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SELECT 
  req_prod.required_id 
FROM 
  cscart_product_required_products as req_prod 
  LEFT JOIN cscart_products ON req_prod.required_id = cscart_products.product_id 
  LEFT JOIN cscart_products_categories ON req_prod.required_id = cscart_products_categories.product_id 
  LEFT JOIN cscart_categories ON cscart_products_categories.category_id = cscart_categories.category_id 
WHERE 
  req_prod.product_id = 277 
  AND cscart_products.status != 'D' 
  AND cscart_categories.company_id = 2 
GROUP BY 
  req_prod.required_id

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}