SELECT 
  cscart_promotions.bonuses, 
  cscart_promotions.conditions 
FROM 
  cscart_promotions 
  LEFT JOIN cscart_cp_fs_shipping_promo ON cscart_cp_fs_shipping_promo.promotion_id = cscart_promotions.promotion_id 
WHERE 
  cscart_cp_fs_shipping_promo.company_id = 0 
  AND cscart_promotions.status = 'A'

Query time 0.00013

JSON explain

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