SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62e0384e7238da9146a7b6a716b353d3093384ecc5f11fd924ce361d7ad593fb' 
  AND token = 'Ar0LkNbm4EMoDJEXTZF8ji8vyvTdyXBqjgZy/bkQtqw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}