SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64519cc4f4bb70241a43e0451775ec1b7327f29c3c0e3f1417703bde584672ae' 
  AND token = 'JvVLwFBInP8ZjTDWC+/fIA/MTROTHQAUbBMlYv2Wibk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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