sql - Select distinct values with count in PostgreSQL -


this heavily simplified version of sql problem i'm dealing with. let's i've got table of cities in world, this:

country city ------------ canada  montreal cuba    havanna china   beijing canada  victoria china   macau

i want count how many cities each country has, end table such:

country city_count ------------------ canada  50 cuba    10 china   200

i know can distinct country values select distinct country t1 , suspect need construct subquery city_count column. non-sql brain telling me need loop through results...

thanks!

assuming reason new row unique city

select country, count(country) city_count table group country

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