Sandbox

SELECT 
  cscart_pages.*, 
  cscart_page_descriptions.*, 
  cscart_seo_names.name as seo_name, 
  cscart_seo_names.path as seo_path 
FROM 
  cscart_pages 
  INNER JOIN cscart_page_descriptions ON cscart_pages.page_id = cscart_page_descriptions.page_id 
  LEFT JOIN cscart_seo_names ON cscart_seo_names.object_id = cscart_pages.page_id 
  AND cscart_seo_names.type = 'a' 
  AND cscart_seo_names.dispatch = '' 
  AND cscart_seo_names.lang_code = 'en' 
WHERE 
  cscart_pages.page_id = 20 
  AND cscart_page_descriptions.lang_code = 'en' 
  AND (
    cscart_pages.usergroup_ids = '' 
    OR FIND_IN_SET(0, cscart_pages.usergroup_ids) 
    OR FIND_IN_SET(1, cscart_pages.usergroup_ids)
  ) 
  AND cscart_pages.page_type IN ('T', 'L', 'B', 'F', 'P')

Query time 0.00371

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}