目次
とある日
MongoDBを触ってみたいと思ったので試しに検証しました際に、RDBと比べて違った点があったのでまとめます。
チュートリアル
構築
↓こちらの記事を参考にDocker-composeで構築しました。
docker-composeでmongoDB環境を構築して使う - Qiita
# Use root/example as user/password credentials version: '3.1' services: mongo: image: mongo restart: always environment: MONGO_INITDB_ROOT_USERNAME: root MONGO_INITDB_ROOT_PASSWORD: password mongo-express: image: mongo-express restart: always ports: - 8081:8081 environment: ME_CONFIG_MONGODB_ADMINUSERNAME: root ME_CONFIG_MONGODB_ADMINPASSWORD: password ME_CONFIG_MONGODB_URL: mongodb://root:example@mongo:27017/
mongo-expressはGUIのやつなので（phpmyadminみたいな）いらないかなと後で思いました。
Dockerのimageが公式で用意されているので簡単に構築できます。
接続
C:\Users\Documents\GitHub\Docker\Docker-compose\MongoDB>docker-compose up -d [+] Running 20/20 - mongo-express Pulled 16.4s - 6a428f9f83b0 Pull complete 4.9s - f2b1fb32259e Pull complete 8.7s - 40888f2a0a1f Pull complete 8.9s - 4e3cc9ce09be Pull complete 8.9s - eaa1898f3899 Pull complete 9.1s - ab4078090382 Pull complete 11.0s - ae780a42c79e Pull complete 11.1s - e60224d64a04 Pull complete 11.2s - mongo Pulled 24.7s - 7b1a6ab2e44d Pull complete 4.1s - 90eb44ebc60b Pull complete 4.2s - 5085b59f2efb Pull complete 4.5s - c7499923d022 Pull complete 4.9s - 019496b6c44a Pull complete 5.0s - c0df4f407f69 Pull complete 5.1s - 351daa315b6c Pull complete 5.1s - a233e6240acc Pull complete 19.5s - a3f57d6be64f Pull complete 19.5s - dd1b5b345323 Pull complete 19.6s [+] Running 3/3 - Network mongodb_default Created 0.1s - Container mongodb_mongo_1 Started 0.7s - Container mongodb_mongo-express_1 Started 0.8s C:\Users\Documents\GitHub\Docker\Docker-compose\MongoDB>docker-compose ps NAME COMMAND SERVICE STATUS PORTS mongodb_mongo-express_1 "tini -- /docker-ent…" mongo-express restarting mongodb_mongo_1 "docker-entrypoint.s…" mongo running 27017/tcp C:\Users\Documents\GitHub\Docker\Docker-compose\MongoDB>docker-compose exec mongo bash root@ae2f058f0f67:/# ll total 172 drwxr-xr-x 1 root root 4096 Dec 27 21:53 ./ drwxr-xr-x 1 root root 4096 Dec 27 21:53 ../ -rwxr-xr-x 1 root root 0 Dec 27 21:53 .dockerenv* lrwxrwxrwx 1 root root 7 Oct 6 16:47 bin -> usr/bin/ drwxr-xr-x 2 root root 4096 Apr 15 2020 boot/ drwxr-xr-x 4 root root 4096 Dec 8 00:25 data/ drwxr-xr-x 5 root root 340 Dec 27 21:53 dev/ drwxr-xr-x 2 root root 4096 Oct 16 03:04 docker-entrypoint-initdb.d/ drwxr-xr-x 1 root root 4096 Dec 27 21:53 etc/ drwxr-xr-x 2 root root 4096 Apr 15 2020 home/ -rw-r--r-- 1 root root 108975 Oct 16 03:04 js-yaml.js lrwxrwxrwx 1 root root 7 Oct 6 16:47 lib -> usr/lib/ lrwxrwxrwx 1 root root 9 Oct 6 16:47 lib32 -> usr/lib32/ lrwxrwxrwx 1 root root 9 Oct 6 16:47 lib64 -> usr/lib64/ lrwxrwxrwx 1 root root 10 Oct 6 16:47 libx32 -> usr/libx32/ drwxr-xr-x 2 root root 4096 Oct 6 16:47 media/ drwxr-xr-x 2 root root 4096 Oct 6 16:47 mnt/ drwxr-xr-x 2 root root 4096 Oct 6 16:47 opt/ dr-xr-xr-x 320 root root 0 Dec 27 21:53 proc/ drwx------ 1 root root 4096 Oct 16 03:04 root/ drwxr-xr-x 5 root root 4096 Oct 6 16:58 run/ lrwxrwxrwx 1 root root 8 Oct 6 16:47 sbin -> usr/sbin/ drwxr-xr-x 2 root root 4096 Oct 6 16:47 srv/ dr-xr-xr-x 11 root root 0 Dec 27 21:53 sys/ drwxrwxrwt 1 root root 4096 Dec 27 21:53 tmp/ drwxr-xr-x 1 root root 4096 Dec 8 00:24 usr/ drwxr-xr-x 1 root root 4096 Oct 6 16:58 var/ root@ae2f058f0f67:/# root@ae2f058f0f67:/# mongo admin -u root -p MongoDB shell version v5.0.5 Enter password: connecting to: mongodb://127.0.0.1:27017/admin?compressors=disabled&gssapiServiceName=mongodb Implicit session: session { "id" : UUID("65ed13ad-a7d8-4eae-aebb-f9c5a3717090") } MongoDB server version: 5.0.5 ================ Warning: the "mongo" shell has been superseded by "mongosh", which delivers improved usability and compatibility.The "mongo" shell has been deprecated and will be removed in an upcoming release. For installation instructions, see https://docs.mongodb.com/mongodb-shell/install/ ================ Welcome to the MongoDB shell. For interactive help, type "help". For more comprehensive documentation, see https://docs.mongodb.com/ Questions? Try the MongoDB Developer Community Forums https://community.mongodb.com --- The server generated these startup warnings when booting: 2021-12-27T21:53:04.025+00:00: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem 2021-12-27T21:53:05.284+00:00: /sys/kernel/mm/transparent_hugepage/enabled is 'always'. We suggest setting it to 'never' --- --- Enable MongoDB's free cloud-based monitoring service, which will then receive and display metrics about your deployment (disk utilization, CPU, operation statistics, etc). The monitoring data will be available on a MongoDB website with a unique URL accessible to you and anyone you share the URL with. MongoDB may use this information to make product improvements and to suggest MongoDB products and deployment options to you. To enable free monitoring, run the following command: db.enableFreeMonitoring() To permanently disable this reminder, run the following command: db.disableFreeMonitoring() --- > show databases admin 0.000GB config 0.000GB local 0.000GB
データ挿入
> use test2 switched to db test2 > db.hoge.insert({ name: "test" }) WriteResult({ "nInserted" : 1 }) > db.hoge.find() { "_id" : ObjectId("61ca36c635b01c7a00ba15ce"), "name" : "test" } > db test2 > db.people.insertOne( { ... user_id: "abc123", ... age: 55, ... status: "A" ... } ) { "acknowledged" : true, "insertedId" : ObjectId("61ca37f735b01c7a00ba15cf") } > db.hoge.find() { "_id" : ObjectId("61ca36c635b01c7a00ba15ce"), "name" : "test" } > db.people.find() { "_id" : ObjectId("61ca37f735b01c7a00ba15cf"), "user_id" : "abc123", "age" : 55, "status" : "A" } > db test2 > table uncaught exception: ReferenceError: table is not defined : @(shell):1:1 > show collections; hoge people > db.createCollection('test'); { "ok" : 1 } > show collections; hoge people test > db.test.find() > db.tst.find() > db.system.users.find(); > > db.system.users.find(); > use admin switched to db admin > db.system.users.find(); { "_id" : "admin.root", "userId" : UUID("cae1fa15-67cc-4e42-b17a-84eae27d923e"), "user" : "root", "db" : "admin", "credentials" : { "SCRAM-SHA-1" : { "iterationCount" : 10000, "salt" : "wdpPednmfmpH/3PpafI1Qg==", "storedKey" : "ILk3afygYIYTP/n7UMipZ4ExhD4=", "serverKey" : "9+CNpNgfLmQhCE49ZK3MwXoaG4w=" }, "SCRAM-SHA-256" : { "iterationCount" : 15000, "salt" : "XeA8Xk9A4CXgHPj+kDcMswaVx1a8HSLnM0I3fQ==", "storedKey" : "ZJ9vl+pM9yZq1J3zTONN/TyZ1EXTkztBR2ny5nSHdIM=", "serverKey" : "XUytDm5LQwNO9po0amT671sOLyRjsXocvrNoqov3VvQ=" } }, "roles" : [ { "role" : "root", "db" : "admin" } ] } >
RDBとの操作的違い
用語
RDBはテーブルと言うがNoSQLとかはコネクションっていうらしい。
SQL to MongoDB Mapping Chart — MongoDB Manual
| SQL Terms/Concepts | MongoDB Terms/Concepts |
|---|---|
| database | database |
| table | collection |
| row | document or BSON document |
| column | field |
| index | index |
コネクションとテーブルの振る舞い
ないコネクションにfindした際、データがない場合とコネクションがない場合の結果が同じで、コネクション名のミスに気づかなそうだなと。
> show collections; hoge people test > db.test.find() > db.tst.find()
オペレーションの作成
作成または挿入操作は、コレクションに新しいドキュメントを追加します。コレクションが現在存在しない場合、挿入操作によってコレクションが作成されます。
それの原因は、生成されるタイミングが違うかららしい。
CUIの振る舞い
MySQLとかのRDBMSだとコロン打つまで入力が続くが、MongoDBだとそこらへんよしなに判断してくれるみたい。これは便利。
> db.hoge.insert({ name: "test" } ... ) WriteResult({ "nInserted" : 1 })
補完も効くので便利だなと思いました。
> db DBCommandCursor( DBExplainQuery( DBPointer( db > db. Display all 102 possibilities? (y or n) db.adminCommand( db.getMongo( db.printShardingStatus( db.aggregate( db.getName( db.printSlaveReplicationInfo( db.auth( db.getProfilingLevel( db.propertyIsEnumerable db.changeUserPassword( db.getProfilingStatus( db.prototype db.commandHelp( db.getQueryOptions( db.removeUser( db.constructor db.getReplicationInfo( db.revokePrivilegesFromRole( db.createCollection( db.getRole( db.revokeRolesFromRole( db.createRole( db.getRoles( db.revokeRolesFromUser( db.createUser( db.getSecondaryOk( db.rotateCertificates( db.createView( db.getSession( db.runCommand( db.currentOP( db.getSiblingDB( db.runCommandWithMetadata( db.currentOp( db.getSisterDB( db.runReadCommand( db.currentOpCursor( db.getSlaveOk( db.serverBits( db.currentOpLegacy( db.getUser( db.serverBuildInfo( db.dbEval( db.getUsers( db.serverCmdLineOpts( db.disableFreeMonitoring( db.getWriteConcern( db.serverStatus( db.dropAllRoles( db.grantPrivilegesToRole( db.setLogLevel( db.dropAllUsers( db.grantRolesToRole( db.setProfilingLevel( db.dropDatabase( db.grantRolesToUser( db.setSecondaryOk( db.dropRole( db.groupeval( db.setSlaveOk( db.dropUser( db.hasOwnProperty db.setWriteConcern( db.enableFreeMonitoring( db.hello( db.shutdownServer( db.eval( db.help( db.stats( db.forceError( db.hoge db.system.users db.fsyncLock( db.hostInfo( db.system.version db.fsyncUnlock( db.isMaster( db.toLocaleString db.getCollection( db.killOP( db.toString( db.getCollectionInfos( db.killOp( db.tojson( db.getCollectionNames( db.listCommands( db.unsetWriteConcern( db.getFreeMonitoringStatus( db.loadServerScripts( db.updateRole( db.getLastError( db.logout( db.updateUser( db.getLastErrorCmd( db.printCollectionStats( db.valueOf( db.getLastErrorObj( db.printReplicationInfo( db.version( db.getLogComponents( db.printSecondaryReplicationInfo( db.watch( > db.
〆
MongoDBを使ってなにか開発をしてみたいなと思いましたね。
ただ、RDBと違ってかなり自由なので考え方とかが違う点が多々あるので最初は戸惑いそうです。
