目的
ざっくりとMongoDBを把握したい
ダウンロード
気軽にCentOS6上で試したいのでbinaryをダウンロード。
https://www.mongodb.org/dl/linux/x86_64-rhel62
mongodbのファイル構成
$ tree .
.
├── GNU-AGPL-3.0
├── MPL-2
├── README
├── THIRD-PARTY-NOTICES
└── bin
├── bsondump
├── mongo
├── mongod
├── mongodump
├── mongoexport
├── mongofiles
├── mongoimport
├── mongooplog
├── mongoperf
├── mongorestore
├── mongos
├── mongosniff
├── mongostat
└── mongotop
mongodの起動
$ mkdir -p ./data/db
$ ./bin/mongod -dbpath data/db
MongoDBのデータ構造
データベースはMySQLでいうところのデータベースで、Collectionはテーブル相当でしょうか。Documentは行相当だけどスキーマレスであるところがRDBとは違う。primary keyは"_id"あたり？
MongoDB/
├── Database1
│ ├── Collection1
│ │ ├── Document1
│ │ └── Document2
│ └── Collection2
│ ├── Document1
│ └── Document2
└── Database2
├── Collection1
│ ├── Document1
│ └── Document2
└── Collection2
├── Document1
└── Document2
---------------
> var c = db.col1.find()
> while(c.hasNext())printjson(c.next())
{ "_id" : ObjectId("584396e96516646a4dfeab45"), "name" : "mongo" }
{
"_id" : ObjectId("584397126516646a4dfeab46"),
"string" : "hello",
"array" : [
"sun",
"mon",
"tue"
]
}
{ "_id" : ObjectId("584398486516646a4dfeab47"), "name" : "hogehoge" }
{ "_id" : ObjectId("584399996516646a4dfeab48"), "x" : 4, "j" : 1 }
{ "_id" : ObjectId("584399996516646a4dfeab49"), "x" : 4, "j" : 2 }
{ "_id" : ObjectId("584399996516646a4dfeab4a"), "x" : 4, "j" : 3 }
クライアントで接続
$ ./bin/mongo
> help
db.help() help on db methods
db.mycoll.help() help on collection methods
sh.help() sharding helpers
rs.help() replica set helpers
help admin administrative help
help connect connecting to a db help
help keys key shortcuts
help misc misc things to know
help mr mapreduce
show dbs show database names
show collections show collections in current database
show users show users in current database
show profile show most recent system.profile entries with time >= 1ms
show logs show the accessible logger names
show log [name] prints out the last segment of log in memory, 'global' is default
use <db_name> set current database
db.foo.find() list objects in collection foo
db.foo.find( { a : 1 } ) list objects in foo where a == 1
it result of the last line evaluated; use to further iterate
DBQuery.shellBatchSize = x set default number of items to display on shell
exit quit the mongo shell
コマンド
clientで接続
mongo [serverアドレス]/[DB名]
$ ./bin/mongo localhost/testdb
MongoDB shell version: 3.2.11
connecting to: localhost/testdb
DB操作
DB切り替え・作成
$ use [DB名]
DB削除
$ use [DB名]
db.dropDatabase()
{ "ok" : 1 }
DB一覧
$ show dbs
Collection操作
MySQLでいうところのテーブルか。
一覧
use [DB名]
show collections
コレクション作成
use [DB名]
db.createCollection("col1")
{ "ok" : 1 }
コレクション削除
use [DB名]
db.col1.drop()
TAB補完
便利。
db.drop
db.dropAllRoles( db.dropAllUsers( db.dropDatabase( db.dropRole( db.dropUser(
"not master and slaveOk=false"が出たとき
db.getMongo().setSlaveOk()