SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc83b944a243d10a9a4e08a2c35c8326460133feb663cafd3db710b3e2dba03b' 
  AND token = 'uCcsKdY/Y3HBDNICoCPHeUZoMvfhdsVz3SWcDSa5FVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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