Vol. I · A Postgres HandbookTwelve chapters · · 756 queries

The Query & the Schema

A reading-room reference for writing PostgreSQL by hand — selects to window functions, with the schema in plain view.

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Chapters · Basic SELECT · Query 033 / 136
EasyBasic SELECT

Show customers grouped by country with count

The query

SQL
SELECT
  country,
  COUNT(*) AS customer_count
FROM customers
GROUP BY country
ORDER BY customer_count DESC;
Tested against PostgreSQL 16

Note

“GROUP BY country aggregates all customers per country. Perfect for market analysis.

Tables referenced

  • customers6 cols

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The Query & the Schema

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Compiled for Postgres 16 · MMXXVI