@Override
    public String getUserName() throws SQLException {
        try {
            return connection.getClient().getUser();
        } catch (Exception e) {
            throw ExceptionUtils.toSqlState(e);
        }
    }
Creates an instance of DatabaseMetaData for the given connection.


@param connection - connection for which metadata is created
@param useCatalogs - if true then getCatalogs() will return non-empty list (not implemented yet)
jdbc-v2/src/main/java/com/clickhouse/jdbc/metadata/DatabaseMetaDataImpl.java