{ "name" : "admin" }, { $set : { age : 20 } } ) 1. 2. 3. 4. upsert 这个词是 MongoDB 的一个特性,该语法的意识是更新时若无此数据则添加 db.user.update( condition , operator , upsert ) 1. upsert : true / false:为 true 时,没有则添加,为 false 时,没有不添加 db.user.upd...
官方的说明、Demo地址:https://www.mongodb.com/docs/manual/tutorial/query-array-of-documents/ 1.2 使用$elemMatch操作符查询,本文侧重该方式。 官方说明:The$elemMatchoperator matches documents that contain an array field with at least one element that matches all the specified query criteria. 就是说$...
db.t_member.update({name:"zhaomin"},{$set:{age:18}}) #不会影响其他属性列 ,主键冲突会报错 db.t_member.update({name:"zhaomin"},{$set:{age:18}},true)#第三个参数为true 则执行insertOrUpdate操作,查询出则更新,没查出则插入,或者 var p = db.t_member.findOne(); db.t_member.update(p...
AI代码解释 @RunWith(SpringRunner.class)@SpringBootTestpublicclassPersonServiceTest{@AutowiredprivateMongoTemplate mongoTemplate;/** * 自定义集合,插入文档 * @throws Exception */@TestpublicvoidinsertCustomCollection()throws Exception{Person person=newPerson();person.setId(1l);person.setUserName("张三");p...
db.collection.update( <query>, { $setOnInsert: { <field1>: <value1>, ... } }, { upsert: true } ) $set { $set: { <field1>: <value1>, ... } } $unset 删除指定字段 { $unset: { <field1>: "", ... } } $min
query, update, options ) 1. 2. 3. 4. 5. 6. 7. 修改一个或多个集合中已经存在的文档记录。这个方法可以修改一个或多个已经存在的文档记录中的指定字段,或替换整个已经存在的文档记录,具体操作由传入的参数(update parameter)决定。 默认情况下, update() 方法只修改一个文档记录。设置“Multi”选项参数后...
Learn about the query and projection operators in MongoDB. These query selectors, projection operators, and miscellaneous operators help with advanced querying and projection.
Use update operators to modify MongoDB documents. You can set field values, manipulate arrays, and more.
(9825) }, "query" : { "planCacheTotalSizeEstimateBytes" : NumberLong(0), "updateOneOpStyleBroadcastWithExactIDCount" : NumberLong(0), "multiPlanner" : { "classicCount" : NumberLong(0), "classicMicros" : NumberLong(0), "classicWorks" : NumberLong(0), "histograms" : { "classicMicros" ...
Use the positional $ operator to update the std field of the first array element that matches the grade equal to 85 condition: Important You must include the array field as part of the query document. db.students.updateOne( { _id: 4, "grades.grade": 85 }, { $set: { "grades.$.std...