4，mongodb的入門命令
1: mongo入門命令
show dbs 檢視當前的資料庫
use databaseName 選庫
show tables/collections 檢視當前庫下的collection
2， 建立庫，建立表，再插入資料
> show dbs;
local 0.078GB
> use shop
switched to db shop
> show dbs;
local 0.078GB
> show collections;
> db.user.insert({name:'lili',age:22});
WriteResult({ "nInserted" : 1 })
> db.user.find();
{ "_id" : ObjectId("5aeeb40d1ca0f3732696f5d3"), "name" : "lili", "age" : 22 }
> show collections;
system.indexes
user
>
3，自定義ID 插入資料
> db.user.insert({_id:2,name:'xiaoming',hobby:['football','basketball'],intro:{title:'wenzhang',local:'beijing'}});
WriteResult({ "nInserted" : 1 })
> db.user.find();
{ "_id" : ObjectId("5aeeb40d1ca0f3732696f5d3"), "name" : "lili", "age" : 22 }
{ "_id" : 2, "name" : "xiaoming", "hobby" : [ "football", "basketball" ], "intro" : { "title" : "wenzhang", "local" : "beijing" } }
>
4，刪除文件（即表）
> db.goods.insert({name:'lili'});
WriteResult({ "nInserted" : 1 })
> show collections;
goods
system.indexes
> show dbs;
admin 0.078GB
local 0.078GB
> db
admin
> db.goods.drop();
true
> show collections;
system.indexes
>
5,刪除資料庫
> show dbs;
admin 0.078GB
local 0.078GB
> db.dropDatabase()
{ "dropped" : "admin", "ok" : 1 }
> db
admin
> show dbs;
local 0.078GB
>
6，增加單篇文件
> db.stu.insert({sn:'001',name:'xiaoming'});
WriteResult({ "nInserted" : 1 })
> db.stu.find();
{ "_id" : ObjectId("5aeeb6251ca0f3732696f5d4"), "sn" : "001", "name" : "xiaoming" }
>
7，增加多個文件（沒有指定ID，系統會使用預設的隨機ID）
> db.stu.insert([{_id:3,name:'zhangfei'},{sn:'004',name:'guanyu'},{sn:005,name:'liubei'}]);
BulkWriteResult({
"writeErrors" : [ ],
"writeConcernErrors" : [ ],
"nInserted" : 3,
"nUpserted" : 0,
"nMatched" : 0,
"nModified" : 0,
"nRemoved" : 0,
"upserted" : [ ]
})
> db.stu.find();
{ "_id" : ObjectId("5aeeb6251ca0f3732696f5d4"), "sn" : "001", "name" : "xiaoming" }
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "guanyu" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "sn" : 5, "name" : "liubei" }
>
8，刪除指定的行，（如果不寫條件刪除，會刪除所有的行）
> db.stu.find();
{ "_id" : ObjectId("5aeeb6251ca0f3732696f5d4"), "sn" : "001", "name" : "xiaoming" }
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "guanyu" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "sn" : 5, "name" : "liubei" }
>
>
> db.stu.remove({sn:'001'});
WriteResult({ "nRemoved" : 1 })
> db.stu.find();
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "guanyu" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "sn" : 5, "name" : "liubei" }
>
9，刪除stu表中gender屬性為m的文件,只刪除1行.
db.stu.remove({gender:’m’,true});
10，改操作
結果: 文件中的其他列也不見了,改後只有_id和name列了.
即--新文件直接替換了舊文件,而不是修改
> db.stu.find();
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "guanyu" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "sn" : 5, "name" : "liubei" }
> db.stu.update({name:'liubei'},{'name':'liubei ta de son'})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.stu.find();
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "guanyu" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "name" : "liubei ta de son" }
>
如果是想修改文件的某列,可以用$set關鍵字：
> db.stu.find();
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "guanyu" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "name" : "liubei ta de son" }
>
> db.stu.update({sn:'004'},{$set:{name:'QQ'}});
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.stu.find();
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "QQ" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "name" : "liubei ta de son" }
>
11，
修改時的賦值表示式
$set 修改某列的值
$unset 刪除某個列
$rename 重新命名某個列
$inc 增長某個列
> db.stu.find();
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "QQ" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "name" : "liubei ta de son" }
{ "_id" : ObjectId("5aeec01e1ca0f3732696f5d7"), "name" : "wukong", "jinggu" : "true", "sex" : "m", "age" : 500 }
>
>db.stu.update({name:'wukong'},{$set:{name:'dzsf'},$unset:{jinggu:1},$rename:{sex:'gender'},$inc:{age:1}});
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.stu.find();
{ "_id" : 3, "name" : "zhangfei" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d5"), "sn" : "004", "name" : "QQ" }
{ "_id" : ObjectId("5aeeb7721ca0f3732696f5d6"), "name" : "liubei ta de son" }
{ "_id" : ObjectId("5aeec01e1ca0f3732696f5d7"), "name" : "dzsf", "age" : 501, "gender" : "m" }
>
12，
db.news.update({age:21},{$set:{age:22}},{multi:true});
multi的意思是把news中所有age=21的文件,都修改（不設定multi預設只會修改一行）
db.news.update({_id:99},{x:123,y:234},{upsert:true});
如果沒有_id=99的文件被修改,就直接插入該文件
13，這裡的空的{} 表示查詢所有的行。gender:1 表示只查這一列。
14，
例1:db.stu.find()
查詢所有文件 所有內容
例2: db.stu.find({},{gendre:1})
查詢所有文件,的gender屬性 (_id屬性預設總是查出來)
例3: db.stu.find({},{gender:1, _id:0})
查詢所有文件的gender屬性,且不查詢_id屬性
例3: db.stu.find({gender:’male’},{name:1,_id:0});
查詢所有gender屬性值為male的文件中的name屬性
15，基礎查詢 where的練習:
15-1主鍵為32的商品
db.goods.find({goods_id:32});
15-2不屬第3欄目的所有商品($ne)
db.goods.find({cat_id:{$ne:3}},{goods_id:1,cat_id:1,goods_name:1});
15-3本店價格高於3000元的商品{$gt}
db.goods.find({shop_price:{$gt:3000}},{goods_name:1,shop_price:1});
15-4本店價格低於或等於100元的商品($lte)
db.goods.find({shop_price:{$lte:100}},{goods_name:1,shop_price:1});
15-5取出第4欄目或第11欄目的商品($in)
db.goods.find({cat_id:{$in:[4,11]}},{goods_name:1,shop_price:1});
15-6取出100<=價格<=500的商品($and)
db.goods.find({$and:[{price:{$gt:100},{$price:{$lt:500}}}]);
15-7取出不屬於第3欄目且不屬於第11欄目的商品($and $nin和$nor分別實現)
db.goods.find({$and:[{cat_id:{$ne:3}},{cat_id:{$ne:11}}]},{goods_name:1,cat_id:1})
db.goods.find({cat_id:{$nin:[3,11]}},{goods_name:1,cat_id:1});
db.goods.find({$nor:[{cat_id:3},{cat_id:11}]},{goods_name:1,cat_id:1});
15-8取出價格大於100且小於300,或者大於4000且小於5000的商品()
db.goods.find({$or:[{$and:[{shop_price:{$gt:100}},{shop_price:{$lt:300}}]},{$and:[{shop_price:{$gt:4000}},{shop_price:{$lt:5000}}]}]},{goods_name:1,shop_price:1});
15-9取出goods_id%5 == 1, 即,1,6,11,..這樣的商品
db.goods.find({goods_id:{$mod:[5,1]}});
15-10取出有age屬性的文件
db.stu.find({age:{$exists:1}});
15-11含有age屬性的文件將會被查出
16，
