private Map<String, Integer> createFieldPositionMap() {
        final Map<String, Integer> fieldPositionMap = new HashMap<>();
        int i = 0;
        for (final StatisticField field : fields) {
            fieldPositionMap.put(field.getFieldName(), i++);
        }
        return fieldPositionMap;
    }
Held in a set to prevent duplicates.
<p>
XMLTransient to force JAXB to use the setter
stroom-core-shared/src/main/java/stroom/statistics/impl/sql/shared/StatisticsDataSourceData.java