SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '832fde9b83856f00476561c57aaf2fe84bd5abf77390047f57c31258d6f50fa9' 
  AND token = 'mLw1dgbeZgmVJn+0fNCgVIlACZYI5GWV3NU8ViSfrmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}