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SELECT 
  cscart_seo_names.object_id 
FROM 
  cscart_seo_names 
  LEFT JOIN cscart_categories ON cscart_seo_names.object_id = cscart_categories.category_id 
WHERE 
  cscart_seo_names.name = 'su-radyatoru-bsg-17118617905' 
  AND cscart_seo_names.type = 'c' 
  AND cscart_categories.status in ('A', 'H') 
  AND cscart_categories.parent_id = 734

Query time 0.00028

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	cscart_seo_names	ref	PRIMARY,name,type	type	755	const,const	1	Using index condition
1	SIMPLE	cscart_categories	eq_ref	PRIMARY,parent,p_category_id	PRIMARY	3	hobilifedt.cscart_seo_names.object_id	1	Using where