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SELECT 
  f.feature_id, 
  f.purpose, 
  p.product_id, 
  p.parent_product_id, 
  g.id, 
  g.code 
FROM 
  cscart_product_variation_group_features AS f 
  INNER JOIN cscart_product_variation_groups AS g ON f.group_id = g.id 
  INNER JOIN cscart_product_variation_group_products AS p ON f.group_id = p.group_id 
WHERE 
  p.product_id IN (
    102379, 102378, 102377, 102376, 102375, 
    102374, 102373, 102372, 102371, 102370, 
    102369, 102348, 102346, 102345, 102344, 
    102343, 102342, 102341, 102340, 102339
  )

Query time 0.00018

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	p	range	PRIMARY,idx_group_id	PRIMARY	3		20	Using index condition
1	SIMPLE	g	eq_ref	PRIMARY	PRIMARY	3	toolboxdigitalshop_dev.p.group_id	1
1	SIMPLE	f	ref	idx_group_id	idx_group_id	3	toolboxdigitalshop_dev.p.group_id	7