javascript - 从 postgre 到 mysql 的 npm sql 池

Question

我有这个代码:

    console.log("-------------- Connecting to the database...");
    const client = await pool.connect();
    console.log("-------------- Connection process done.");
    console.log("-------------- Now Querying.");  
    var sql = `SELECT * FROM users WHERE email = '${email}'`;
    console.log("-------------- Query done.");
    let query = await client.query(sql);
    client.release();
    pool.release();
    if(query.rows[0]){return "Email already exists. Please login."}
    return 0;

我想这样做:

    pool.getConnection

我该怎么办？

Answer 1

我假设您在自述文件中使用 npm 包 mysql，您可以找到有关池主题的文档。

https://www.npmjs.com/package/mysql#pooling-connections

const mysql = require('mysql');
const pool  = mysql.createPool(...);

const email = "test@example.com" // Users email address variable.

pool.getConnection(function(err, connection) {
  if (err) throw err; // not connected!

  // Use the connection
  connection.query('SELECT * FROM users WHERE email = ?', [email], function (error, results, fields) {
    // When done with the connection, release it.
    connection.release();

    // Handle error after the release.
    if (error) throw error;

    // Don't use the connection here, it has been returned to the pool.

    if(!results.length) {
     // No results found.
    }else {
     // Results found.
    }
  });
});

我尚未测试此代码，如果您确实遇到问题，请查看文档。