步骤 3：使用 Node.js 连接到 SQL 的概念证明

下载 Node.js SQL 驱动程序

应只将此示例视为概念证明。 为清楚起见，示例代码已简化，不一定代表 Microsoft 建议的最佳做法。 GitHub 上提供了其他使用相同关键函数的示例：

• https://github.com/tediousjs/tedious/blob/master/examples/

步骤 1：连接

new Connection 函数用于连接到 SQL 数据库。

    var Connection = require('tedious').Connection;  
    var config = {  
        server: 'your_server.database.windows.net',  //update me
        authentication: {
            type: 'default',
            options: {
                userName: 'your_username', //update me
                password: 'your_password'  //update me
            }
        },
        options: {
            // If you are on Microsoft Azure, you need encryption:
            encrypt: true,
            database: 'your_database'  //update me
        }
    };  
    var connection = new Connection(config);  
    connection.on('connect', function(err) {  
        // If no error, then good to proceed.
        console.log("Connected");  
    });
    
    connection.connect();

步骤 2：执行查询

所有 SQL 语句都是使用 new Request() 函数执行的。 如果语句返回了行（如 SELECT 语句），你可以使用 request.on() 函数检索这些行。 如果未返回行，request.on() 函数返回空列表。

    var Connection = require('tedious').Connection;  
    var config = {  
        server: 'your_server.database.windows.net',  //update me
        authentication: {
            type: 'default',
            options: {
                userName: 'your_username', //update me
                password: 'your_password'  //update me
            }
        },
        options: {
            // If you are on Microsoft Azure, you need encryption:
            encrypt: true,
            database: 'your_database'  //update me
        }
    }; 
    var connection = new Connection(config);  
    connection.on('connect', function(err) {  
        // If no error, then good to proceed.  
        console.log("Connected");  
        executeStatement();  
    });  
    
    connection.connect();
  
    var Request = require('tedious').Request;  
    var TYPES = require('tedious').TYPES;  
  
    function executeStatement() {  
        var request = new Request("SELECT c.CustomerID, c.CompanyName,COUNT(soh.SalesOrderID) AS OrderCount FROM SalesLT.Customer AS c LEFT OUTER JOIN SalesLT.SalesOrderHeader AS soh ON c.CustomerID = soh.CustomerID GROUP BY c.CustomerID, c.CompanyName ORDER BY OrderCount DESC;", function(err) {  
        if (err) {  
            console.log(err);}  
        });  
        var result = "";  
        request.on('row', function(columns) {  
            columns.forEach(function(column) {  
              if (column.value === null) {  
                console.log('NULL');  
              } else {  
                result+= column.value + " ";  
              }  
            });  
            console.log(result);  
            result ="";  
        });  
  
        request.on('done', function(rowCount, more) {  
        console.log(rowCount + ' rows returned');  
        });  
        
        // Close the connection after the final event emitted by the request, after the callback passes
        request.on("requestCompleted", function (rowCount, more) {
            connection.close();
        });
        connection.execSql(request);  
    }  

步骤 3：插入行

此示例展示了如何安全执行 INSERT 语句，并传递用于保护应用程序免遭 SQL 注入值影响的参数。

    var Connection = require('tedious').Connection;  
    var config = {  
        server: 'your_server.database.windows.net',  //update me
        authentication: {
            type: 'default',
            options: {
                userName: 'your_username', //update me
                password: 'your_password'  //update me
            }
        },
        options: {
            // If you are on Microsoft Azure, you need encryption:
            encrypt: true,
            database: 'your_database'  //update me
        }
    };  
    var connection = new Connection(config);  
    connection.on('connect', function(err) {  
        // If no error, then good to proceed.  
        console.log("Connected");  
        executeStatement1();  
    });
    
    connection.connect();
    
    var Request = require('tedious').Request  
    var TYPES = require('tedious').TYPES;  
  
    function executeStatement1() {  
        var request = new Request("INSERT SalesLT.Product (Name, ProductNumber, StandardCost, ListPrice, SellStartDate) OUTPUT INSERTED.ProductID VALUES (@Name, @Number, @Cost, @Price, CURRENT_TIMESTAMP);", function(err) {  
         if (err) {  
            console.log(err);}  
        });  
        request.addParameter('Name', TYPES.NVarChar,'SQL Server Express 2014');  
        request.addParameter('Number', TYPES.NVarChar , 'SQLEXPRESS2014');  
        request.addParameter('Cost', TYPES.Int, 11);  
        request.addParameter('Price', TYPES.Int,11);  
        request.on('row', function(columns) {  
            columns.forEach(function(column) {  
              if (column.value === null) {  
                console.log('NULL');  
              } else {  
                console.log("Product id of inserted item is " + column.value);  
              }  
            });  
        });

        // Close the connection after the final event emitted by the request, after the callback passes
        request.on("requestCompleted", function (rowCount, more) {
            connection.close();
        });
        connection.execSql(request);  
    }