Sharing various examples of mongodb operation query in Java
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java 中mongodb的各种操作查询的实例详解
一. 常用查询:
1. 查询一条数据:(多用于保存时判断db中是否已有当前数据,这里 is 精确匹配,模糊匹配 使用regex...)
public PageUrl getByUrl(String url) { return findOne(new Query(Criteria.where("url").is(url)),PageUrl.class); }
2. 查询多条数据:linkUrl.id 属于分级查询
public List<PageUrl> getPageUrlsByUrl(int begin, int end,String linkUrlid) { Query query = new Query(); query.addCriteria(Criteria.where("linkUrl.id").is(linkUrlid)); return find(query.limit(end - begin).skip(begin), PageUrl.class); }
3.模糊查询:-----关键字---regex
public long getProcessLandLogsCount(List<Condition> conditions) { Query query = new Query(); if (conditions != null && conditions.size() > 0) { for (Condition condition : conditions) { query.addCriteria(Criteria.where(condition.getKey()).regex(".*?\\" +condition.getValue().toString()+ ".*")); } } return count(query, ProcessLandLog.class); }
最下面,我在代码亲自实践过的模糊查询,只支持字段属性是字符串的查询,你要是查字段属性是int的模糊查询,还真没辙。
4.gte: 大于等于,lte小于等于...注意查询的时候各个字段的类型要和mongodb中数据类型一致
public List<ProcessLandLog> getProcessLandLogs(int begin,int end,List<Condition> conditions,String orderField,Direction direction) { Query query = new Query(); if (conditions != null && conditions.size() > 0) { for (Condition condition : conditions) { if(condition.getKey().equals("time")){ query.addCriteria(Criteria.where("time").gte(condition.getValue())); //gte: 大于等于 }else if(condition.getKey().equals("insertTime")){ query.addCriteria(Criteria.where("insertTime").gte(condition.getValue())); }else{ query.addCriteria(Criteria.where(condition.getKey()).is(condition.getValue())); } } } return find(query.limit(end - begin).skip(begin).with(new Sort(new Sort.Order(direction, orderField))), ProcessLandLog.class); } public List<DpsLand> getDpsLandsByTime(int begin, int end, Date beginDate,Date endDate) { return find(new Query(Criteria.where("updateTime").gte(beginDate).lte(endDate)).limit(end - begin).skip(begin), DpsLand.class); }
查询字段不存在的数据 -----关键字---not
public List<GoodsDetail> getGoodsDetails2(int begin, int end) { Query query = new Query(); query.addCriteria(Criteria.where("goodsSummary").not()); return find(query.limit(end - begin).skip(begin),GoodsDetail.class); }
查询字段不为空的数据 -----关键字---ne
Criteria.where("key1").ne("").ne(null)
查询或语句:a || b ----- 关键字---orOperator
Criteria criteria = new Criteria(); criteria.orOperator(Criteria.where("key1").is("0"),Criteria.where("key1").is(null));
查询且语句:a && b ----- 关键字---and
Criteria criteria = new Criteria(); criteria.and("key1").is(false); criteria.and("key2").is(type); Query query = new Query(criteria); long totalCount = this.mongoTemplate.count(query, Xxx.class);
查询一个属性的子属性,例如:查下面数据的key2.keyA的语句
var s = { key1: value1, key2: { keyA: valueA, keyB: valueB } }; @Query("{'key2.keyA':?0}") List<Asset> findAllBykeyA(String keyA);
5. 查询数量:----- 关键字---count
public long getPageInfosCount(List<Condition> conditions) { Query query = new Query(); if (conditions != null && conditions.size() > 0) { for (Condition condition : conditions) { query.addCriteria(Criteria.where(condition.getKey()).is(condition.getValue())); } } return count(query, PageInfo.class); }
查找包含在某个集合范围:----- 关键字---in
Criteria criteria = new Criteria(); Object [] o = new Object[]{0, 1, 2}; //包含所有 criteria.and("type").in(o); Query query = new Query(criteria); query.with(new Sort(new Sort.Order(Direction.ASC, "type"))).with(new Sort(new Sort.Order(Direction.ASC, "title"))); List<WidgetMonitor> list = this.mongoTemplate.find(query, WidgetMonitor.class);
6. 更新一条数据的一个字段:
public WriteResult updateTime(PageUrl pageUrl) { String id = pageUrl.getId(); return updateFirst(new Query(Criteria.where("id").is(id)),Update.update("updateTime", pageUrl.getUpdateTime()), PageUrl.class); }
7. 更新一条数据的多个字段:
//调用更新 private void updateProcessLandLog(ProcessLandLog processLandLog, int crawlResult) { List<String> fields = new ArrayList<String>(); List<Object> values = new ArrayList<Object>(); fields.add("state"); fields.add("result"); fields.add("time"); values.add("1"); values.add(crawlResult); values.add(Calendar.getInstance().getTime()); processLandLogReposity.updateProcessLandLog(processLandLog, fields, values); } //更新 public void updateProcessLandLog(ProcessLandLog land, List<String> fields,List<Object> values) { Update update = new Update(); int size = fields.size(); for(int i = 0 ; i < size; i++){ String field = fields.get(i); Object value = values.get(i); update.set(field, value); } updateFirst(new Query(Criteria.where("id").is(land.getId())), update,ProcessLandLog.class); }
8. 删除数据:
public void deleteObject(Class<T> clazz,String id) { remove(new Query(Criteria.where("id").is(id)),clazz); }
9.保存数据:
//插入一条数据 public void saveObject(Object obj) { insert(obj); } //插入多条数据 public void saveObjects(List<T> objects) { for(T t:objects){ insert(t); } }
我自己使用的例子:
下面例子涉及到:
精确查询:is;
模糊查询:regex;
分页查询,每页多少:skip,limit
按某个字段排序(或升或降):new Sort(new Sort.Order(Sort.Direction.ASC, "port"))
查询数量:count
public Map<String, Object> getAppPortDetailByPage(int pageNo, int pageSize, String order, String sortBy, String appPortType, String appPortSeacherName) { Criteria criteria = new Criteria(); if (!appPortType.equals("")) { if (!appPortType.equals("all")) { //DB表里的字段----appmanageType //下同 port protocol 也是DB表的字段 criteria.and("appmanageType").is(appPortType); } } if (!appPortSeacherName.equals("")) { try { criteria.orOperator(Criteria.where("port").is(Integer.parseInt(appPortSeacherName)), Criteria.where("protocol").regex(".*?" + appPortSeacherName + ".*")); }catch (Exception e){ criteria.orOperator(Criteria.where("protocol").regex(".*?" + appPortSeacherName + ".*")); } } Map<String, Object> result = Maps.newHashMap(); Query query = new Query(criteria); query.skip((pageNo - 1) * pageSize); query.limit(pageSize); if(order != null && sortBy != null){ query.with(new Sort(new Sort.Order(order.equals("asc") ? Sort.Direction.ASC : Sort.Direction.DESC, sortBy))); }else { query.with(new Sort(new Sort.Order(Sort.Direction.ASC, "port"))); } List<Appportmanage> list = this.mongoTemplate.find(query, Appportmanage.class); long count = this.mongoTemplate.count(query, Appportmanage.class); result.put("datas", list); result.put("size", count); return result; }
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