# RethinkDB

## RethinkDB(使用ReQL 為query language)

<https://www.rethinkdb.com/docs/quickstart/>

```
brew update && brew install rethinkdb
```

windows直接下載後點擊exe，在前往

```
http://localhost:8080/
```

使用Node.js

```
npm install rethinkdb
```

```
r = require('rethinkdb');

var connection = null;
r.connect( {host: 'localhost', port: 28015}, function(err, conn) {
    if (err) throw err;
    connection = conn;
    console.log(conn);
})
```

建立Table

```
r = require('rethinkdb');

r.connect( {host: 'localhost', port: 28015}, function(err, connection) {
    if (err) throw err;


    r.db('test').tableCreate('authors').run(connection, function(err, result) {
    if (err) throw err;
    console.log(JSON.stringify(result, null, 2));
});

});
```

```
generated_keys為主鍵的意思
```

## 取得資料

```
r = require('rethinkdb');

r.connect( {host: 'localhost', port: 28015}, function(err, connection) {
    if (err) throw err;


r.table('authors').run(connection, function(err, cursor) {
    if (err) throw err;
    cursor.toArray(function(err, result) {
        if (err) throw err;
        console.log(JSON.stringify(result, null, 2));
    });
});

});
```

## 體驗rethinkDB的realtime

```
r = require('rethinkdb');

r.connect( {host: 'localhost', port: 28015}, function(err, connection) {
    if (err) throw err;

r.table('authors').changes().run(connection, function(err, cursor) {
    if (err) throw err;
    cursor.each(function(err, row) {
        if (err) throw err;
        console.log(JSON.stringify(row, null, 2));
    });
});

});
```

執行後再開另一個CMD

檔案改成

```
r = require('rethinkdb');

r.connect( {host: 'localhost', port: 28015}, function(err, connection) {
    if (err) throw err;

r.table('authors').update({type: "fictional"}).
    run(connection, function(err, result) {
        if (err) throw err;
        console.log(JSON.stringify(result, null, 2));
    });

});
```

在另一個CMD執行server，發現兩個CMD都有console出現

參考至:<https://www.rethinkdb.com/docs/guide/javascript/>

<https://www.rethinkdb.com/docs/cookbook/javascript/>


---

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```
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```

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