awsで在庫管理Webアプリを作ろうと、rdsやauroraを使おうとしたら料金が高すぎる。dynamodbでは検索できない。mongodbが最適？

mongodb入門。windowsにサーバとmongosh(CLIクライント)をインストール。CRUD操作をしてみる。SQL文と違って、コマンドというか関数っぽい感じなのね。

mongodb入門。windowsにサーバとmongosh(CLIクライント)をインストール。CRUD操作をしてみる。SQL文と違って、コマンドというか関数っぽい感じなのね。

とりあえず、まず何をすればいいんだ？
windowsにmongodbサーバをインストールしてみよう。
https://www.mongodb.com/try/download/community

mongoshというコマンドラインツールを使う。
https://www.mongodb.com/docs/mongodb-shell/

mongodbのインストール先にmongoshを配置、環境変数の設定もする
C:\Program Files\MongoDB\Server\7.0\bin\mongosh.exe

mongosh　というコマンドだけでローカルmongodbサーバに接続に行く(mongodb://localhost:27017/)

mongosh
Current Mongosh Log ID: 662af818755826876b46b798
Connecting to:          mongodb://127.0.0.1:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+2.2.5
Using MongoDB:          7.0.8
Using Mongosh:          2.2.5

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

------
   The server generated these startup warnings when booting
   2024-04-25T17:40:24.910+09:00: Access control is not enabled for the database. Read and write access to data and configuration is unrestricted
------

mongosh

Current Mongosh Log ID: 662af818755826876b46b798

Connecting to: mongodb://127.0.0.1:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+2.2.5

Using MongoDB: 7.0.8

Using Mongosh: 2.2.5

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

------

The server generated these startup warnings when booting

2024-04-25T17:40:24.910+09:00: Access control is not enabled for the database. Read and write access to data and configuration is unrestricted

------

# どんなデータベースがあるか？最初から３つあるっぽい。
show dbs
admin    40.00 KiB
config   72.00 KiB
local    40.00 KiB

# DB作成はuse DB名で自動生成される
use myDB

# コレクション（テーブル）も同じく自動生成
myDB> db.createCollection("persons")
{ ok: 1 }
myDB> show collections
persons

# INSERTでレコード(ドキュメント)生成。
db.persons.insert({
name : "adam" ,
age : 25
})
DeprecationWarning: Collection.insert() is deprecated. Use insertOne, insertMany, or bulkWrite.
{
  acknowledged: true,
  insertedIds: { '0': ObjectId('662afabf755826876b46b799') }
}

# 非推奨のinsertを使うな！というのでinsertOneを使う
db.getCollection('persons').insertOne({
  name: 'bell',
  age: 20,

})
{
  acknowledged: true,
  insertedId: ObjectId('662afbb6755826876b46b79a')
}
# getCollection無しでも行けた。
db.persons.insertOne({
  name: 'cecil',
  age: 15,
})
{
  acknowledged: true,
  insertedId: ObjectId('662afc4b755826876b46b79b')
}
# 複数挿入のinsertMany
db.persons.insertMany([
  {
    name: 'adam',
    age: 25
  },
  {
    name: 'david',
    age: 35
  }
])
{
  acknowledged: true,
  insertedIds: {
    '0': ObjectId('662afdaa755826876b46b79c'),
    '1': ObjectId('662afdaa755826876b46b79d')
  }
}

# bulkWriteは、異なる種類の操作（挿入、更新、削除）を一括操作できるらしい。トランザクション？
db.collection.bulkWrite([
  { insertOne: { document: { item: "journal", qty: 25 } } },
  { updateOne: {
    filter: { item: "notebook" },
    update: { $set: { qty: 60 } }
  }},
  { deleteOne: {
    filter: { item: "paper" }
  }}
]);



# select文
myDB> db.persons.find()
[
  { _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },
  { _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil', age: 15 },
  { _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },
  { _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }
]

# WHERE文
db.persons.find( {name:'adam'} )
[
  { _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 }
]

myDB> db.persons.find({age:{$gte:20}})
[
  { _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },
  { _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },
  { _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }
]
myDB> db.persons.find({age:{$gt:20}})
[
  { _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },
  { _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }
]

# OR条件
myDB> db.persons.find({$or:[ {age:20}, {age:35} ]})
[
  { _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },
  { _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }
]

# SELECT name 
db.persons.find({}, {name:1})
[
  { _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell' },
  { _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil' },
  { _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam' },
  { _id: ObjectId('662afdaa755826876b46b79d'), name: 'david' }
]

# ORDER BY 昇順なら1　降順なら-1
db.persons.find().sort({ age: 1 })
[
  { _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil', age: 15 },
  { _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },
  { _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },
  { _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }
]

# 急にsexフィールドを追加
db.persons.insertOne({
  name: 'edy',
  age: 55,
  sex: 'male'
})
{
  acknowledged: true,
  insertedId: ObjectId('662b0299755826876b46b79f')
}

db.persons.find().sort({ age: 1 })
[
  { _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil', age: 15 },
  { _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },
  { _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },
  { _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 },
  {
    _id: ObjectId('662b0299755826876b46b79f'),
    name: 'edy',
    age: 55,
    sex: 'male'
  }
]
# 特定フィールドが存在するドキュメントだけ抽出。これはmysqlに無いね！
db.persons.find({ sex:{$exists:true} }, {_id:0})
[ { name: 'edy', age: 55, sex: 'male' } ]

# count(*)
myDB>  db.persons.countDocuments()
4

# UPDATE文。最初がWHERE条件で、第二引数がSET
db.persons.updateOne(
  { name: "adam" },
  { $set: { age: 30 } }
)
{
  acknowledged: true,
  insertedId: null,
  matchedCount: 1,
  modifiedCount: 1,
  upsertedCount: 0
}

# DELETE文
db.persons.deleteOne({ name: "adam" })
{ acknowledged: true, deletedCount: 1 }

# drop table
db.persons.drop()

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# どんなデータベースがあるか？最初から３つあるっぽい。

show dbs

admin 40.00 KiB

config 72.00 KiB

local 40.00 KiB

# DB作成はuse DB名で自動生成される

use myDB

# コレクション（テーブル）も同じく自動生成

myDB> db.createCollection("persons")

{ ok: 1 }

myDB> show collections

persons

# INSERTでレコード(ドキュメント)生成。

db.persons.insert({

name : "adam" ,

age : 25

})

DeprecationWarning: Collection.insert() is deprecated. Use insertOne, insertMany, or bulkWrite.

{

acknowledged: true,

insertedIds: { '0': ObjectId('662afabf755826876b46b799') }

}

# 非推奨のinsertを使うな！というのでinsertOneを使う

db.getCollection('persons').insertOne({

age: 20,

})

{

acknowledged: true,

insertedId: ObjectId('662afbb6755826876b46b79a')

}

# getCollection無しでも行けた。

db.persons.insertOne({

age: 15,

})

{

acknowledged: true,

insertedId: ObjectId('662afc4b755826876b46b79b')

}

# 複数挿入のinsertMany

db.persons.insertMany([

{

age: 25

{

age: 35

}

])

{

acknowledged: true,

insertedIds: {

'0': ObjectId('662afdaa755826876b46b79c'),

'1': ObjectId('662afdaa755826876b46b79d')

}

# bulkWriteは、異なる種類の操作（挿入、更新、削除）を一括操作できるらしい。トランザクション？

db.collection.bulkWrite([

{ insertOne: { document: { item: "journal", qty: 25 } } },

{ updateOne: {

filter: { item: "notebook" },

update: { $set: { qty: 60 } }

}},

{ deleteOne: {

filter: { item: "paper" }

}}

]);

# select文

myDB> db.persons.find()

[

{ _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },

{ _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil', age: 15 },

{ _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },

{ _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }

]

# WHERE文

db.persons.find( {name:'adam'} )

[

{ _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 }

]

myDB> db.persons.find({age:{$gte:20}})

[

{ _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },

{ _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },

{ _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }

]

myDB> db.persons.find({age:{$gt:20}})

[

{ _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },

{ _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }

]

# OR条件

myDB> db.persons.find({$or:[ {age:20}, {age:35} ]})

[

{ _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },

{ _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }

]

# SELECT name

db.persons.find({}, {name:1})

[

{ _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell' },

{ _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil' },

{ _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam' },

{ _id: ObjectId('662afdaa755826876b46b79d'), name: 'david' }

]

# ORDER BY 昇順なら1　降順なら-1

db.persons.find().sort({ age: 1 })

[

{ _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil', age: 15 },

{ _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },

{ _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },

{ _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 }

]

# 急にsexフィールドを追加

db.persons.insertOne({

age: 55,

sex: 'male'

})

{

acknowledged: true,

insertedId: ObjectId('662b0299755826876b46b79f')

}

db.persons.find().sort({ age: 1 })

[

{ _id: ObjectId('662afc4b755826876b46b79b'), name: 'cecil', age: 15 },

{ _id: ObjectId('662afbb6755826876b46b79a'), name: 'bell', age: 20 },

{ _id: ObjectId('662afdaa755826876b46b79c'), name: 'adam', age: 25 },

{ _id: ObjectId('662afdaa755826876b46b79d'), name: 'david', age: 35 },

{

_id: ObjectId('662b0299755826876b46b79f'),

age: 55,

sex: 'male'

}

]

# 特定フィールドが存在するドキュメントだけ抽出。これはmysqlに無いね！

db.persons.find({ sex:{$exists:true} }, {_id:0})

[ { name: 'edy', age: 55, sex: 'male' } ]

# count(*)

myDB> db.persons.countDocuments()

# UPDATE文。最初がWHERE条件で、第二引数がSET

db.persons.updateOne(

{ name: "adam" },

{ $set: { age: 30 } }

)

{

acknowledged: true,

insertedId: null,

matchedCount: 1,

modifiedCount: 1,

upsertedCount: 0

}

# DELETE文

db.persons.deleteOne({ name: "adam" })

{ acknowledged: true, deletedCount: 1 }

# drop table

db.persons.drop()

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