SELECT 
  * 
FROM 
  cscart_abt__ut2_less_settings 
WHERE 
  style = '3tabs.less'

Query time 0.00058

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.0304148,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_abt__ut2_less_settings",
          "access_type": "ALL",
          "loops": 1,
          "rows": 120,
          "cost": 0.0304148,
          "filtered": 100,
          "attached_condition": "cscart_abt__ut2_less_settings.style = '3tabs.less'"
        }
      }
    ]
  }
}