做增删改查操作前都要先切换到需要操作的数据库
db.集合名(Collection).操作(参数) 这个操作是个方法类似于orm操作
新建数据库db1
> use db1
switched to db db1
1.插入:
MongoDB 之 插入数据(insert() insertOne() insertMany()) 之 Collection
insert() :插入一条或者多条数据,需要带有允许插入多条的参数,这个方法目前官方已经不推荐喽
db.user.insert( { id:1,name:"jack",age:73 } )
> db.user.insert( { id:1,name:"jack",age:73 } )
WriteResult({ "nInserted" : 1 })
insertOne(): 插入一条数据,官方推荐,效率更高
> db.user.insertOne( { id:2,name:"mike",age:84 } )
{
"acknowledged" : true,
"insertedId" : ObjectId("5ca78ea8219efd687462f95c")
}
我们可以看出这两张方法返回值不同
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
insertMany():插入多条数据,无需参数控制,官方推荐
插入三条数据
> db.user.insertMany([{ id:3,name:"peter",age:14 },{ id:4,name:"tom",age:13 },{ id:5,name:"ben",age:24 }])
{
"acknowledged" : true,
"insertedIds" : [
ObjectId("5ca79127219efd687462f95d"),
ObjectId("5ca79127219efd687462f95e"),
ObjectId("5ca79127219efd687462f95f")
]
}
验证
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95d"), "id" : 3, "name" : "peter", "age" : 14 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca79127219efd687462f95f"), "id" : 5, "name" : "ben", "age" : 24 }
2.查询
MongoDB 之 查询数据(find findOne) 之 这里没有findMany
find() 无条件查找:将该集合(Collection)中所有的数据一次性返回
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95d"), "id" : 3, "name" : "peter", "age" : 14 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca79127219efd687462f95f"), "id" : 5, "name" : "ben", "age" : 24 }
db.user.find( { name:"jack" } ) 条件查询
返回name="jack"数据,这里会返回多条数据
> db.user.find({name:"jack"})
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
findOne():无条件查找一条数据,默认当前Collection中的第一条数据,只返回一条数据
> db.user.findOne()
{
"_id" : ObjectId("5ca65381bb9b65f40b7e5502"),
"id" : 1,
"name" : "jack",
"age" : 73
}
findOne({age:84}) : 条件查找一条age等于84的数据,如有多条数据则返回更靠前的数据
> db.user.findOne({age:84})
{
"_id" : ObjectId("5ca78ea8219efd687462f95c"),
"id" : 2,
"name" : "mike",
"age" : 84
}
做个测试findOne多条数据,插入多一条age等于84数据,然后再用findOne条件查询
最后返回靠前的数据,并且只返回一条数据
> db.user.insertOne({id:6,name:"Mary",age:84})
{
"acknowledged" : true,
"insertedId" : ObjectId("5ca798eb219efd687462f960")
}
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95d"), "id" : 3, "name" : "peter", "age" : 14 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca79127219efd687462f95f"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca798eb219efd687462f960"), "id" : 6, "name" : "Mary", "age" : 84 }
> db.user.findOne({age:84})
{
"_id" : ObjectId("5ca78ea8219efd687462f95c"),
"id" : 2,
"name" : "mike",
"age" : 84
}
3.删除
MongoDB 之 删除数据(remove)
remove({}):无条件删除数据,这里要注意了,这是删除所有数据,清空整个集合数据Collection
remove({name:"peter"}) : 条件删除name等于"peter"的所有Document
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95d"), "id" : 3, "name" : "peter", "age" : 14 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca79127219efd687462f95f"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca798eb219efd687462f960"), "id" : 6, "name" : "Mary", "age" : 84 }
> db.user.remove({"name":"peter"})
WriteResult({ "nRemoved" : 1 })
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca79127219efd687462f95f"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca798eb219efd687462f960"), "id" : 6, "name" : "Mary", "age" : 84 }
deleteOne(): 传入要删除的那个字段查询条件,删除一条
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca79127219efd687462f95f"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca798eb219efd687462f960"), "id" : 6, "name" : "Mary", "age" : 84 }
> db.user.deleteOne({name:"ben"})
{ "acknowledged" : true, "deletedCount" : 1 }
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca798eb219efd687462f960"), "id" : 6, "name" : "Mary", "age" : 84 }
deleteMany(): 删除多条数据
有两条数据age=84的,利用deleteMany方法删除,把age=84的数据都删除,下面删除了两条数据
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca78ea8219efd687462f95c"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca798eb219efd687462f960"), "id" : 6, "name" : "Mary", "age" : 84 }
> db.user.deleteMany({ age:84 })
{ "acknowledged" : true, "deletedCount" : 2 }
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
drop() 和 remove一样 可以清空整张表
> db.user.find()
{ "_id" : ObjectId("5ca65381bb9b65f40b7e5502"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca79127219efd687462f95e"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca7a0ff219efd687462f961"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a0ff219efd687462f962"), "id" : 3, "name" : "peter", "age" : 14 }
{ "_id" : ObjectId("5ca7a0ff219efd687462f964"), "id" : 6, "name" : "Mary", "age" : 84 }
> db.user.drop()
true
> db.user.find()
4.更新
MongoDB 之 修改数据(update updateOne updateMany) 之 跟insert一样,官方不推荐update的写法
update():
update({"name":"peter"},{$set:{"age":21}}):根据条件修改该条数据的内容
把name等于"peter"中数据的age改为21,
这里要注意的是({"条件"},{"关键字":{"修改内容"}}),其中如果条件为空,那么将会修改Collection中所有的数据
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 14 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84 }
>
> db.user.update( {"name":"peter" }, {$set: {age:21} })
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 21 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84 }
updateOne():
updateOne({"age":13},{$set:{"name":"xiaogang"}}):根据条件修改一条数据的内容,如出现多条,只修改最高前的数据
把age等于13的所有数据中第一条数据的name改为xiaogang
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 21 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "tom", "age" : 13 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84 }
>
>
> db.user.updateOne( {age:13 }, {$set: {"name":"xiaogang"} })
{ "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 1 }
>
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 21 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "xiaogang", "age" : 13 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84 }
查询到指定的字段的数据,更新加一个字段
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 21 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "xiaogang", "age" : 13 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84 }
> db.user.updateOne( {age:13 }, {$set: {hobby:["羽毛球","篮球","足球"]} })
{ "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 1 }
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 21 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "xiaogang", "age" : 13, "hobby" : [ "羽毛球", "篮球", "足球" ] }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84
updateMany():
updateMany({"age":84},{$set:{"gender":"男"}}):根据条件修改所有数据的内容,多条修改
把age等于84的所有数据中新增一个字段gender="男"
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 21 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "xiaogang", "age" : 13, "hobby" : [ "羽毛球", "篮球", "足球" ] }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84 }
> db.user.updateMany( {age:84 }, {$set: {gender:"男"} })
{ "acknowledged" : true, "matchedCount" : 2, "modifiedCount" : 2 }
> db.user.find()
{ "_id" : ObjectId("5ca7a4b0219efd687462f965"), "id" : 1, "name" : "jack", "age" : 73 }
{ "_id" : ObjectId("5ca7a4b7219efd687462f966"), "id" : 2, "name" : "mike", "age" : 84, "gender" : "男" }
{ "_id" : ObjectId("5ca7a4c4219efd687462f967"), "id" : 3, "name" : "peter", "age" : 21 }
{ "_id" : ObjectId("5ca7a4c4219efd687462f968"), "id" : 4, "name" : "xiaogang", "age" : 13, "hobby" : [ "羽毛球", "篮球", "足球" ] }
{ "_id" : ObjectId("5ca7a4c4219efd687462f969"), "id" : 5, "name" : "ben", "age" : 24 }
{ "_id" : ObjectId("5ca7a505219efd687462f96a"), "id" : 6, "name" : "Mary", "age" : 84, "gender" : "男" }
$set:{"gender":"男"} 解释: $set 是update时的关键字,表示我要设置gender属性的值为"男"
如果该条Documents没有gender属性,他就会自动创建一个gender属性并且赋值为"男"
$set是修改器之一 :设置将某key设置为某值