SELECT 
  cscart_ab__video_gallery.video_id, 
  cscart_ab__video_gallery.product_id, 
  cscart_ab__video_gallery.status, 
  cscart_ab__video_gallery.pos, 
  cscart_ab__video_gallery.icon_type, 
  cscart_ab__video_gallery_descriptions.youtube_id, 
  cscart_ab__video_gallery_descriptions.title, 
  cscart_ab__video_gallery_descriptions.description 
FROM 
  cscart_ab__video_gallery 
  LEFT JOIN cscart_ab__video_gallery_descriptions ON cscart_ab__video_gallery_descriptions.video_id = cscart_ab__video_gallery.video_id 
  AND cscart_ab__video_gallery_descriptions.lang_code = 'en' 
WHERE 
  cscart_ab__video_gallery.product_id = 309503 
  AND cscart_ab__video_gallery.status = "A" 
ORDER BY 
  cscart_ab__video_gallery.pos ASC

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "2.40"
    },
    "ordering_operation": {
      "using_filesort": true,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_ab__video_gallery",
            "access_type": "ref",
            "possible_keys": [
              "status",
              "product_id"
            ],
            "key": "product_id",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "ref": [
              "const"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 1,
            "filtered": "100.00",
            "index_condition": "(`webmarco`.`cscart_ab__video_gallery`.`product_id` <=> 309503)",
            "cost_info": {
              "read_cost": "1.00",
              "eval_cost": "0.20",
              "prefix_cost": "1.20",
              "data_read_per_join": "64"
            },
            "used_columns": [
              "video_id",
              "product_id",
              "pos",
              "status",
              "icon_type"
            ],
            "attached_condition": "(`webmarco`.`cscart_ab__video_gallery`.`status` = 'A')"
          }
        },
        {
          "table": {
            "table_name": "cscart_ab__video_gallery_descriptions",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "video_id",
              "lang_code"
            ],
            "key_length": "9",
            "ref": [
              "webmarco.cscart_ab__video_gallery.video_id",
              "const"
            ],
            "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": "2.40",
              "data_read_per_join": "840"
            },
            "used_columns": [
              "video_id",
              "youtube_id",
              "title",
              "description",
              "lang_code"
            ]
          }
        }
      ]
    }
  }
}