- ### How Many Bytes in a Gigabyte? 1,000,000,000 <!-- .element: class="fragment" --> -- ### What is a File Path? All folders plus a file name. <!-- .element: class="fragment" --> `C:\Users\Rylan\notes.txt` <!-- .element: class="fragment" --> --- ## Databases  <!-- .element: style="height:400px" --> -- ### What is a Database? > An organized collection of structured information <!-- .element: class="fragment" --> -- ### Why Not Use Files? - 🤔 Hard to organize <!-- .element: class="fragment" --> - 🐢 Too slow <!-- .element: class="fragment" --> - 💔 No relationships <!-- .element: class="fragment" --> -- ### Example Database  <!-- .element: style="height:400px" --> -- ### Databases vs. File Systems - Structured data model (usually relational) <!-- .element: class="fragment" --> - Database files not readable in a text editor <!-- .element: class="fragment" --> - Databases require a DBMS... <!-- .element: class="fragment" --> -- A database management system (DBMS) is a special program that allows you to interact with a database. -- ### How Do You Interact With Them? - Structured query language (SQL) - Used to modify data and _ask questions_ about it - SQL is a domain specific language (DSL) (not programming language) -- ### Where Are Databases Used? Everywhere! <!-- .element: class="fragment" --> NOTE: Every cloud app, every online account... they all use databases. -- ### Why Use a Database? Fast, reliable, structured. <!-- .element: class="fragment" --> -- ### Why Use a File System? User-friendly, no DBMS, better for BLOBs. <!-- .element: class="fragment" --> --- ## Review  <!-- .element: style="height:400px" --> -- ### What is a Database? An organized collection of structured information. <!-- .element: class="fragment" --> -- ### Benefits of a Database? Speed, relationships. <!-- .element: class="fragment" --> -- ### Benefits of a File System? User-friendly, no DBMS required, good for unstructured data. <!-- .element: class="fragment" --> -- ### Does Google Store User Data in Regular Files? No\*, it uses databases. <!-- .element: class="fragment" --> \*But databases use regular files... so kinda. <!-- .element: class="fragment" --> --- ## Now for Some Coding... <!-- .element: class="r-fit-text" --> [Python: Dictionaries](/2024/fall/computer-science/slides/python-dictionaries)