Sandbox

SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2f1434b3e321fc243b20aa1f9e34a1ed5fa8b9eeb0caa353d9863dde9e1ecf4e' 
  AND token = 'ISv3AgxzFQke1pnNVBqMeHksTxyIfUHijTLsOy32iq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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