SELECT SQL_NO_CACHE *
FROM cities, (SELECT id FROM cities c USE INDEX(search_index) WHERE country_id = 212 AND title LIKE 'I%' ORDER BY id ASC LIMIT 5) t
WHERE cities.id=t.id

SELECT 
	r.id AS region_id, 
	r.title AS region_title, 
	c.id AS city_id, 
	c.title AS city_title 
FROM 
	cities c, 
	(
		SELECT 
			id 
		FROM 
			cities USE INDEX(search_index) 
		WHERE 
			country_id = 212 
			AND (
				title LIKE 'g%' 
				OR title LIKE 'г%' 
				OR title LIKE 'g%'
			) 
		ORDER BY 
			id ASC 
		LIMIT 
			5
	) t, 
	regions r, 
	countries co 
WHERE 
	c.id = t.id 
	AND r.id = c.region_id 
	AND co.id = c.country_id 
	AND co.country_code = 'ru' 
GROUP BY 
	c.id

SELECT 
	r.id AS region_id, 
	r.title AS region_title, 
	c.id AS city_id, 
	c.title AS city_title 
FROM 
	cities c, 
	(
		SELECT 
			id 
		FROM 
			cities USE INDEX(search_index) 
		WHERE 
			country_id = 212 
			AND (
				title LIKE 'g%' 
				OR title LIKE 'г%' 
				OR title LIKE 'g%'
			) 
		ORDER BY 
			id ASC 
		LIMIT 
			5
	) t, 
	regions r, 
	countries co
--->LEFT JOIN regions r ON r.id = c.region_id<----
WHERE 
	c.id = t.id 
	AND r.id = c.region_id 
	AND co.id = c.country_id 
	AND co.country_code = 'ru' 
GROUP BY 
	c.id