Question

我正在编写代码以从数据库中获取数据并将其显示在服务器上。但是，当我在浏览器中运行命令localhost:3000时，该页面未显示，并且控制台上打印的错误是database "recipies" does not exist。但是，我有一个名为'recipies'的现有postgreSQL数据库，当我从postgreSQL控制台运行命令时，数据将插入并可以从表中查看。

问题是我有一个名为“ recipies”的现有数据库，但是错误显示数据库“ recipies”不存在。

代码：

var express = require('express'),
path = require('path'),
bodyParser = require('body-parser'),
cons = require('consolidate'),
dust = require('dustjs-helpers'),
pg = require('pg'),
app = express();


const config = {
    user: 'postgres',
    database: 'recipies',
    host: '40.83.121.72',
    password: 'HelloWorld',
    port: 5432
};

const connectionString = 'postgres://postgres:HelloWorld@localhost:3000/'


app.engine('dust',cons.dust);

app.set('view engine','dust');
app.set('views',__dirname+'/views');

app.use(express.static(path.join(__dirname,'public')));

app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended:false}));

const pool = new pg.Pool(config);

app.get('/', (req, res, next) => {
   pool.connect(function (err, client, done) {
       if (err) {
           console.log("Can not connect to the DB" + err);
       }
       client.query('SELECT * FROM recipies', function (err, result) {

            if (err) {
                console.log(err);
                res.status(400).send(err);
            }
            //res.status(200).send(result.rows);
            res.render('index',{recipies:result.rows});
            done();
       });
   });
});

app.listen(3000, function(){

console.log('Server started on port 3000');

});

错误：

 client.query('SELECT * FROM recipies', function (err, result) {
              ^

TypeError: Cannot read property 'query' of undefined
    at PendingItem.callback (F:\recipiebook2\app.js:72:15)
    at client.connect (F:\recipiebook2\node_modules\pg-pool\index.js:248:23)
    at Connection.connectingErrorHandler (F:\recipiebook2\node_modules\pg\lib\client.js:163:14)
    at Connection.emit (events.js:189:13)
    at Socket.<anonymous> (F:\recipiebook2\node_modules\pg\lib\connection.js:125:12)
    at Socket.emit (events.js:189:13)
    at addChunk (_stream_readable.js:284:12)
    at readableAddChunk (_stream_readable.js:265:11)
    at Socket.Readable.push (_stream_readable.js:220:10)
    at TCP.onStreamRead [as onread] (internal/stream_base_commons.js:94:17)

Answer 1

您的连接字符串不正确。应该是下面的样子。

const connectionString = 'postgres://db_username:db_password@localhost/db_name'

nodejs：数据库不存在

1 个答案: