SELECT 
  params 
FROM 
  cscart_cp_blog_categories 
WHERE 
  category_id = 2

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "1.00"
    },
    "table": {
      "table_name": "cscart_cp_blog_categories",
      "access_type": "const",
      "possible_keys": [
        "PRIMARY"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "category_id"
      ],
      "key_length": "3",
      "ref": [
        "const"
      ],
      "rows_examined_per_scan": 1,
      "rows_produced_per_join": 1,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "0.00",
        "eval_cost": "0.20",
        "prefix_cost": "0.00",
        "data_read_per_join": "1K"
      },
      "used_columns": [
        "category_id",
        "params"
      ]
    }
  }
}

Result

params
a:3:{s:24:"show_subcategories_posts";s:1:"Y";s:16:"posts_list_style";s:4:"grid";s:9:"list_vars";a:7:{s:4:"list";a:3:{s:15:"list_show_image";s:1:"Y";s:16:"list_image_width";s:3:"300";s:17:"list_image_height";s:3:"250";}s:5:"list2";a:6:{s:15:"list_show_image";s:1:"Y";s:16:"list_image_width";s:3:"140";s:17:"list_image_height";s:3:"140";s:19:"separate_for_mobile";s:1:"Y";s:16:"mobile_img_width";s:3:"350";s:17:"mobile_img_height";s:3:"200";}s:10:"large_list";a:3:{s:15:"list_show_image";s:1:"Y";s:16:"list_image_width";s:3:"300";s:17:"list_image_height";s:3:"250";}s:4:"grid";a:4:{s:12:"grid_columns";s:1:"3";s:15:"list_show_image";s:1:"Y";s:16:"list_image_width";s:3:"300";s:17:"list_image_height";s:3:"250";}s:6:"grid_2";a:4:{s:12:"grid_columns";s:1:"3";s:15:"list_show_image";s:1:"Y";s:16:"list_image_width";s:3:"350";s:17:"list_image_height";s:3:"350";}s:18:"simplified_masonry";a:1:{s:15:"list_show_image";s:1:"Y";}s:12:"grid_netpeak";a:4:{s:12:"grid_columns";s:1:"3";s:15:"list_show_image";s:1:"Y";s:16:"list_image_width";s:3:"300";s:17:"list_image_height";s:3:"250";}}}