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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
<title>Ladies Learning Code</title>
<link rel="stylesheet" href="framework/css/inspire.css" data-noprefix>
<link rel="stylesheet" href="framework/css/fonts.css" data-noprefix>
<link rel="stylesheet" href="framework/css/highlightjs/github.css" data-noprefix>
<link rel="stylesheet" href="framework/css/styles.css" data-noprefix>
<link rel="stylesheet" href="framework/css/a11y/plugin.css" data-noprefix>
<link rel="shortcut icon" href="framework/img/favicon.ico">
<!-- Takes care of CSS3 prefixes -->
<script src="framework/scripts/prefixfree.min.js"></script>
<!-- opens all links in a new window -->
<base target="_blank">
</head>
<body class="en">
<section>
<article class="slide welcome highlight">
<h1><img class="logo-stacked" src="framework/img/llc-logo-stacked-white.png" alt="Ladies Learning Code logo">Welcome!</h1>
<div class="instructions">
<h2>Open,<br>Download <br>or Install</h2>
<ol class="downloads">
<!--<li>Learner files (zip file): <a href="https://github.com/ladieslearningcode/llc-sql/archive/master.zip">http://bit.ly/clc-sql</a>
<ul>
<li>unzip the learner file (<em>extract all</em> if you’re on a PC)</li>
<li>open <em>slides_abridged.html</em> in the browser to view the slides</li>
</ul>
</li>-->
<li>Slides: <a href="https://ladieslearningcode.github.io/llc-sql/slides_abridged.html">https://ladieslearningcode.github.io/llc-sql/slides_abridged.html</a></li>
<li>Data file: <a href="https://bit.ly/cnf_db">https://bit.ly/cnf_db</a></li>
<li>SQLite Browser: <a href="https://sqliteonline.com/">https://sqliteonline.com/</a></li>
</ol>
<h2>New to Zoom?</h2>
<ul class="downloads">
<li><a href="https://bit.ly/en-zoom-main">https://bit.ly/en-zoom-main</a></li>
</ul>
</div>
<footer>
<a class="left" rel="license" href="http://creativecommons.org/licenses/by-nc/4.0/"><img alt="Creative Commons License" src="framework/img/cc-by-nc.png" /></a>
<p class="left">Content created by <a href="https://ca.linkedin.com/in/matt-baum">Matthew Baum</a> for <a prefix="cc: http://creativecommons.org/ns#" href="http://ladieslearningcode.com" property="cc:attributionName" rel="cc:attributionURL">Ladies Learning Code</a></p>
<p class="right">Use the left <span class="arrow">←</span> and right <span class="arrow">→</span> arrow keys to navigate</p>
</footer>
</article>
<article class="slide intro">
<img class="logo" src="framework/img/llc-logo-white.png" alt="Ladies Learning Code logo">
<h1 class="heading-bg">
<span>Managing Data with SQL</span>
</h1>
<ul>
<li><a href="http://twitter.com/learningcode">@learningcode</a></li>
<li><a href="https://twitter.com/search?q=%23ladieslearningcode&src=typd">#ladieslearningcode</a></li>
</ul>
<!-- INSTRUCTOR DETAILS -->
<!--<img class="instructor" src="http://placehold.it/225x225" alt="Instructor Name">
<h2><span class="cursive">with</span> Instructor name</h2>
<ul>
<li><a href="mailto:">hello@email.com</a></li>
<li><a href="http://website.com">website.com</a></li>
<li><a href="http://twitter.com/">@twitter</a></li>
</ul>-->
<!--<div class="sponsor">
<p>In partnership with<br> <img src="framework/img/google-org-logo.svg" alt="Google.org"></p>
</div>-->
<footer>
<a class="left" rel="license" href="http://creativecommons.org/licenses/by-nc/4.0/"><img alt="Creative Commons License" src="framework/img/cc-by-nc.png" /></a>
<p class="left">Content created by <a href="https://ca.linkedin.com/in/matt-baum">Matthew Baum</a> for <a prefix="cc: http://creativecommons.org/ns#" href="http://ladieslearningcode.com" property="cc:attributionName" rel="cc:attributionURL">Ladies Learning Code</a></p>
<p class="right">Use the left <span class="arrow">←</span> and right <span class="arrow">→</span> arrow keys to navigate</p>
</footer>
</article>
</section>
<header class="slide title" data-toc>
<h2>Introductions</h2>
</header>
<section>
<article class="slide" data-markdown>
<script type="text/template">
#Today's Project
Data is ever present in our lives and, as we'll see today, SQL is a powerful language that allows us to extract useful insights from large quantities of information.
We'll be working with real data from the Canadian government, called the [Canadian Nutrient File (CNF)](https://www.canada.ca/en/health-canada/services/food-nutrition/healthy-eating/nutrient-data.html)!
This database contains nutritional information on over 5000 foods published by Health Canada.
We'll start with SQL basics and then explore the data through some fun challenges.
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#How might you use SQL?
SQL is used in the databases serving many business roles, including:
* Customer Support
* Marketing
* Sales
* Finance
* Have you heard about Business Intelligence (BI)?
> What do **you** think? What motivated you to join us today?
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#What we'll cover today
1. What are data, databases and SQL?
1. Searching for text and keywords
1. Finding the data we want
1. Ordering data logically
1. Grouping data into categories
1. Calculating simple statistics
1. Joining together related data
</script>
</article>
<section class="slide" data-markdown>
<script type="text/template">
# Getting started with Zoom
</script>
</section>
<section class="slide" data-markdown>
<script type="text/template">
# Getting started with Zoom
</script>
</section>
<section class="slide" data-markdown>
<script type="text/template">
# Getting started with Zoom
</script>
</section>
<section class="slide" data-markdown>
<script type="text/template">
# Getting started with Zoom
</script>
</section>
<article class="slide" data-markdown>
<script type="text/template">
# Coders' code
1. Be friendly and welcoming
1. Be respectful of others by choosing words and actions with care
1. Be mindful of how much space you take up in conversations
1. Ask questions
1. Take care of your body
1. No photos or audio/video recordings
</script>
</article>
<section class="slide title" data-markdown>
<script type="text/template">
#Land acknowledgement
</script>
</section>
<article class="slide" data-markdown>
<script type="text/template">
#Getting Set Up
1. Open SQLite in your web browser ([https://sqliteonline.com/](https://sqliteonline.com/))
1. Click the book icon at the bottom right to hide the right pane
1. Click "File" and "Open DB"
1. Navigate to /data/cnf.db <!--inside the course folder you unzipped-->
1. Click "Open"
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
You should see a list of tables on the right of your screen:
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
#Good to go!
Now that we're set up, you can switch back to the slides.
We'll come back to the browser later.
</script>
</article>
</section>
<section>
<header class="slide title" data-toc>
<h1>Data</h1>
</header>
<article class="slide" data-markdown>
<script type="text/template">
#What is data?
Information technology and data are everywhere around us. In fact, more information is generated each year than was
ever produced by humanity prior to the Internet.
But, **what exactly *is* data?**
What do you think (share with the group)?
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
#Data is
* units of information/facts (people's ages, the prices of homes, etc.)
* can be structured (a shopping list, a credit card statement, etc.)
* can have a **type** (a number, some text, etc.)
* digital data: can be encoded and stored on a computer, and sent between them
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
# Uses for Data
Now that we have an idea of what data is, can you think of any common uses of data
in your daily life?
* Email: Sending and receiving textual data<!-- .element: class="delayed" -->
* Excel: Storing and analyzing data in tables<!-- .element: class="delayed" -->
* Voice calls: Exchanging audio data via phone/the Internet<!-- .element: class="delayed" -->
* Video streaming: Reading sequences of image data<!-- .element: class="delayed" -->
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
# Decolonizing Data
It is important to critically assess data by considering its source: where does this data come from? Who is controlling it?
Today's data is not exempt from bias and colonialism. Nutrition policy in Canada was informed by the scientist who authored Canada's initial Food Rules, who used data which exploited Indigenous children in residential schools by performing experiments on them.
According to Abigail Echo-Hawk, "decolonizing data means that the community itself is the one determining what is the information they want us to gather." Abigail reminds us that when collecting data, we do it in a way that truly serves our communities.
<br><br>
> <strong>Reference</strong><br><ul><li><a href="https://crosscut.com/2019/05/abigail-echo-hawk-art-and-science-decolonizing-data">Abigail Echo-Hawk on the art and science of 'decolonizing data' (Crosscut)</a></li><li><a href="https://www.cbc.ca/radio/unreserved/how-food-in-canada-is-tied-to-land-language-community-and-colonization-1.5989764/the-dark-history-of-canada-s-food-guide-how-experiments-on-indigenous-children-shaped-nutrition-policy-1.5989785">The dark history of Canada's Food Guide: How experiments on Indigenous children shaped nutrition policy (CBC)</a></li><li><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3941673/">Canada's shameful history of nutrition research on residential school children: The need for strong medical ethics in Aboriginal health research.</a></li></ul>
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
#Manipulating Data
The various ways in which we can manipulate data are best remembered with the acronym CRUD:
* **C**reate
* **R**ead
* **U**pdate
* **D**elete
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
</script>
</article>
</section>
<section>
<header class="slide title" data-toc>
<h1>Databases</h1>
</header>
<article class="slide" data-markdown>
<script type="text/template">
#What is a Database?
By this point, we have an idea of what data is, but what is a database?
* Structured data that can be queried (we can ask questions of the data)<!-- .element: class="delayed" -->
* Related data (data are linked. Ex.: a person and their job details)<!-- .element: class="delayed" -->
<div>
> There are others, but today we will learn about a common type called **relational databases!**
</div><!-- .element: class="delayed" -->
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
#Data in a Table
Here's an example of data on People, identified by social insurance numbers
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
#Relational Databases
* **Similar** data is stored in a **table**, called a **relation** (ex.: a Person table)
* Table **columns** describe **attributes** of the data (ex.: Person's name)
* Table **rows** represent a **data object** (ex.: an individual person)
* Rows are uniquely identified by an **ID** (ex.: social insurance number)
* These IDs are known as **primary keys**
</script>
</article>
<article class="slide" data-markdown>
<script type="text/template">
#Today's Database
We'll be working with **SQLite**, a simple relational database management system supporting the SQL language.
This is a free tool requiring little installation and commonly used by apps on iOS and Android.
It's a good learning tool and everything you learn will transfer to other SQL-based systems.
Now, let's dig into the SQL language!
</script>
</article>
</section>
<section>
<header class="slide title" data-toc>
<h1>SQL</h1>
</header>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Who Uses SQL?
SQL is the **most widely used** database query language today and **millions of companies** and products rely on it.
Here are a few you may know:
* Facebook
* Youtube
* Netflix
* Uber
* Twitter
Source: <a href="https://www.mysql.com/customers/industry/?id=">MySQL Clients</a>
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# That's right! SQL everywhere!
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# SQL intro
With a general understanding of databases, it's time to make use of our data!
**S**tructured **Q**uery **L**anguage (**SQL**) lets us define, modify and read our data (CRUD).
We'll focus on the part of SQL that asks questions of existing data (querying).
Let's see what that looks like!
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Anatomy of a SQL Query
A "question" to the database, formed of **clauses** (like individual sentences).
Clauses include SQL **keywords** with **column** and **table** names to locate the data.
1. `SELECT` starts the 1st clause, followed by the columns we want.
2. `FROM` starts the 2nd clause, followed by the tables holding the data.
3. `;` terminates the statement
> NOTE : SQL is **case insensitive**
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Example of a SELECT Query
This most basic query looks something like this:
```sql
SELECT FoodDescription
FROM FOOD_NAME;
```
This returns the value of `FoodDescription` for **every row** in `FOOD_NAME`.
> But what if we want all of the columns in the table? Do we have to know each of the column names?
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# SQL Wildcards
**Wildcards** are special characters (letters, numbers, etc.) that can replace any other character in a query. They're like cards that can take on any value in a card game.
We'll see two wildcards today, the first is:
* `*`, which is typically used to match any column name in a `SELECT` clause
```sql
SELECT *
FROM table_name;
```
> Other more precise wildcards exist, as described [here](https://www.w3schools.com/sql/sql_wildcards.asp).
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Exercise 1
1. Type the following query and click 
```sql
SELECT *
FROM FOOD_NAME;
```
You should see a table in the result pane below where you entered the query:
<!-- .element: class="delayed" -->
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# The WHERE Clause
What if we want to get only specific entries from our data?
The `WHERE` clause **can** follow the `FROM` clause, and allows to do this, like so:
```sql
SELECT *
FROM FOOD_NAME
WHERE column operator value;
```
Where:
1. **column** is the attribute we want to test
1. **operator** is the type of comparison (ex.: `=`, `<`, `>`, `<=`, `>=`)
1. **value** is the value we want to match (ex.: a **number**)
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Exercise 2a
Let's refine our previous query by adding a `WHERE` clause:
Use the condition `FoodID = 5` and `SELECT` only the food with ID `5` :
```sql
SELECT *
FROM FOOD_NAME
WHERE FoodID = 5;
```
<!-- .element: class="delayed" -->
<div>
The result should look like this:
</div><!-- .element: class="delayed" -->
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Exercise 2b
Design a query to `SELECT` those foods with IDs **up to and including** `10`. List your favorite food from the results in the chat!
```sql
SELECT *
FROM FOOD_NAME
WHERE FoodID <= 10;
```
<!-- .element: class="delayed" -->
<div>
The result should look like this:
</div><!-- .element: class="delayed" -->
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Matching text with LIKE
We filtered data by comparing numbers, but what if we want to search for text?
`LIKE` exists for this:
```sql
WHERE column_name LIKE "some text here"
```
1. Use `"` around the required text
2. Use `%` to match anything (wild card)
* `"apple%"` matches a string **beginning** in `"apple"`
* `"%apple"` must **end** in `"apple"`
* `"%apple%"` must contain `"apple"` **anywhere**
* `"apple"` matches that string **exactly**
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Exercise 3
Take 5 minutes to:
1. Pick a **term** to search for in the `FoodDescription` column in the `FOOD_NAME` table
2. Experiment with selecting data by matching different strings
3. Experiment with the use of wildcards
```sql
SELECT *
FROM FOOD_NAME
WHERE FoodDescription LIKE "%apple%";
```
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</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Ordering Results
Data can be ordered using the `ORDER BY` clause, following the `FROM` and `WHERE` clauses:
```sql
SELECT *
FROM my_table
ORDER BY my_column (ASC or DESC)
```
Where:
* **my_column** is the column to order by
* **(ASC or DESC)**: `ASC` to sort in ascending order, or `DESC` to sort in descending order
Let's try that out!
</script>
</article>
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# Exercise 4
Let's reuse our last query with `LIKE` to:
1. Sort elements by `FoodID`, from largest to smallest
2. Sort elements in ascending order on `FoodDescription`
```sql
SELECT FoodID, FoodGroupID, FoodSourceID, FoodDescription
FROM FOOD_NAME
WHERE FoodDescription LIKE "%apple%"
ORDER BY FoodID DESC;
```
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</script>
</article>
<article class="slide small-type" data-markdown>
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# Grouping Results
The `GROUP BY` clause combines rows and calculates total values for these groups.
```sql
GROUP BY column_name
```
Combines rows with identical values in `column_name`, or "throws them in the same bucket".
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</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
To illustrate, the following grouping of the Professors table
places results into two buckets, but what value should appear
for the value of Salary in each group?
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# SQL Functions
Functions return interesting stats on query results.
What might we want to know about the contents of a bucket grouping together many rows?
<ul>
<li>The **number of** elements in the bucket: `COUNT(*)`</li><!-- .element: class="delayed" -->
<li>The **average value** of a column: `AVG(column)`</li><!-- .element: class="delayed" -->
<li>The **sum** of a column: `SUM(column)`</li><!-- .element: class="delayed" -->
<li>The **smallest** value in a column: `MIN(column)`</li><!-- .element: class="delayed" -->
<li>The **largest** value in a column: `MAX(column)`</li><!-- .element: class="delayed" -->
</ul>
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Back to GROUP BY
How can we determine how many foods exist in each food group?
```sql
SELECT FoodGroupID, COUNT(*) AS "Foods in Group"
FROM FOOD_NAME
GROUP BY FoodGroupID;
```
Columns that appear **outside** of functions in `SELECT` normally appear in `GROUP BY`.
Other columns are calculations over the whole group.
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Joining Tables
We want to manipulate related data from **different** tables by **matching ID values**.
There are different ways to do this. We'll focus on `INNER JOIN` (or simply `JOIN`) :
```sql
SELECT columns
FROM table1 JOIN table2 ON table1.column = table2.column;
```
> For other joins, look up `OUTER JOIN` (`LEFT`, `RIGHT` or `FULL`) and `NATURAL JOIN`. Tables can also be joined in the `WHERE` clause.
</script>
</article>
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<script type="text/template">
#Related Tables
Data in two tables can be related by corresponding IDs:
</script>
</article>
<article class="slide" data-markdown>
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#Relationships
Lines in two tables can be linked together using their primary keys (PK), establishing a **relationship**. For ex.:
<ol>
<li>A line in the `PERSON` table describes `Mary`. Her PK is her SIN: `123456789`</li><!-- .element: class="delayed" -->
<li>A line in the `CITY` table describes `Montreal`. Its PK is the code: `YUL`</li><!-- .element: class="delayed" -->
<li>Values in the `HOMETOWN` column of `PERSON` **match** PKs from `CITY`</li><!-- .element: class="delayed" -->
<li>In Mary's case the value is `YUL`</li><!-- .element: class="delayed" -->
<li>Thus Mary's data links to her hometown data through this **relationship**</li><!-- .element: class="delayed" -->
</ol>
</script>
</article>
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<script type="text/template">
# Visualizing JOIN
This Venn diagram illustrates the `INNER JOIN` operation, which returns **only** those rows that have **matching values** in the chosen column in **both tables**:
> Diagrams for other types of JOINs can be seen [here](https://www.w3schools.com/sql/sql_join.asp).
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Exercise 5: Prep
In the left pane of SQLite Browser, expand the following tables to view their columns:
1. `NUTRIENT_NAME`
1. `NUTRIENT_AMOUNT`
> Which column do they have in common that would allow us to `JOIN` them on matching values?
Answer: `NutrientID`<!-- .element: class="delayed" -->
</script>
</article>
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# Exercise 5: The JOIN statement
Let's join the `NUTRIENT_NAME` and `NUTRIENT_AMOUNT` tables, to get nutrient breakdown for food ID `20` (brie cheese):
```sql
SELECT NutrientName, NutrientValue
FROM NUTRIENT_NAME
JOIN NUTRIENT_AMOUNT ON NUTRIENT_NAME.NutrientID = NUTRIENT_AMOUNT.NutrientID
WHERE NUTRIENT_AMOUNT.FoodID = 20;
```
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</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Joining more than two tables
We can join more than two tables at a time.
Let's practice by joining 3 tables to get the names of the nutrients:
```sql
SELECT NutrientName, NutrientValue, FoodDescription
FROM NUTRIENT_NAME
JOIN NUTRIENT_AMOUNT ON NUTRIENT_NAME.NutrientID = NUTRIENT_AMOUNT.NutrientID
JOIN FOOD_NAME ON FOOD_NAME.FoodID = NUTRIENT_AMOUNT.FoodID
WHERE FOOD_NAME.FoodID = 20;
```
</script>
</article>
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<script type="text/template">
# Table Aliases
A query with many repeating table names can be simplified as follows:
```sql
SELECT NutrientName, NutrientValue, FoodDescription
FROM NUTRIENT_NAME nn
JOIN NUTRIENT_AMOUNT na ON nn.NutrientID = na.NutrientID
JOIN FOOD_NAME fn ON fn.FoodID = na.FoodID
WHERE fn.FoodID = 20;
```
> Notice the use of table name **aliases** (**fn**, **na** and **nn**) to shorten the query.
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Stretch Goal: Exercise 6 (optional)
Let's get a bit more practice joining tables:
1. Take a look at the `FOOD_NAME`, `REFUSE_AMOUNT` and `REFUSE_NAME` tables
2. How can these tables be joined?
3. Select a food you like
4. Write a query to print the amounts of each type of refuse (waste) produced by a portion of that food
5. Each line should list: the **food name**, the **type of refuse**, the **amount of refuse**
</script>
</article>
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# Exercise 6: Solutions
Your query should look like:
```sql
SELECT FoodDescription, RefuseDescription, RefuseAmount
FROM FOOD_NAME fn
JOIN REFUSE_AMOUNT ra ON fn.FoodID = ra.FoodID
JOIN REFUSE_NAME rn ON ra.RefuseID = rn.RefuseID
WHERE fn.FoodID = 600;
```
<!-- .element: class="delayed" -->
<div>
The result should look like:
</div><!-- .element: class="delayed" -->
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# SQL Math
Finally, let's look at running some math on column values before returning a result!
This is useful to change a number column for reporting.
The common math operators are:
* Addition: `+`
* Subtraction: `-`
* Multiplication: `*`
* Division: `/`
* Modulo: `%` (remainder after integer division)
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
# Math Example
CNF lists nutrients for a portion of 100g. What if we want the amount/gram?
We can get nutrients/gram for brie cheese by modifying our query as follows:
```sql
SELECT NutrientName, (NutrientValue/100) AS "Nutrient per gram"
FROM FOOD_NAME fn
JOIN NUTRIENT_AMOUNT na ON fn.FoodID = na.FoodID
JOIN NUTRIENT_NAME nn ON na.NutrientID = nn.NutrientID
WHERE fn.FoodID = 20;
```
<!-- .element: class="delayed" -->
<div>
> We used a fixed number here, but we could have used another column in the calculation.
</div><!-- .element: class="delayed" -->
</script>
</article>
</section>
<section>
<header class="slide title" data-toc>
<h1>Challenge Problems</h1>
</header>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge Intro
The world of nutrition can be confusing!
As an expert in the field, you rely on data to guide the colorful characters that show up to your practice with concerns.
Try your hand at solving the following problems **with a single query** to test your SQL skills.
Don't forget to have fun!
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge 1: Critical Groups
Ms. Flamm Boyant, France's foremost food critic is visiting your city!
She has heard of Canada's intriguing "food groups" and her request is simple.
She requires:
* A list of the food groups available
* The number of foods in each group
* The groups listed from largest (most foods) to smallest
> Find her this data before she writes a bad review on social media!
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge 1 Solution
```sql
SELECT FoodGroupName, COUNT(*) AS FoodCount
FROM FOOD_NAME fn JOIN FOOD_GROUP fg
ON fn.FoodGroupID = fg.FoodGroupID
GROUP BY fg.FoodGroupID
ORDER BY FoodCount DESC;
```
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge 2: I Want my Greens
Brock O. Lee is adopting a new low-carb diet.
He requires foods matching the following criteria:
* Must be a **vegetable**
* Must include the word **green** in its description
* Must have **less than 10 grams of carbs** for a 100 gram portion
Your client wants a simple table listing all of these foods with the name of the food and the grams of carbs, from least to most.
> **Hint**: What is the food group for vegetables? What is the nutrient ID for carbs? Which 2 tables should you join in this query?
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge 2 Solution
```sql
SELECT FoodDescription, NutrientValue AS "Grams of Carbs"
FROM FOOD_NAME fn JOIN NUTRIENT_AMOUNT na ON fn.FoodID = na.FoodID
WHERE FoodGroupID = 11
AND FoodDescription LIKE "%green%"
AND NutrientID = 205
AND NutrientValue < 10
ORDER BY NutrientValue ASC;
```
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge 3: Zigzag Meal Plan
Amanda A. Appleton has always hated the letter "z".
This unusual phobic state has now resulted in a health condition, as she suffers from a zinc deficiency!
A woman her age requires `8mg` of zinc daily.
Her doctor recommends the following treatment:
* Eat foods providing **at least half** the daily requirement per 100g portion
* Eat foods containing the letter "z" n their descriptions, to desensitize yourself from the phobia
> Run a quick query to provide her with a list of suitable foods!
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge 3 Solution
```sql
SELECT FoodDescription, NutrientValue
FROM FOOD_NAME fn JOIN NUTRIENT_AMOUNT na
ON fn.FoodID = na.FoodID
WHERE NutrientID = 309
AND NutrientValue >= 4
AND FoodDescription LIKE '%z%';
```
</script>
</article>
<article class="slide small-type" data-markdown>
<script type="text/template">
#Challenge 4: No Leftovers!
Your highschool math teacher bursts through the door!