SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0efa5e8f6d9574a3c0b4dad51a67b4c6749d87a123975eac7ad6a9a130f72eea' 
  AND token = 'Nb2ypDb32//P+j7ysTADEhdyiExFsGPgJpdDNMkhdgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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