Question

我正在尝试使用节点对PostgreSQL数据库执行更新，但我正在执行Error: Connection terminated执行UPDATE操作。在以适当的异步方式处理连接时，我可能会搞砸过早地终止它们，但是我无法理解我是如何正确执行它的。

对于大块代码感到抱歉，但它非常简单。

//main.js
var result = require('./processes.js');
result.check(function(message) {
    console.log(message);

});

result.decrease(); //Throws an error.


//workers.js
var pg = require ('pg');
var fs = require('fs');

var db = JSON.parse(fs.readFileSync('../config.json', 'utf8')).db;
var querydb = require('./querydb.js');

var self = module.exports = {
    check: function(callback) {
        querydb.select("SELECT size FROM workers WHERE id = 1", function(results) {
            callback(results[0].size);
        });
    },
    increase: function() {
        self.check(function(workers) {
            querydb.update("UPDATE workers SET size = " + (workers + 1) + " WHERE id = 1");
        });
    },
    decrease: function() {
        self.check(function(workers) {
            querydb.update("UPDATE workers SET size = " + (workers - 1) + " WHERE id = 1");
        });
    }
};


//querydb.js
var pg = require ('pg');
var fs = require('fs');

var db = JSON.parse(fs.readFileSync('../config.json', 'utf8')).db;

var select = function(statement, callback) {
    pg.connect(db, function(err, client, done) {
        var results = [];
        //Handle errors
        if(err) {
            done();
            console.log(err);
        }
        var query = client.query(statement);

        //Stream results back
        query.on('row', function(row) {
            results.push(row);
        });

        //When all data is returned.
        query.on('end', function() {
            done();
            callback(results);
            client.end();
        });
    });
}

var update = function(statement) {
    pg.connect(db, function(err, client, done) {
        var results = [];
        //Handle errors
        if(err) {
            done();
            console.log(err);
        }
        var query = client.query(statement);

        //When all data is returned.
        query.on('end', function() {
            done();
            client.end();
        });
    });
}

module.exports = {
    select: select,
    update: update
};

Answer 1

好吧，这可能不是本身的答案，而是更多的解决方法，但对这种脚本（即不是网络服务器）进行同步调用是我想要的所需行为，所以我最后使用pg-native代替pg并重构我的querydb和workers模块以使用它，现在一切正常！

Node.js PostgreSQL请求过早终止

1 个答案: