Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dcbdb15ac0349a3c29f8b57e65d8df6336d3643059e0d556aeadaa66c6dbe79' 
  AND token = 'uDy5yaSbNmYQV/7XmR+yTBzN6c81NtQLbPNW+6gr3Zc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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