mongodb-文档的插入、更新与删除操作

一、文档的插入

-- 单文档插入
db.COLLECTION_NAME.insert(document)
db.COLLECTION_NAME.insertOne(document)
-- insert也可以插入多文档
db.COLLECTION_NAME.save(document)

-- insert与save区别
-- insert方法插入若文档中已存在该文档，会报错，反之写入
-- save方法插入若集合中已存在该文档，则会更新它，反之写入

-- 多文档插入
db.COLLECTION_NAME.insertMany([document1,document2]...)
-- 使用数组[document],[]

 举例

db.comment.insert(
{"articleid":"100000","content":"今天天气真好,阳光明媚","userid":"1001",
"nickname":"Rose","age":"20","phone":"18807141995","createdatetime":new Date(),
"likenum":NumberInt(10),"state":null}
)
db.comment.insert([
{_id:1,"articleid":"100000","content":"清晨，我们不该把时间浪费在手机上，健康很重要，喝一杯温水，幸福你我他","userid":"1001",
"nickname":"相忘于江湖","age":"20","phone":{"homephone":"0531-88888","mobilephone":"18807141995"},"createdatetime":new Date("2022-3-15 09:09:09"),
"likenum":NumberInt(10),"state":null},
{_id:2,"articleid":"100000","content":"我夏天空腹喝凉开水，冬天喝温开水","userid":"1001",
"nickname":"伊人憔悴","age":"20","phone":{"homephone":"0531-88888","mobilephone":"18807141995"},"createdatetime":new Date("2022-3-15 09:09:09"),
"likenum":NumberInt(10),"state":null},
{_id:3,"articleid":"100000","content":"夏天和冬天我都喝凉开水","userid":"1001",
"nickname":"杰克船长","age":"20","phone":{"homephone":"0531-88888","mobilephone":"18807141995"},"createdatetime":new Date("2022-3-15 09:09:09"),
"likenum":NumberInt(10),"state":null}
 ])

二、文档的删除

-- 删除所有文档
db.COLLECTION_NAME.remove({})
-- 什么条件都没有，删除所有的

-- 删除单个文档
db.COLLECTION_NAME.remove(<query>,{justOne:<boolean>,writeConcern:<document>})

--query参数：可选参数，表示删除文档的条件

--{justOne:<boolean>,writeConcern:<document>}：可选参数，justOne为true时表示查询到多个文档时只删除第一个文档。writeConcern表示抛出异常的级别

举例

db.comment.remove({"nickname":"爱德华"})

三、文档的更新 

db.COLLECTION_NAME.update(criteria,objNew,upsert,multi)