How to create category + bubble maps with Turbo Carto

query.sql

SELECT 
	*,
	7 as italians,
	3 as french,
	19 as spanish
FROM 
	populated_places
WHERE 
	name ILIKE 'Barcelona'
UNION ALL
SELECT 
	*,
	10 as italians,
	12 as french,
	4 as spanish
FROM 
	populated_places
WHERE 
	name ILIKE 'Tarragona'
UNION ALL
SELECT 
	*,
	5 as italians,
	7 as french,
	14 as spanish
FROM 
	populated_places
WHERE 
	name ILIKE 'Madrid'
    UNION ALL
SELECT 
	*,
	15 as italians,
	2 as french,
	1 as spanish
FROM 
	populated_places
WHERE 
	name ILIKE 'Zaragoza'

style.css

#layer {
  line-width: 0.1;
  marker-allow-overlap: true;
}
#layer::italians {
  	marker-width: ramp([italians], range(20, 50), jenks(4));
    marker-fill: green;
    marker-allow-overlap: true;
  	marker-opacity: 0.5;
}
#layer::french {
    marker-width: ramp([french], range(20, 50), jenks(4));
  	marker-fill: blue;
    marker-allow-overlap: true;
  	marker-opacity: 0.5;
}
#layer::spanish {
  marker-width: ramp([spanish], range(20, 50), jenks(4));
  marker-fill: red;
  marker-allow-overlap: true;
  marker-opacity: 0.5;
}