private void indexZeroConstraintDocument(int docId) {
        minFeatureIndexBuilder.add((byte) 0);
        intervalEndsBuilder.add((short) Interval.ZERO_CONSTRAINT_RANGE);
        zeroConstraintDocuments.add(docId);
    }
Indexes a predicate with the given id.

@param docId     a 32-bit document id, returned in the Hit objects when the predicate matches
@param predicate the predicate to index
predicate-search/src/main/java/com/yahoo/search/predicate/PredicateIndexBuilder.java