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This query gives both the largest and the smallest, and the average donation: SELECT max(base_amount), min(base_amount), avg(base_amount) FROM donations This query determines the largest donation in our dataset: SELECT max(base_amount) FROM donations More information on these functions isĪvailable on the MySQL documentation page: Ones are MAX(), MIN(), SUM(), AVG(), STDDEV(), and COUNT(). There are many of them, but the really useful MySQL has a number of functions that allow you to calculate information. Limit is particularly useful when combined with the ORDER BY clause: SELECT id, state, metro, county FROM schools ORDER BY state LIMIT 10Ĭombining LIMIT with ORDER BY can also be used to pick a random school: SELECT id, state, metro, county FROM schools ORDER BY RAND() LIMIT 1 SELECT id, state, metro, county FROM schools LIMIT 10 Results you want before running a query on the full dataset. This is really useful to make sure you are getting the

You can limit the number of results with the LIMIT clause. You can also order them randomly: SELECT id, state, metro, county FROM schools ORDER BY RAND() You can also reverse the ordering: SELECT id, state, metro, county FROM schools ORDER BY state DESC You can sort by more than one thing: SELECT id, state, metro, county FROM schools ORDER BY state, county You can ask MySQL to sort your results by using an ORDER BY clause: SELECT id, state, metro, county FROM schools ORDER BY state You can also use * as a wildcard to select all columns: SELECT * from projects You can specify any set of columns: SELECT id, project_id FROM projectsĬolumns are returned in the order you ask for them: SELECT project_id, id FROM projects Notice that you have to specify which columns you want returned. To get information out of a database table, use the select query: SELECT id, grade_level, resource_type, total_price_excluding_optional_support, students_reached FROM projects

More information about the data is availableįrom the Donors Choose Hacking Education documentation website. The structure of the data is available in this This data is from the website Donors Choose. To connect, you will need the following information:Įveryone should already have some data in their database.

Very nice (what I use), but the full version is $75-$95