SELECT 
  banner_id, 
  position, 
  banner_nr, 
  url 
FROM 
  cscart_et_mv_vsb_banners 
WHERE 
  vsb_id = 509 
  AND lang_code = 'en' 
ORDER BY 
  cscart_et_mv_vsb_banners.position asc

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "2.20"
    },
    "ordering_operation": {
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "1.00"
      },
      "table": {
        "table_name": "cscart_et_mv_vsb_banners",
        "access_type": "ALL",
        "rows_examined_per_scan": 1,
        "rows_produced_per_join": 1,
        "filtered": "100.00",
        "cost_info": {
          "read_cost": "1.00",
          "eval_cost": "0.20",
          "prefix_cost": "1.20",
          "data_read_per_join": "32"
        },
        "used_columns": [
          "banner_id",
          "vsb_id",
          "banner_nr",
          "position",
          "url",
          "lang_code"
        ],
        "attached_condition": "((`webmarco`.`cscart_et_mv_vsb_banners`.`vsb_id` = 509) and (`webmarco`.`cscart_et_mv_vsb_banners`.`lang_code` = 'en'))"
      }
    }
  }
}