presto-phoenix/src/main/java/io/prestosql/plugin/phoenix/PhoenixClient.java/PhoenixClient/listSchemas
class PhoenixClient:    @Override
    protected Collection<String> listSchemas(Connection connection)
    {
        try (ResultSet resultSet = connection.getMetaData().getSchemas()) {
            ImmutableSet.Builder<String> schemaNames = ImmutableSet.builder();
            schemaNames.add(DEFAULT_SCHEMA);
            while (resultSet.next()) {
                String schemaName = resultSet.getString("TABLE_SCHEM");
                // skip internal schemas
                if (schemaName != null && !schemaName.equalsIgnoreCase("information_schema")) {
                    schemaNames.add(schemaName);
                }
            }
            return schemaNames.build();
        }
        catch (SQLException e) {
            throw new PrestoException(PHOENIX_METADATA_ERROR, e);
        }
    }