Question

正如主题所说，我在Predicate字段上涉及Map<String, String>的查询时遇到问题。

我有以下测试用例重现问题：

  @Test
  public void testReferencesPredicate() throws Exception {

            //cleans the event collection
            final DBCollection event = mongoTemplate.getCollection("event");
            event.drop();

            final Event anEvent = new Event();
            //event has some more fields

            final Map<String, String> someRefs = new HashMap<>();
            someRefs.put("a", "b");
            anEvent.setReferences(someRefs);

            final Event save = this.eventRepository.save(anEvent);

            assertNotNull(save);

            final BooleanBuilder refPredicate = new BooleanBuilder();

            final Map<String, String> references = new HashMap<>();
            references.put("a", "b");

            for (final Map.Entry<String, String> stringObjectEntry : references.entrySet()) {

                final String key = stringObjectEntry.getKey();
                final String value = stringObjectEntry.getValue();

                // this also doesn't work: refPredicate.and(QEvent.event.references.contains(key, value));
                refPredicate.and(QEvent.event.references.get(key).eq(value));

            }

            final Pageable firstPage = new PageRequest(1, 1);
            final Page<Event> all = this.eventRepository.findAll(refPredicate, firstPage);
            assertNotNull(all);
            assertEquals(1, all.getContent().size());
//the eventRepository is like this: public interface EventRepository extends MongoRepository<Event, ObjectId>,
        QueryDslPredicateExecutor<Event>,

        }

当mongo登录stdout客户端正在执行的查询时，我看到以下内容：

2015-07-30T10:49:24.399+0200 I QUERY    [conn3] query some-db.event query: { references.a: "b" } planSummary: COLLSCAN ntoreturn:0 ntoskip:0 nscanned:0 nscannedObjects:1 keyUpdates:0 writeConflicts:0 numYields:0 nreturned:1 reslen:207 locks:{ Global: { acquireCount: { r: 2 } }, MMAPV1Journal: { acquireCount: { r: 1 } }, Database: { acquireCount: { r: 1 } }, Collection: { acquireCount: { R: 1 } } } 0ms

执行的查询似乎与mongo客户端的查询不同：

e = db.getCollection("event")
e.find({ "references.a": "b" })

请注意references.a周围的引号，我认为这些引号用于访问嵌套的json文档。

有人经历过这个吗？

我在mongodb v3.0.4上的spring-data-mongodb-1.7.0.RELEASE

使用spring-data-mongodb在Map <string，string =“”>字段上谓词

0 个答案: