SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dafeceffc6e1809845903a622ef76d165297d07037484aaa4b84e96ea8651dae' 
  AND token = 'KEKiLlZONs02ONhKRv9ynt0NUX7tvzxgxRHQ9/YgQWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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