java 中mongodb的各种操作查询的实例详解

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 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 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 getProcessLandLogs(int begin,int end,List 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 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 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 findAllBykeyA(String keyA); 

5. 查询数量:----- 关键字---count

 public long getPageInfosCount(List 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 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 fields = new ArrayList(); 
      List