presto-accumulo/src/main/java/io/prestosql/plugin/accumulo/AccumuloClient.java/AccumuloClient/getDefaultTabletLocation
class AccumuloClient:    private Optional<String> getDefaultTabletLocation(String fulltable)
    {
        try {
            String tableId = connector.tableOperations().tableIdMap().get(fulltable);

            // Create a scanner over the metadata table, fetching the 'loc' column of the default tablet row
            Scanner scan = connector.createScanner("accumulo.metadata", connector.securityOperations().getUserAuthorizations(username));
            scan.fetchColumnFamily(new Text("loc"));
            scan.setRange(new Range(tableId + '<'));

            // scan the entry
            Optional<String> location = Optional.empty();
            for (Entry<Key, Value> entry : scan) {
                if (location.isPresent()) {
                    throw new PrestoException(FUNCTION_IMPLEMENTATION_ERROR, "Scan for default tablet returned more than one entry");
                }

                location = Optional.of(entry.getValue().toString());
            }

            scan.close();
            return location;
        }
        catch (Exception e) {
            // Swallow this exception so the query does not fail due to being unable to locate the tablet server for the default tablet.
            // This is purely an optimization, but we will want to log the error.
            LOG.error("Failed to get tablet location, returning dummy location", e);
            return Optional.empty();
        }
    }