Question

我使用node.js编写游戏，我使用Postgres包作为名为pg的节点。我插入数据库的所有内容都有效。也可以检索插入的数据。即使重新启动dyno，数据仍然存在。

插入的数据不超过几行。

但是在一天左右之后，表中不存在插入的数据。我阅读了Heroku文档，但无法找到原因。

出了什么问题？

我正在使用Heroku的免费等级和Postgres的爱好开发计划。

修改

我的数据库代码如下：

// I need to delete the rows from the database which are one day old, one week old and the third table not at all old
var flushTable = function(tableName, dateObj, callback) {
    var client = null, query = null;
    var strDate = getDateString(dateObj);
    client = new pg.Client(connectionString);
    client.connect();
    query = client.query('DELETE FROM '+tableName+' WHERE latest_date<TO_DATE(\''+strDate+'\',\'YYYY-MM-DD\');', function(err, result) {
        if(err) {
            console.log(err);
            client.end();
            return;
        }
        client.end();
        callback();
    });
};
var createNonExistent = function(tableName, callback) {
    var client = null, query = null;
    client = new pg.Client(connectionString);
    client.connect();
    query = client.query('CREATE TABLE IF NOT EXISTS  '+tableName+' (username VARCHAR(16) PRIMARY KEY NOT NULL, score INTEGER NOT NULL, latest_date DATE NOT NULL, latest_time TIME NOT NULL, ip VARCHAR(30) NOT NULL);', function(err, result) {
        if (err) {
            console.log(err);
            client.end();
            return;
        }
        console.log('Table Created');
        client.end();
        callback();
    });
}
var readFromTable = function(tableName, callback) {
    flushTable(tableName, new Date(), function(){
        var client = null, query = null;
        client = new pg.Client(connectionString);
        client.connect();
        query = client.query('SELECT * FROM '+tableName+' ORDER BY score DESC, latest_date DESC, latest_time DESC;', function(err, result){
            if(err) {
                console.log(err);
                client.end();
                return;
            }
            console.log('Read values');
            console.log(result.rows);
            client.end();
            callback(result);
        });
    });
};

Answer 1

我想到了错误，我没有更改代码中的日期，所以我添加了另一个名为flushAll（）的函数，我在读写之前调用了它。

函数flushAll（）正确删除表，而不像readTable（）函数中的删除那样。

以下是修改后的代码：

var flushTable = function(tableName, dateObj, callback) {
    var client = null, query = null;
    var strDate = getDateString(dateObj);
    client = new pg.Client(connectionString);
    client.connect();
    query = client.query('DELETE FROM '+tableName+' WHERE latest_date<TO_DATE(\''+strDate+'\',\'YYYY-MM-DD\');', function(err, result) {
        if(err) {
            console.log(err);
            client.end();
            return;
        }
        client.end();
        callback();
    });
};
var createNonExistent = function(tableName, callback) {
    var client = null, query = null;
    client = new pg.Client(connectionString);
    client.connect();
    query = client.query('CREATE TABLE IF NOT EXISTS  '+tableName+' (username VARCHAR(16) PRIMARY KEY NOT NULL, score INTEGER NOT NULL, latest_date DATE NOT NULL, latest_time TIME NOT NULL, ip VARCHAR(30) NOT NULL);', function(err, result) {
        if (err) {
            console.log(err);
            client.end();
            return;
        }
        console.log('Table Created');
        client.end();
        callback();
    });
}
var flushAll = function(callback) {
    flushTable('today',new Date(), function(){
        var dateObj = new Date();
        var strDate = getDateString(dateObj);
        while (dateObj.getDay() != 0) {
            dateObj.setDate(dateObj.getDate()-1);
        }
        flushTable('thisweek',new Date(), function(){
            callback();     
        });
    });
}
var readFromTable = function(tableName, callback) {
    var client = null, query = null;
    client = new pg.Client(connectionString);
    client.connect();
    query = client.query('SELECT * FROM '+tableName+' ORDER BY score DESC, latest_date DESC, latest_time DESC;', function(err, result) {
        if(err) {
            console.log(err);
            client.end();
            return;
        }
        console.log('Read values');
        console.log(result.rows);
        client.end();
        callback(result);
    });
};
exports.readLeaderBoards = function(callback) {
    var boards = [];
    flushAll(function(){
        createNonExistent('alltime', function(){
            createNonExistent('thisweek', function(){
                createNonExistent('today', function(){
                    readFromTable('today', function(result) {
                        boards['today'] = result.rows;
                        readFromTable('thisweek', function(result) {
                            boards['thisweek'] = result.rows;
                            readFromTable('alltime', function(result) {
                                boards['alltime'] = result.rows;
                                console.log(boards['today']);
                                callback(boards);
                            });
                        });
                    });
                });
            });
        });
    });
};

一段时间后，关于Heroku数据的业余爱好层爱好开发postgres消失了

1 个答案: