SELECT 
  * 
FROM 
  cscart_banner_images 
WHERE 
  banner_id IN (42, 48) 
  AND lang_code = 'en'

Query time 0.00115

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "4.81"
    },
    "table": {
      "table_name": "cscart_banner_images",
      "access_type": "range",
      "possible_keys": [
        "banner_layer",
        "banner_id"
      ],
      "key": "banner_layer",
      "used_key_parts": [
        "banner_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 2,
      "rows_produced_per_join": 0,
      "filtered": "10.00",
      "index_condition": "((`pankajecarter_systemtwo`.`cscart_banner_images`.`banner_id` in (42,48)) and (`pankajecarter_systemtwo`.`cscart_banner_images`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "4.77",
        "eval_cost": "0.04",
        "prefix_cost": "4.81",
        "data_read_per_join": "33"
      },
      "used_columns": [
        "banner_image_id",
        "banner_id",
        "layer_key",
        "lang_code"
      ]
    }
  }
}