Fragen aus Vorstellungsgesprächen für chef de projet, von Bewerbern geteilt
Wie würden Sie eine Datenbank für ein 8-jähriges Kind beschreiben?
Think of it sort of like a shopping mall. There are stores (RDBMs), and there are stalls (NoSQL, loosely structured). Inside any store, there are sections (tables). In those sections there are shelves of stuff (columns). There's probably a computer in the store that knows exactly what shelf everything is on (indexes). Each shelf can have really anything on it (datatypes), but certain types of shelves are best for certain items; you wouldn't want to store marbles on a shelf that was just wide mesh. When you walk down the aisles, you'll see they are labeled (column names), so if you're looking for a specific type of say....pasta, you know to first start by looking in the aisle marked pasta.
Sorry, I missed a key element. Your shopping cart (query) would represent why you're looking at a store. You might be at a toy store looking for a specific gift (select * from toy_store where name is 'awesome popular toy of this week'), or you might be at a grocery store collecting ingredients for a recipe (join/subquery), so your basket might have all the various ingredients from your favorite peanut butter chocolate chip cookie recipe (select grocery_items.* from grocery_items LEFT JOIN recipe_items on grocery_items.item_name = recipe_items.ingredient where recipe_items.recipe_name = "Epic Cookies of weight gain")
Warum keine deutsche Antwort???