如何使用 node.js 和连接池同时建立多个到 SQLServer 数据库的连接？

Question

我正在使用池连接构建一个带有 SQLServer 数据库的 node.js 应用程序。它具有异步功能，每个人都应该在完成后将一条记录保存到数据库中。问题是只插入了 10 个异步任务中的大约 10 条记录，其余的给出了这个错误 "Already connecting to database! Call close before connecting to different database.".

我尝试编辑池的配置，但没有成功。

var config = {
            host: "localhost",
            user: "test",
            password: "test",
            database: "testDB",
            server: '************',
            pool: {
                max: 20,
                maxWaitingClients:1,
                fifo:true,
                min: 0,
                idleTimeoutMillis: 30000
            }
        };

const pool = new sql.ConnectionPool(config);
pool.on('error', err => {
    console.error('SQLServer Pool Error: ', err.toString());
});

async writeToDB(System, url, PortListening, RequestTest, time, TestType, Request, Response, responseTime, pool) {
        try {
            var query = "INSERT INTO `testTable` " +
                "(SystemName,URL,PortListening,RequestTest,TestDate,TestType,Request,Response,ResponseTime) " +
                "VALUES " +
                "('" + System + "','" + url + "','" + PortListening + "','" + RequestTest + "','" + time + "','" + TestType + "',N'" + Request + "',N'" + Response + "'," + responseTime + ")";

            await pool.connect();
            let result =await  pool.request().query(query);

            return {success: result};
        } catch (err) {
            console.log(System);
            console.error(err);
            return {err: err};
        } finally {
            pool.close();
         }
    }

它应该插入所有异步任务中的所有行而不会丢失任何数据。

Answer 1

从池设置中省略 maxWaitingClients。让客户端自动处理。

Answer 2

我找到了答案。我应该在应用程序启动时打开池 "pool.connect()" 一次，然后在应用程序关闭之前将其关闭。所以代码应该是这样的：

var config = {
        host: "localhost",
        user: "test",
        password: "test",
        database: "testDB",
        server: '************',
        pool: {
            max: 20,
            maxWaitingClients:1,
            fifo:true,
            min: 0,
            idleTimeoutMillis: 30000
        }
    };

const pool = new sql.ConnectionPool(config);
pool.on('error', err => {
    console.error('SQLServer Pool Error: ', err.toString());
});

pool.connect();

async writeToDB(System, url, PortListening, RequestTest, time, TestType, Request, Response, responseTime, pool) {
        try {
            var query = "INSERT INTO `testTable` " +
                "(SystemName,URL,PortListening,RequestTest,TestDate,TestType,Request,Response,ResponseTime) " +
                "VALUES " +
                "('" + System + "','" + url + "','" + PortListening + "','" + RequestTest + "','" + time + "','" + TestType + "',N'" + Request + "',N'" + Response + "'," + responseTime + ")";



     let result =await  pool.request().query(query);
    } catch (err) {
        return {err: err};
    } 
}

如何使用 node.js 和连接池同时建立多个到 SQLServer 数据库的连接？

How to make multiple connections at once to a SQLServer database by using node.js and connection pooling?

javascript

sql-server

connection-pooling

node.js