SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4ec49e48a9b5bafb1618b2f25a630572484bcc730b8c69e361435462e94576c' 
  AND token = 'SUjnIskTz/rgg+wIIqZzf7alqMRbWv2RwCy/8fan2SY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00470

JSON explain

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