public Map<String, SummaryField> getUniqueNamedSummaryFields() {
        Map<String, SummaryField> summaryFields = inherited.isPresent() ? requireInherited().getUniqueNamedSummaryFields()
                                                                        : new java.util.LinkedHashMap<>();
        for (DocumentSummary documentSummary : summaries.values()) {
            for (SummaryField summaryField : documentSummary.getSummaryFields().values()) {
                summaryFields.put(summaryField.getName(), summaryField);
            }
        }
        return summaryFields;
    }
Returns one summary field for each summary field name. If there are multiple summary fields with the same
name, the last one will be used. Multiple fields of the same name should all have the same content in a valid
search definition, except from the destination set. So this method can be used for all summary handling except
processing the destination set. The map becomes owned by the receiver.
config-model/src/main/java/com/yahoo/schema/Schema.java