SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd202b915fa720e63f09c6966f31a9317759a0803977368ef86090e31d52daaa7' 
  AND token = 'HOedx3Vm0JCYdtgtV+vir3YZApPfPh5D/KZholMW1tA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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