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我们在使用mongo DB数据库进行查询的时候,只使用MongoRepository进行查询,实现部分复杂的查询的时候会变得有些吃力。我们可以使用MongoTemplate实现比较复杂的查询。
首先需要配置maven依赖

 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-mongodb</artifactId>
        </dependency>

配置简单的application.properties文件

#uri: mongodb://username:password@ip:port/admin
spring.data.mongodb.uri=mongodb://yin:yin@localhost:27017
spring.data.mongodb.database=xc_cms

这是事先准备好的数据

在这里插入图片描述
下面对部分常用命令进行演示

 @Autowired
    MongoTemplate mongoTemplate;
    @Override
    public JsonVO testMongoFind() {
        JsonVO jsonVO = new JsonVO(200, "success");
        //返回只返回某些字段
        Query query4 = new Query();
        query4.fields().include("valueInt").include("valueInt2");
        List<MongoTestEntity> entityList2 = mongoTemplate.find(query4, MongoTestEntity.class, "mongoTest");
        System.out.println(entityList2);
        //返回mongno不为null 或者 ""
        Query query5 = new Query();
        List<String> testLst = new ArrayList<>();
        testLst.add("");
        testLst.add(null);
        query5.addCriteria(Criteria.where("valueStr").nin(testLst));
        List<MongoTestEntity> entityList3 = mongoTemplate.find(query5, MongoTestEntity.class, "mongoTest");
        System.out.println(entityList3);
        //模糊查询
        Query query6 = new Query();
        //如果有特殊符号使用转义符
        query6.addCriteria(Criteria.where("valueStr").regex(".*?" +"hao"+ ".*"));
        List<MongoTestEntity> entityList4 = mongoTemplate.find(query6, MongoTestEntity.class, "mongoTest");
        System.out.println(entityList4);
        //分页排序
        int pageNum = 2;
        int pageSize = 3;
        int start = (pageNum - 1) * pageSize;
        Query query = new Query();
        query.with(Sort.by(Sort.Direction.DESC, "valueInt"));
        query.skip(start).limit(pageSize);
        List<MongoTestEntity> entityList = mongoTemplate.find(query, MongoTestEntity.class, "mongoTest");
        //计算总数
        long mongoTestNum = mongoTemplate.count(query, MongoTestEntity.class, "mongoTest");
        System.out.println(mongoTestNum);
        //复杂sql的转化(in/and/or/大于/小于/等于)
        //select * from mongoTest where valueStr in ("nihao","dajiahao")
        // and valueInt>=2 and (valueInt2 =15 or time>= (now -interval 5 day))
        Query query2 = new Query();
        Criteria criteria =new Criteria();
        List<String> valueStrParam = new ArrayList<>();
        valueStrParam.add("nihao");
        valueStrParam.add("dajiahao");
        criteria.and("valueStr").in(valueStrParam).andOperator(Criteria.where("valueInt").gte(2)).
                orOperator(Criteria.where("valueInt2").is(15), Criteria.where("time")
                        .gte(LocalDateTime.now().minus(5, ChronoUnit.DAYS)));
        query2.addCriteria(criteria);
        List<MongoTestEntity> entityList1 = mongoTemplate.find(query2, MongoTestEntity.class, "mongoTest");
        System.out.println(entityList1);
        //进行聚合操作  select count(valueStr) as count,valueStr as valueStr ,sum(valueInt2) as valueInt2 from mongoTest group by valueStr
        Aggregation aggregation = Aggregation.newAggregation(Aggregation.group("valueStr").count().as("count").
                first("valueStr").as("valueStr").sum("valueInt2").as("valueInt2"))
                ///Aggregation.newAggregationOptions().allowDiskUse(true)是用来解除mongodb 查询数据默认占用最大内存的(默认100M).不然会抛出异常:
                .withOptions(Aggregation.newAggregationOptions().allowDiskUse(true).build());
        AggregationResults<AggregationVO> aggregateFrist = mongoTemplate.aggregate(aggregation, "mongoTest", AggregationVO.class);
        List<AggregationVO> mappedResults = aggregateFrist.getMappedResults();
        System.out.println(mappedResults);
        jsonVO.setData(entityList);
        return jsonVO;

用mongoTemplate做更改

 @Override
    public JsonVO upsetMongoTest(MongoTestEntity mongoTestEntity){
        String result = "";
        String str = mongoTestEntity.getValueStr();
        Query query = new Query();
        query.addCriteria(Criteria.where("valueStr").is(str));
        org.bson.Document document = new org.bson.Document();
        mongoTemplate.getConverter().write(mongoTestEntity,document);
        Update update = Update.fromDocument(document);
        UpdateResult upsert = mongoTemplate.upsert(query, update, MongoTestEntity.class, "mongoTest2");
        if (upsert.getMatchedCount() > 0) {
            System.out.println("--------------:数据更改");
            result = "数据更改";
        }else {
            System.out.println("-----------:数据插入");
            result = "数据插入";
        return new JsonVO(200, "success", result);

采用另外一种方式来查询更改

* 测试查询更改 @Override public void testUpdate() { int pageNum = 1; int pageSize = 10; Sort sort = Sort.by(Sort.Direction.DESC, "valueInt"); PageRequest pageRequest = PageRequest.of(pageNum - 1, pageSize, sort); Query query = new Query(); query.addCriteria(createCriteria()); List<MongoTestEntity> mongoTest = mongoTemplate.find(query.with(pageRequest), MongoTestEntity.class, "mongoTest"); System.out.println(mongoTest); Update update = new Update(); update.set("valueStr2", "haohao"); update.set("time", LocalDateTime.now()); Query query2 = new Query(); query2.addCriteria(createCriteria()); mongoTemplate.updateMulti(query2, update, "mongoTest"); * 添加条件 * @return private Criteria createCriteria(){ Criteria criteria = new Criteria(); ArrayList<String> valueStrLst = new ArrayList<>(); valueStrLst.add("nihao"); valueStrLst.add("wohao"); criteria.and("valueStr").in(valueStrLst); criteria.and("valueStr2").is("wohao"); return criteria;

附上使用的vo类

@Data
public class MongoTestEntity {
    private String id;
    private Integer valueInt;
    private Integer valueInt2;
    private String valueStr;
    private LocalDateTime time;
@Data
public class AggregationVO {
    private String valueStr;
    private Integer count;
    private Integer valueInt2;

附上使用插入数据的代码

   @Override
    public JsonVO insertData(){
        JsonVO jsonVO = new JsonVO(200, "success");
        List<MongoTestEntity> entityList = new ArrayList<>();
        MongoTestEntity mongoTestEntity = new MongoTestEntity();
        mongoTestEntity.setValueInt(1);
        mongoTestEntity.setValueInt2(11);
        mongoTestEntity.setValueStr("nihao");
        mongoTestEntity.setTime( LocalDateTime.now().minus(10, ChronoUnit.HOURS));
        entityList.add(mongoTestEntity);
        MongoTestEntity mongoTestEntity2 = new MongoTestEntity();
        mongoTestEntity2.setValueInt(1);
        mongoTestEntity2.setValueInt2(15);
        mongoTestEntity2.setValueStr("wohao");
        mongoTestEntity2.setTime( LocalDateTime.now().minus(15, ChronoUnit.HOURS));
        entityList.add(mongoTestEntity2);
        MongoTestEntity mongoTestEntity3 = new MongoTestEntity();
        mongoTestEntity3.setValueInt(5);
        mongoTestEntity3.setValueInt2(15);
        mongoTestEntity3.setValueStr("dajiahao");
        mongoTestEntity3.setTime( LocalDateTime.now().minus(5, ChronoUnit.HOURS));
        entityList.add(mongoTestEntity3);
        MongoTestEntity mongoTestEntity4 = new MongoTestEntity();
        mongoTestEntity4.setValueInt(5);
        mongoTestEntity4.setValueInt2(15);
        mongoTestEntity4.setTime( LocalDateTime.now().minus(5, ChronoUnit.HOURS));
        entityList.add(mongoTestEntity4);
        mongoTemplate.insert(entityList, "mongoTest");
        return jsonVO;
                    我们在使用mongo DB数据库进行查询的时候,只使用MongoRepository进行查询,实现部分复杂的查询的时候会变得有些吃力。我们可以使用MongoTemplate实现比较复杂的查询。首先需要配置maven依赖 &lt;dependency&gt;            &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; ...
     SpringData  MongoDB提供了org.springframework.data.mongodb.core.MongoTemplate对MongoDB的find的操作,我们上一篇介绍了基本文档的查询,我们今天介绍分页查询,分页查询返回到匹配文档的游标,可以随意修改查询限制、跳跃、和排序顺序的功能。
     我们在查询时find()方法接受Query类型...
{$and : [{ARV_APT: "PEK"}, {$and: [{FLT_DATE: {$gte: "20180101"}}, {FLT_DATE: {$lte: "20180104"}}]}]}
然后传给后端进行查询,将结果返回。
之前使用mongodb进行CRUD的时候都是基于API的
1:使用...
    public void specialFieldQuery() {
        Query query = new Query(Criteria.where("user").is("用户名blog"));
        // 查询一条满足条件的数据
        Map result = mongoTemplate.findOne(query, Map.class
参数说明:sql(Operators)
  where ($match) 、group by ($group)、having($match)、select($project)、order by($sort)、limit($limit)
  sum($sum)、count($sum)、join($lookup)
* project:列出所有本次查询字段,包括查询条件的字段和需要搜索的字段;
* match:搜索条件criteria
* un...
@Document("Schedule")
@Accessors(chain = true)
public class Schedule extends BaseMongoEntity {
	private static final long serialVersionUID = 1L;
	@ApiModelProperty(value = "医院编号")
	@Indexed //.
				
使用 Spring Data MongoDB时,我们可能需要限制从数据库对象映射的属性。通常,出于安全原因,我们可能需要这样做—以避免暴露存储在服务器上的敏感信息。或者,例如,我们可能需要过滤掉 Web 应用程序中显示的部分数据。 在这个简短的教程中,我们将看到 MongoDB 如何应用字段限制。
@Repository public interface MsgRecordRepository extends MongoRepository<MsgCollection, String> { @Query(fields = "{'message.msgId' : 1,'message.templateTypeId' : 1,'message.msgType' : 1,'...
query.addCriteria(new Criteria() .andOperator(criteria, new Criteria() .orOperator(Criteria.where(BatteryRealtimeInfo.BatteryRealtimeInfoEnum.updateTime.name()) .lt(LocalDateTime.ofInstant(Instant.ofEpochMilli(now -.
```java import org.springframework.data.mongodb.core.MongoTemplate; import org.springframework.data.mongodb.core.aggregation.Aggregation; import org.springframework.data.mongodb.core.aggregation.TypedAggregation; import org.springframework.data.mongodb.core.aggregation.AggregationResults; import static org.springframework.data.mongodb.core.aggregation.Aggregation.*; public class AggregationExample { private MongoTemplate mongoTemplate; public AggregationExample(MongoTemplate mongoTemplate) { this.mongoTemplate = mongoTemplate; public void performAggregation() { TypedAggregation aggregation = newAggregation( // 添加聚合操作 match(Criteria.where("fieldName").is("value")), group("groupField").count().as("count"), sort(Sort.Direction.DESC, "count") AggregationResults<AggregateResultClass> results = mongoTemplate.aggregate(aggregation, "collectionName", AggregateResultClass.class); List<AggregateResultClass> resultList = results.getMappedResults(); // 处理结果 for (AggregateResultClass result : resultList) { // 进行相应的操作 // result.getGroupField(); // result.getCount(); // 聚合结果的POJO类 class AggregateResultClass { private String groupField; private int count; // 省略构造函数、getter和setter 请根据您的具体需求修改上述示例中的字段和条件。希望对您有所帮助!如果您有任何其他问题,请随时提问。 //输出list System.out.println("list:"+list); System.out.println("arrays:"+list.getClass().getSimpleName()); 批量删除时用得到,不用谢 k8s Master节点和Node节点上各组件和核心概念的介绍 远方 hi: 不能说一点用没有,是一点用都没有