sample database to practice queries
Browse to https://irooc.github.io/sample-database and start quering. That page will load with the create-schema.sql file so you can start querying right away. This file is intenionally selfcontained but it loads the create-schema file from the same folder, as an alternative you could just execute the sql the first time. For the 'hacking' excersize the file contains a sql-injection like handling of the queries to show the basics of this. This is not intended to be a complete explanation.
Clone the repository to a local folder
git clone https://github.com/IRooc/sample-database.gitGo to https://sqliteonline.com and select File > Open DB from the menu and select the file sqlite_pizza_demo.db from the local folder.
Go to https://sqliteonline.com and paste in the contents from create-schema.sql and click RUN.
You now have a filled database where you can look around and start querying.
Example Query, (ingredient usage for all normal pizza's):
SELECT ingredients.Name, ingredients.portionsize * SUM(pizza_ingredients.portions) UsedAmount, COUNT(*) UsedCount
FROM pizza
JOIN pizza_ingredients on pizza.ID = pizza_ingredients.PizzaID
JOIN ingredients on ingredients.ID = pizza_ingredients.IngredientID
GROUP BY ingredients.Name, ingredients.portionsizeQuery getting the ingredients used in current orders:
SELECT IFNULL(ingredients2.Name, ingredients.Name), count(*)
FROM orders
JOIN order_lines on orders.ID = order_lines.orderid
LEFT JOIN order_custom_ingredients ON order_lines.ID = order_custom_ingredients.OrderLineID
LEFT JOIN ingredients ingredients2 on order_custom_ingredients.IngredientID = ingredients2.id
LEFT JOIN pizza on order_lines.pizzaid = pizza.id
LEFT JOIN pizza_ingredients ON pizza.id = pizza_ingredients.pizzaid
LEFT JOIN ingredients on pizza_ingredients.ingredientid = ingredients.id
GROUP BY IFNULL(ingredients2.name, ingredients.name)
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