更新的两种方法 1替换更新：会覆盖原数据 2操作符更新：不会覆盖原数据 性能更好 原子性操作 update() 方法用于更新已存在的文档。语法格式如下： db.collection.update(
更新的两种方法
1替换更新：会覆盖原数据
2操作符更新：不会覆盖原数据 性能更好 原子性操作
update() 方法用于更新已存在的文档。语法格式如下：
db.collection.update( <query>, <update>, { upsert: <boolean>, multi: <boolean>, writeConcern: <document> } )参数说明：
query : update的查询条件，类似sql update查询内where后面的；
update : update的对象和一些更新的操作符（如$,$inc...）等，也可以理解为sql update查询内set后面的
upsert : 可选，这个参数的意思是，如果不存在update的记录，是否插入objNew,true为插入，默认是false，不插入。
multi : 可选，mongodb 默认是false,只更新找到的第一条记录，如果这个参数为true,就把按条件查出来多条记录全部更新。
writeConcern :可选，写安全配置。
更新选择器
新增数据拿不到ObjectID？
使用insert增加数据返回值是什么？
var insert = db.users.insert({"username":"ruolan"})
使用upsert属性，让update变成insert
db.users.update({"":""},{"username":"leilei"},{"upsert":true})
建议：
不要用objectID作为系统中检索数据的条件
update中的query加在有索引的字段
更新示例
删除字段示例
db.users.updateMany({"username":"lison"},{"$unset":{"country":"","age":""}})
更新字段名称示例
db.users.updateMany({"username":"jack"},{"$rename":{"country":"guojia","age":"nianling"}})
$each作用示例 无each会被当成一个整体插入
db.users.updateMany({ "username" : "jack"}, { "$addToSet" : { "favorites.movies" : { "$each" : [ "小电影2 " , "小电影3"]}}})
db.users.updateMany({ "username" : "jack"}, { "$addToSet" : { "favorites.movies" : [ "小电影2 " , "小电影3"]}})
删除字符串数组中元素示例
db.users.updateMany({ "username" : "jack"}, { "$pull" : { "favorites.movies" : [ "小电影2 " , "小电影3"]}})
db.users.updateMany({ "username" : "jack"}, { "$pullAll" : { "favorites.movies" : [ "小电影2 " , "小电影3"]}})
向对象数组中插入元素
给jack老师增加一条评论（$push）
db.users.updateOne({"username":"jack"},{"$push":{"comments":{"author":"lison23","content":"ydddyyytttt"}}})
给jack老师批量新增两条评论（$push,$each）
db.users.updateOne({"username":"jack"}, {"$push":{"comments": {"$each":[{"author":"lison22","content":"yyyytttt"}, {"author":"lison23","content":"ydddyyytttt"} ] }}})给jack老师批量新增两条评论并对数组进行排序（$push,$eachm,$sort）
db.users.updateOne({"username":"jack"}, {"$push": {"comments": {"$each":[ {"author":"lison22","content":"yyyytttt"}, {"author":"lison23","content":"ydddyyytttt"} ], $sort: {"author":1} } } })
删除对象数组中元素示
删除lison1对jack的所有评论 （批量删除）
db.users.update({"username":"jack"}, {"$pull":{"comments":{"author":"lison22"}}})
删除lison5对lison评语为“lison是苍老师的小迷弟”的评论
db.users.update({"username":"lison"}, {"$pull":{"comments":{"author":"lison5", "content":"lison是苍老师的小迷弟"}}})
更新对象数组中元素，$符号示例
db.users.updateMany({"username":"jack","comments.author":"lison1"}, {"$set":{"comments.$.content":"xxoo", "comments.$.author":"lison10"} })含义：精确修改某人某一条精确的评论，如果有多个符合条件的数据，则修改最后一条数据。无法批量修改数组元素
更新的原子性
1.mongodb的更新都是原子的，mongodb所有的写操作都是有锁的。mongoDB 2.2之前锁级别为实例级别，mongoDB 2.2以后版本锁级别为数据库级别，mongoDB 3.0中，WiredTiger的锁级别是文档级别；
2.findAndModify命令：在同一往返过程中原子更新文档并返回它；
示例
常规的update的方法不能返回更新后的数据
db.num.update({"_id":ObjectId("5a5b4c285731a2a7cd01c5ae")},{"$inc":{"order":1}})使用findandModify方法在修改数据同时返回更新前的数据或更新后的数据
db.num.findAndModify({ "query":{"_id":ObjectId("5a58cef99506c50abaeb4384")}, "update":{"$inc":{"saleOrder":1}}, "new" : true })3.$isolated命令：mongoDB对写锁进行了优化，对长时间的写操作会为其他的读写操作让路，使用$isolated可以避免这种让路，隔离其他操作，不允许其他操作交叉更新，不能再分片中使用；
例如：db.users.update( {"$isolated”:true}, {"username":"lison"}, {"$pull":{"comments":{"author":"lison5","content":"lison是苍老师的小迷弟"}} })
原生Document代码
@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration("classpath:applicationContext.xml")public class JavaUpdateObjArray { private static final Logger logger = LoggerFactory.getLogger(JavaUpdateObjArray.class); private MongoDatabase db; private MongoCollection<Document> collection; @Resource private MongoClient client; @Before public void init(){ db = client.getDatabase("lison"); collection=db.getCollection("users"); } //--------------------------------------insert demo-------------------------------------------------------------- //给jack老师增加一条评论（$push） //db.users.updateOne({"username":"jack"},// {"$push":{"comments":{"author":"lison23","content":"ydddyyytttt"}}}) @Test public void addOneComment(){ Document comment = new Document().append("author", "lison23") .append("content", "ydddyyytttt"); Bson filter = eq("username","jack"); Bson update = push("comments",comment); UpdateResult updateOne = collection.updateOne(filter, update); System.out.println(updateOne.getModifiedCount()); } // 给jack老师批量新增两条评论（$push,$each）// db.users.updateOne({"username":"jack"}, // {"$push":{"comments":// {"$each":[{"author":"lison33","content":"lison33lison33"},// {"author":"lison44","content":"lison44lison44"}]}}}) @Test public void addManyComment(){ Document comment1 = new Document().append("author", "lison33") .append("content", "lison33lison33"); Document comment2 = new Document().append("author", "lison44") .append("content", "lison44lison44"); Bson filter = eq("username","jack"); Bson pushEach = pushEach("comments",Arrays.asList(comment1,comment2)); UpdateResult updateOne = collection.updateOne(filter, pushEach); System.out.println(updateOne.getModifiedCount()); } // 给jack老师批量新增两条评论并对数组进行排序（$push,$eachm,$sort）// db.users.updateOne({"username":"jack"}, // {"$push": {"comments":// {"$each":[ {"author":"lison22","content":"yyyytttt"},// {"author":"lison23","content":"ydddyyytttt"} ], // $sort: {"author":1} } } }) @Test public void addManySortComment(){ Document comment1 = new Document().append("author", "lison00") .append("content", "lison00lison00"); Document comment2 = new Document().append("author", "lison01") .append("content", "lison01lison01"); Bson filter = eq("username","jack"); Document sortDoc = new Document().append("author", 1); PushOptions pushOption = new PushOptions().sortDocument(sortDoc); Bson pushEach = pushEach("comments",Arrays.asList(comment1,comment2),pushOption); UpdateResult updateOne = collection.updateOne(filter, pushEach); System.out.println(updateOne.getModifiedCount()); } //--------------------------------------delete demo-------------------------------------------------------------- // 删除lison1对jack的所有评论 （批量删除）// db.users.update({"username":“jack"},// {"$pull":{"comments":{"author":"lison23"}}}) @Test public void deleteByAuthorComment(){ Document comment = new Document().append("author", "lison23"); Bson filter = eq("username","jack"); Bson update = pull("comments",comment); UpdateResult updateOne = collection.updateOne(filter, update); System.out.println(updateOne.getModifiedCount()); } // 删除lison5对lison评语为“lison是苍老师的小迷弟”的评论（精确删除）// db.users.update({"username":"lison"},// {"$pull":{"comments":{"author":"lison5",// "content":"lison是苍老师的小迷弟"}}}) @Test public void deleteByAuthorContentComment(){ Document comment = new Document().append("author", "lison5") .append("content", "lison是苍老师的小迷弟"); Bson filter = eq("username","lison"); Bson update = pull("comments",comment); UpdateResult updateOne = collection.updateOne(filter, update); System.out.println(updateOne.getModifiedCount()); } //--------------------------------------update demo--------------------------------------------------------------// db.users.updateMany({"username":"jack","comments.author":"lison1"},// {"$set":{"comments.$.content":"xxoo",// "comments.$.author":"lison10" }})// 含义：精确修改某人某一条精确的评论，如果有多个符合条件的数据，则修改最后一条数据。无法批量修改数组元素 @Test public void updateOneComment(){ Bson filter = and(eq("username","jack"),eq("comments.author","lison01")); Bson updateContent = set("comments.$.content","xxoo"); Bson updateAuthor = set("comments.$.author","lison10"); Bson update = combine(updateContent,updateAuthor); UpdateResult updateOne = collection.updateOne(filter, update); System.out.println(updateOne.getModifiedCount()); } //--------------------------------------findandModify demo--------------------------------------------------------------// 使用findandModify方法在修改数据同时返回更新前的数据或更新后的数据// db.num.findAndModify({// "query":{"_id":ObjectId("5a58cef99506c50abaeb4384")},// "update":{"$inc":{"saleOrder":1}},// "new":true// }) @Test public void findAndModifyTest(){ Bson filter = eq("_id",new ObjectId("5a5a3a87d7598152855d758e")); Bson update = inc("saleOrder",1);// //实例化findAndModify的配置选项 FindOneAndUpdateOptions fauo = new FindOneAndUpdateOptions();// //配置"new":true fauo.returnDocument(ReturnDocument.AFTER);// MongoCollection<Document> numCollection = db.getCollection("myOrder"); Document ret = numCollection.findOneAndUpdate(filter, update,fauo); System.out.println(ret.toJson()); }}Spring实现代码
@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration("classpath:applicationContext.xml")public class SpringUpdateObjArray { private static final Logger logger = LoggerFactory.getLogger(SpringUpdateObjArray.class); @Resource private MongoOperations tempelate; //--------------------------------------insert demo-------------------------------------------------------------- //给jack老师增加一条评论（$push） //db.users.updateOne({"username":"jack"},// {"$push":{"comments":{"author":"lison23","content":"ydddyyytttt"}}}) @Test public void addOneComment(){ Query query = query(Criteria.where("username").is("jack")); Comment comment = new Comment(); comment.setAuthor("lison23"); comment.setContent("ydddyyytttt"); Update push = new Update().push("comments", comment); WriteResult updateFirst = tempelate.updateFirst(query, push, User.class); System.out.println(updateFirst.getN()); } // 给jack老师批量新增两条评论（$push,$each）// db.users.updateOne({"username":"jack"}, // {"$push":{"comments":// {"$each":[{"author":"lison33","content":"lison33lison33"},// {"author":"lison44","content":"lison44lison44"}]}}}) @Test public void addManyComment(){ Query query = query(Criteria.where("username").is("jack")); Comment comment1 = new Comment(); comment1.setAuthor("lison55"); comment1.setContent("lison55lison55"); Comment comment2 = new Comment(); comment2.setAuthor("lison66"); comment2.setContent("lison66lison66"); Update push = new Update().pushAll("comments", new Comment[]{comment1,comment2}); WriteResult updateFirst = tempelate.updateFirst(query, push, User.class); System.out.println(updateFirst.getN()); } // 给jack老师批量新增两条评论并对数组进行排序（$push,$eachm,$sort）// db.users.updateOne({"username":"jack"}, // {"$push": {"comments":// {"$each":[ {"author":"lison22","content":"yyyytttt"},// {"author":"lison23","content":"ydddyyytttt"} ], // $sort: {"author":1} } } }) @Test public void addManySortComment(){ Query query = query(Criteria.where("username").is("jack")); Comment comment1 = new Comment(); comment1.setAuthor("lison77"); comment1.setContent("lison55lison55"); Comment comment2 = new Comment(); comment2.setAuthor("lison88"); comment2.setContent("lison66lison66"); Update update = new Update(); PushOperatorBuilder pob = update.push("comments"); pob.each(comment1,comment2); pob.sort(new Sort(new Sort.Order(Direction.DESC, "author"))); System.out.println("---------------"); WriteResult updateFirst = tempelate.updateFirst(query, update,User.class); System.out.println(updateFirst.getN()); } //--------------------------------------delete demo-------------------------------------------------------------- // 删除lison1对jack的所有评论 （批量删除）// db.users.update({"username":“jack"},// {"$pull":{"comments":{"author":"lison23"}}}) @Test public void deleteByAuthorComment(){ Query query = query(Criteria.where("username").is("jack")); Comment comment1 = new Comment(); comment1.setAuthor("lison55"); Update pull = new Update().pull("comments",comment1); WriteResult updateFirst = tempelate.updateFirst(query, pull, User.class); System.out.println(updateFirst.getN()); } // 删除lison5对lison评语为“lison是苍老师的小迷弟”的评论（精确删除）// db.users.update({"username":"lison"},// {"$pull":{"comments":{"author":"lison5",// "content":"lison是苍老师的小迷弟"}}}) @Test public void deleteByAuthorContentComment(){ Query query = query(Criteria.where("username").is("lison")); Comment comment1 = new Comment(); comment1.setAuthor("lison5"); comment1.setContent("lison是苍老师的小迷弟"); Update pull = new Update().pull("comments",comment1); WriteResult updateFirst = tempelate.updateFirst(query, pull, User.class); System.out.println(updateFirst.getN()); } //--------------------------------------update demo--------------------------------------------------------------// db.users.updateMany({"username":"jack","comments.author":"lison1"},// {"$set":{"comments.$.content":"xxoo",// "comments.$.author":"lison10" }})// 含义：精确修改某人某一条精确的评论，如果有多个符合条件的数据，则修改最后一条数据。无法批量修改数组元素 @Test public void updateOneComment(){ Query query = query(where("username").is("lison").and("comments.author").is("lison4")); Update update = update("comments.$.content","xxoo").set("comments.$.author","lison11"); WriteResult updateFirst = tempelate.updateFirst(query, update, User.class); System.out.println(updateFirst.getN()); }//--------------------------------------findandModify demo--------------------------------------------------------------//使用findandModify方法在修改数据同时返回更新前的数据或更新后的数据//db.num.findAndModify({// "query":{"_id":ObjectId("5a58cef99506c50abaeb4384")},// "update":{"$inc":{"saleOrder":1}},// "new":true// }) @Test public void findAndModifyTest(){ Query query = query(where("_id").is(new ObjectId("5a5a3a87d7598152855d758e"))); Update update = new Update().inc("saleOrder", 1); FindAndModifyOptions famo = FindAndModifyOptions.options().returnNew(true); MyOrder ret = tempelate.findAndModify(query, update,famo, MyOrder.class); System.out.println(ret.getSaleOrder()); } }
