Open source databases rise and fall on the popularity of the programming languages which use those databases. ...

While the future is unpredictable, the current momentum in programming languages is behind two platforms: Node.js and Go.  PostgreSQL already enjoys good support and adoption among Go users.  However, our adoption in the Node.js community is less encouraging.

I was given a set of statistics I'm not allowed to publish, but I can summarize them.  Two of them are fairly alarming:

• PostgreSQL is the database for fewer than 1 out of 8 Node.js deployments which use a database.

• The rise in popularity of MongoDB almost exactly parallels the rise in usage of Node.js.

If you've watched database adoption trends for the last 20 years like I have, this is alarming.  We are in danger of being sidelined....

What do Node.js users want that we don't have?  There's three main things that I've been able to identify:

1. A better, faster, driver which fully supports asynchronous querying.

2. Relatively painless multi-node scaling

3. Full, indexed support for jsonish hierarchical data and queries.

它对什么有好处？

正如您此前所看到的，Node 非常适合以下情况：在响应客户端之前，您预计可能有很高的流量，但所需的服务器端逻辑和处理不一定很多。Node 表现出众的典型示例包括：

RESTful API

提供 RESTful API 的 Web 服务接收几个参数，解析它们，组合一个响应，并返回一个响应（通常是较少的文本）给用户。这是适合 Node 的理想情况，因为您可以构建它来处理数万条连接。它仍然不需要大量逻辑；它本质上只是从某个数据库中查找一些值并将它们组成一个响应。由于响应是少量文本，入站请求也是少量的文本，因此流量不高，一台机器甚至也可以处理最繁忙的公司的 API 需求。

-- 照片中的人的信息表，用JSONB实现，JSONB数组形式，即一行对应普通表的多行

DROP TABLE IF EXISTS R_PIC_PERSON_JSONB_USEARRAY CASCADE;

CREATE TABLE R_PIC_PERSON_JSONB_USEARRAY (

id serial,-- 照片id

persons jsonb NOT NULL -- 格式为：[{"position":"前1排左1","name":"张晓陆","phone":"18910180100","city":"济南","organization":"中科院计算所","attendanceYear":2012,"graduationYear":2016},{"position":"前1排左2","name":"张晓陆","phone":"18910180100","organization":"中科院计算所","attendanceYear":2012,"graduationYear":2016}]

)WITH (OIDS=FALSE);

insert into R_PIC_PERSON_JSONB_USEARRAY values

(1,

'[{"position":"前1排左1","name":"张晓陆","phone":"18910180100","city":"济南","organization":"中科院计算所","attendanceYear":2012,"graduationYear":2016},

{"position":"前1排左2","name":"张晓陆2","phone":"18910180100","organization":"中科院计算所","attendanceYear":2012,"graduationYear":2016}]'

);

URLHTTP       Verb       Action

/api/pic/persons    GET      返回该图片中的所有人，需要传入参数：图片的id

/api/pic/person/:idx  GET        返回图片中第idx个人

/api/pic/persons    POST        增加一个人

/api/pic/person/:idx   PUT        更新一个人

/api/pic/person/:idx   DELETE      删除一个人

router.get('/api/pic/persons', db.getPicAllPersons);

router.get('/api/pic/person/:idx', db.getPicSinglePerson);

router.post('/api/pic/persons', db.createPicPerson);

router.put('/api/pic/person/:idx', db.updatePicPerson);

router.delete('/api/pic/person/:idx', db.removePicPerson);

function getPicAllPersons(req, res, next) {

 var picID = parseInt(req.query.id);

 db.one('select * from R_PIC_PERSON_JSONB_USEARRAY where id = $1', picID)

   .then(function (data) {

     res.status(200)

       .json({

         status: 'success',

         data: data,

         message: 'Retrieved ALL persons in a pic'

       });

   })

   .catch(function (err) {

     return next(err);

   });

}

var personIdx = parseInt(req.params.idx);

var picID = parseInt(req.query.id);

 db.one('select a.id,a.persons->$1 as person from R_PIC_PERSON_JSONB_USEARRAY a  where a.id = $2', [personIdx,picID])

   .then(function (data) {

     res.status(200)

       .json({

         status: 'success',

         data: data,

         message: 'Retrieved ONE PERSON'

       });

   })

   .catch(function (err) {

     return next(err);

   });

}

var aPersonJson = req.body;

var picID = parseInt(req.query.id);

 db.none('update R_PIC_PERSON_JSONB_USEARRAY set persons = persons || $1  where  id =  $2',[aPersonJson,picID])

   .then(function () {

     res.status(200)

       .json({

         status: 'success',

         message: 'Inserted one person'

       });

   })

   .catch(function (err) {

     return next(err);

   });

}