CouchDBをいじってみる

インストールと起動

$ sudo port install couchdb
$ sudo couchdb
Apache CouchDB 0.9.0 (LogLevel=info) is starting.
Apache CouchDB has started. Time to relax.

curlでアクセスしてみる

$ curl -v http://localhost:5984
* About to connect() to localhost port 5984 (#0)
*   Trying 127.0.0.1... connected
* Connected to localhost (127.0.0.1) port 5984 (#0)
> GET / HTTP/1.1
> User-Agent: curl/7.19.5 (i386-apple-darwin9.6.0) libcurl/7.19.5 zlib/1.2.3
> Host: localhost:5984
> Accept: */*
> 
< HTTP/1.1 200 OK
< Server: CouchDB/0.9.0 (Erlang OTP/R13B)
< Date: Thu, 04 Jun 2009 13:10:27 GMT
< Content-Type: text/plain;charset=utf-8
< Content-Length: 40
< Cache-Control: must-revalidate
< 
{"couchdb":"Welcome","version":"0.9.0"}
* Connection #0 to host localhost left intact
* Closing connection #0

ブラウザで　http://localhost:5984/_utils/index.html　にアクセスしてみる

ブラウザでデータをいれたりしてみる。

curlでデータをいれたりしてみる。

DB作成

$ curl -v -X PUT http://localhost:5984/example
* About to connect() to localhost port 5984 (#0)
*   Trying 127.0.0.1... connected
* Connected to localhost (127.0.0.1) port 5984 (#0)
> PUT /example HTTP/1.1
> User-Agent: curl/7.19.5 (i386-apple-darwin9.6.0) libcurl/7.19.5 zlib/1.2.3
> Host: localhost:5984
> Accept: */*
> 
< HTTP/1.1 201 Created
< Server: CouchDB/0.9.0 (Erlang OTP/R13B)
< Date: Thu, 04 Jun 2009 13:26:13 GMT
< Content-Type: text/plain;charset=utf-8
< Content-Length: 12
< Cache-Control: must-revalidate
< 
{"ok":true}
* Connection #0 to host localhost left intact
* Closing connection #0

PUTでデータ挿入

$ curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"jiro\", \"age\":\"33\"}" http://localhost:5984/example/testdoc
* About to connect() to localhost port 5984 (#0)
*   Trying 127.0.0.1... connected
* Connected to localhost (127.0.0.1) port 5984 (#0)
> PUT /example/testdoc HTTP/1.1
> User-Agent: curl/7.19.5 (i386-apple-darwin9.6.0) libcurl/7.19.5 zlib/1.2.3
> Host: localhost:5984
> Accept: */*
> Content-Type: application/json
> Content-Length: 27
> 
< HTTP/1.1 201 Created
< Server: CouchDB/0.9.0 (Erlang OTP/R13B)
< Etag: "1-2398975676"
< Date: Thu, 04 Jun 2009 13:28:07 GMT
< Content-Type: text/plain;charset=utf-8
< Content-Length: 48
< Cache-Control: must-revalidate
< 
{"ok":true,"id":"testdoc","rev":"1-2398975676"}
* Connection #0 to host localhost left intact
* Closing connection #0

GETで挿入したデータの取得

$ curl -v -X GET http://localhost:5984/example/testdoc
* About to connect() to localhost port 5984 (#0)
*   Trying 127.0.0.1... connected
* Connected to localhost (127.0.0.1) port 5984 (#0)
> GET /example/testdoc HTTP/1.1
> User-Agent: curl/7.19.5 (i386-apple-darwin9.6.0) libcurl/7.19.5 zlib/1.2.3
> Host: localhost:5984
> Accept: */*
> 
< HTTP/1.1 200 OK
< Server: CouchDB/0.9.0 (Erlang OTP/R13B)
< Etag: "1-2398975676"
< Date: Thu, 04 Jun 2009 13:29:07 GMT
< Content-Type: text/plain;charset=utf-8
< Content-Length: 65
< Cache-Control: must-revalidate
< 
{"_id":"testdoc","_rev":"1-2398975676","name":"jiro","age":"33"}
* Connection #0 to host localhost left intact
* Closing connection #0

ブラウザでデータを見るとこんな感じ

DELETEでデータの削除

$ curl -v -X DELETE http://localhost:5984/example/testdoc?rev=1-2398975676
* About to connect() to localhost port 5984 (#0)
*   Trying 127.0.0.1... connected
* Connected to localhost (127.0.0.1) port 5984 (#0)
> DELETE /example/testdoc?rev=1-2398975676 HTTP/1.1
> User-Agent: curl/7.19.5 (i386-apple-darwin9.6.0) libcurl/7.19.5 zlib/1.2.3
> Host: localhost:5984
> Accept: */*
> 
< HTTP/1.1 200 OK
< Server: CouchDB/0.9.0 (Erlang OTP/R13B)
< Etag: "2-2518059090"
< Date: Thu, 04 Jun 2009 13:30:06 GMT
< Content-Type: text/plain;charset=utf-8
< Content-Length: 48
< Cache-Control: must-revalidate
< 
{"ok":true,"id":"testdoc","rev":"2-2518059090"}
* Connection #0 to host localhost left intact
* Closing connection #0

次にMapReduceを試すために以下の１０件のデータを登録。名前と年齢です。

curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro1\", \"age\":\"11\"}" http://localhost:5984/test/person1
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro2\", \"age\":\"12\"}" http://localhost:5984/test/person2
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro3\", \"age\":\"21\"}" http://localhost:5984/test/person3
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro4\", \"age\":\"22\"}" http://localhost:5984/test/person4
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro5\", \"age\":\"23\"}" http://localhost:5984/test/person5
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro6\", \"age\":\"31\"}" http://localhost:5984/test/person6
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro7\", \"age\":\"32\"}" http://localhost:5984/test/person7
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro8\", \"age\":\"33\"}" http://localhost:5984/test/person8
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro9\", \"age\":\"34\"}" http://localhost:5984/test/person9
curl -v -X PUT -H "Content-Type: application/json" --data "{\"name\":\"taro10\", \"age\":\"35\"}" http://localhost:5984/test/person10

１０件登録されてますね。

Map

function(doc) {
  if(doc.age > 30) {
    emit(null, 1);
  }
}

Reduce

function(keys,values) {
  return sum(values);
}

で、三十路を超えた人の数を数えています。

参考にしたもの

• http://blogs.ricollab.jp/webtech/2008/06/couchdb/
• Web 時代の非リレーショナルデータベース: 第 1 回 Apache CouchDB の概要とインストール
• CouchDB を探る