使用MongRepository
public interface VideoRepository extends MongoRepository<Video, String> {
Video findVideoById(String id);
// 视频分页预览{title,coverImg}
Page<Video> findByGradeAndCourse(Grade grade, Course course, Pageable page);
}
- 问题
- 动态条件查询?
- 只查询指定字段?
- 指定字段
@Query(fields = "{'title':1, 'coverImg':1, 'course':1}")
Page<Video> findBy(Criteria where, Pageable page);
- 指定条件
DBObject obj = new BasicDBObject();
obj.put("userId", new BasicDBObject("$gte", 2));
BasicDBObject fieldsObject = new BasicDBObject();
fieldsObject.put("userId", 1);
fieldsObject.put("name", 1);
Query query = new BasicQuery(obj.toString(), fieldsObject.toString());
- demo,使用MongoTemplate,Query,DBObject
@Override
public Result getVideos(Pageable page, Long gradeId, Long courseId) {
DBObject obj = new BasicDBObject();
if(gradeId!=null&&gradeId!=0){
obj.put("grade.id", gradeId);
}
if(gradeId!=null&&gradeId!=0){
obj.put("course.id", courseId);
}
obj.put("course.id", 2);
// obj.put("course.id", new BasicDBObject("$gte", 2));
BasicDBObject fieldsObject = new BasicDBObject();
fieldsObject.put("title", 1);
fieldsObject.put("coverImg", 1);
fieldsObject.put("course", 1);
Query query = new BasicQuery(obj.toString(), fieldsObject.toString());
query.skip(page.getOffset()).limit(page.getPageSize());
List<Video> videos = mongoTemplate.find(query, Video.class);
// 总个数
long count = mongoTemplate.count(query, Video.class);
Page<Video> result = new PageImpl<Video>(videos, page, count);
return Result.success(videos);
}
查询条件对于属性是对象(course)无法生效,该方法还是不可行
混合 (终极法器)
本质上还是使用MongoTemplate来实现的,MongoRepository能实现查询指定字段,但是不能实现动态条件查询。
MongoTemplate的find方法接收Query参数,Query可以实现动态字段,但是动态条件不是普适应的(我还没找到),对于对象属性无法查询。但是Query有一个addCriteria方法,该方法可以将Example融合到Query中。因此find方法使用了Example的动态查询,Query的动态字段查询。
- VidoeOperations
public interface VideoOperations {
Page<Video> findAllPage(Example<Video> example, DBObject fields, Pageable page);
}
- VideoRepository
public interface VideoRepository extends MongoRepository<Video, String>, VideoOperations {
Video findVideoById(String id);
}
- VideoRepositoryImpl
public class VideoRepositoryImpl implements VideoOperations {
@Autowired
private MongoTemplate mongoTemplate;
@Override
public Page<Video> findAllPage(Example<Video> example, DBObject fields, Pageable page) {
Query query = new BasicQuery(null, fields.toString());
query.addCriteria((new Criteria()).alike(example));
query.with(page);
// Query q = (new Query((new Criteria()).alike(example))).with(page);
List<Video> list = mongoTemplate.find(query, example.getProbeType());
return PageableExecutionUtils.getPage(list, page, () -> {
return mongoTemplate.count(query, example.getProbeType());
});
}
}
Keyword | Sample | Logical result |
---|---|---|
After |
findByBirthdateAfter(Date date) |
{"birthdate" : {"$gt" : date}} |
GreaterThan |
findByAgeGreaterThan(int age) |
{"age" : {"$gt" : age}} |
GreaterThanEqual |
findByAgeGreaterThanEqual(int age) |
{"age" : {"$gte" : age}} |
Before |
findByBirthdateBefore(Date date) |
{"birthdate" : {"$lt" : date}} |
LessThan |
findByAgeLessThan(int age) |
{"age" : {"$lt" : age}} |
LessThanEqual |
findByAgeLessThanEqual(int age) |
{"age" : {"$lte" : age}} |
Between |
findByAgeBetween(int from, int to) |
{"age" : {"$gt" : from, "$lt" : to}} |
In |
findByAgeIn(Collection ages) |
{"age" : {"$in" : [ages…]}} |
NotIn |
findByAgeNotIn(Collection ages) |
{"age" : {"$nin" : [ages…]}} |
IsNotNull , NotNull |
findByFirstnameNotNull() |
{"firstname" : {"$ne" : null}} |
IsNull , Null |
findByFirstnameNull() |
{"firstname" : null} |
Like , StartingWith , EndingWith |
findByFirstnameLike(String name) |
{"firstname" : name} (name as regex) |
NotLike , IsNotLike |
findByFirstnameNotLike(String name) |
{"firstname" : { "$not" : name }} (name as regex) |
Containing on String |
findByFirstnameContaining(String name) |
{"firstname" : name} (name as regex) |
NotContaining on String |
findByFirstnameNotContaining(String name) |
{"firstname" : { "$not" : name}} (name as regex) |
Containing on Collection |
findByAddressesContaining(Address address) |
{"addresses" : { "$in" : address}} |
NotContaining on Collection |
findByAddressesNotContaining(Address address) |
{"addresses" : { "$not" : { "$in" : address}}} |
Regex |
findByFirstnameRegex(String firstname) |
{"firstname" : {"$regex" : firstname }} |
(No keyword) |
findByFirstname(String name) |
{"firstname" : name} |
Not |
findByFirstnameNot(String name) |
{"firstname" : {"$ne" : name}} |
Near |
findByLocationNear(Point point) |
{"location" : {"$near" : [x,y]}} |
Near |
findByLocationNear(Point point, Distance max) |
{"location" : {"$near" : [x,y], "$maxDistance" : max}} |
Near |
findByLocationNear(Point point, Distance min, Distance max) |
{"location" : {"$near" : [x,y], "$minDistance" : min, "$maxDistance" : max}} |
Within |
findByLocationWithin(Circle circle) |
{"location" : {"$geoWithin" : {"$center" : [ [x, y], distance]}}} |
Within |
findByLocationWithin(Box box) |
{"location" : {"$geoWithin" : {"$box" : [ [x1, y1], x2, y2]}}} |
IsTrue , True |
findByActiveIsTrue() |
{"active" : true} |
IsFalse , False |
findByActiveIsFalse() |
{"active" : false} |
Exists |
findByLocationExists(boolean exists) |
{"location" : {"$exists" : exists }} |