SELECT 
  company_id 
FROM 
  cscart_companies 
WHERE 
  1 
  AND status IN ('A', 'P', 'S', 'N')

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "1.32"
    },
    "table": {
      "table_name": "cscart_companies",
      "access_type": "ALL",
      "rows_examined_per_scan": 7,
      "rows_produced_per_join": 3,
      "filtered": "50.00",
      "cost_info": {
        "read_cost": "0.98",
        "eval_cost": "0.35",
        "prefix_cost": "1.33",
        "data_read_per_join": "21K"
      },
      "used_columns": [
        "company_id",
        "status"
      ],
      "attached_condition": "(`poscentr_upgrade422`.`cscart_companies`.`status` in ('A','P','S','N'))"
    }
  }
}