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PostgreSQL training

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Software ==>	Postgres SQL (35 exercises)
Topic ==>	Aggregation and grouping (3 exercises)
Level ==>	Average difficulty
Subject ==>	PostgreSQL training

Group concerts by multiple different geographic columns and show basic aggregated statistics

This exercise is provided to allow potential course delegates to choose the correct Wise Owl Microsoft training course, and may not be reproduced in whole or in part in any format without the prior written consent of Wise Owl.

If you don't have a copy of the music_01 database, first follow the instructions at the following link to create it: https://www.wiseowl.co.uk/postgres/exercises/postgres-sql/using-postgres/5350/

Write a query using the venue and show tables to display the aggregations shown below for each venue:

Venue statistics

We've sorted the list in descending order of the count of shows.

Make another version of the same query which shows the same statistics for different cities.

Sales and shows by city

You'll need to keep the venue table in the query so that you have something to join the city table to!

Make another version of the same query which groups the data by country.

Statistics by country

The US dominates ...

Make another version of the query which groups the data by continent.

Statistics by continent

No great surprises in this list.

Create a version of the previous query which groups the data by each of the previous group fields to produce the results shown below:

Sales and stats by various columns

The final results you should see.

Save the script of More and more joins.sql and then close it.

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