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or this challenge you need to create a simple SELECT statement that will return all columns from the people table, and join to the toys table so that you can return the COUNT of the toys people table schema id name toys table schema id name people_id You should return all people fields as well as the toy count as "toy_count". Solution: SELECT p.id, p.name, COUNT(t.name) AS toy_count FROM people ..

For this challenge you need to create a simple HAVING statement, you want to count how many people have the same age and return the groups with 10 or more people who have that age. people table schema id name age return table schema age total_people Solution: SELECT age, COUNT(age) AS total_people FROM people GROUP BY age HAVING COUNT(age) >= 10 Result: age total_people 16 13 54 11 47 14 99 11 4..

You are the owner of the Grocery Store. All your products are in the database, that you have created after CodeWars SQL excercises!:) You have reached a conclusion that you waste to much time because you have to many different warehouse to visit each week. You have to find out how many different type of products you buy from each producer. If you take only few items from some of them you will st..

Overview For this kata we will be using the DVD Rental database. You are working for a company that wants to reward its top 10 customers with a free gift. You have been asked to generate a simple report that returns the top 10 customers by total amount spent ordered from highest to lowest. Total number of payments has also been requested. The query should output the following columns: customer_i..

For this challenge you need to create a simple SELECT statement that will return all columns from the people table, and join to the sales table so that you can return the COUNT of all sales and RANK each person by their sale_count. people table schema id name sales table schema id people_id sale price You should return all people fields as well as the sale count as "sale_count" and the rank as "..

You are the owner of the Grocery Store. All your products are in the database, that you have created after CodeWars SQL excercises!:) You care about local market, and want to check how many products come from United States of America or Canada. Please use SELECT statement and IN to filter out other origins. In the results show how many products are from United States of America and Canada respec..

Given a demographics table in the following format: ** demographics table schema ** id name birthday race you need to return a table that shows a count of each race represented, ordered by the count in descending order as: ** output table schema ** race count Solution: SELECT race, COUNT(id) FROM demographics GROUP BY race ORDER BY count DESC Result: race count American Indian or Alaska Native 2..

It's time to assess which of the world's greatest fighters are through to the 6 coveted places in the semi-finals of the Street Fighter World Fighting Championship. Every fight of the year has been recorded and each fighter's wins and losses need to be added up. Each row of the table fighters records, alongside the fighter's name, whether they won (1) or lost (0), as well as the type of move tha..

For this challenge you need to create a simple GROUP BY statement, you want to group all the people by their age and count the people who have the same age. people table schema id name age select table schema age [group by] people_count (people count) Solution: SELECT age, COUNT(age) AS people_count FROM people GROUP BY age Result: age people_count 8 10 4 7 1 16 5 8 3 7 0 9 9 13 6 12