Question

我正在使用从npm安装的node-sqlite3。这个问题与该特定插件有关。我通过节点运行以下命令：

node select.js

var sqlite3 = require('sqlite3').verbose();
var db = new sqlite3.Database('foods.db');

db.serialize(function() {

    db.each(
"select foods.name, food_types.name from foods, food_types where foods.type_id=food_types.id limit 10;"

        , function(err, row){
        if(err) {
            console.log(err);
        }
        console.log(row);
    });

})
db.close();

此代码返回

{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }
{ name: 'Bakery' }

但是使用sqlite3

select foods.name, food_types.name from foods, food_types where foods.type_id=food_types.id limit 10;

返回（带.headers on，.mode列）

name        name      
----------  ----------
Bagels      Bakery    
Bagels, ra  Bakery    
Bavarian C  Bakery    
Bear Claws  Bakery    
Black and   Bakery    
Bread (wit  Bakery    
Butterfing  Bakery    
Carrot Cak  Bakery    
Chips Ahoy  Bakery    
Chocolate   Bakery

我是否错误地使用了node-sqlite3 npm模块，我希望看到类似

的内容

{ name: 'Bakery', name: 'Bagels' }
{ name: 'Bakery',  name: 'Bagels, ra'}
{ name: 'Bakery', name: 'Bavarian C' }
{ name: 'Bakery', name: 'Bear Claws' }

等...

Answer 1

SQLite模块无法使用相同的键两次返回结果对象;一个值必须覆盖另一个。您可以通过在SQL中使用as为其中一列指定其他名称来解决此问题：

select foods.name as name_food, food_types.name as name_type from ...

以上将给出如下结果：

{ name_type: 'Bakery', name_food: 'Bagels' }
{ name_type: 'Bakery', name_food: 'Bagels, ra'}
{ name_type: 'Bakery', name_food: 'Bavarian C' }
{ name_type: 'Bakery', name_food: 'Bear Claws' }
...

node-sqlite3从多个表中选择列

1 个答案: