phpactiverecord无法创建对象-undefined属性

Question

我正在测试PHP Active Record，但我面临一些问题。

设置AR

    ActiveRecord\Config::initialize(function($cfg)
    {
        $cfg->set_model_directory( __DIR__ . '/models');
        $cfg->set_connections(array(
            'development' => 'sqlite://:memory:' ));
    });

models/Author.php

class Author extends ActiveRecord\Model
{
    static $table_name = 'author';
}

models/Book.php

<?php

class Book extends ActiveRecord\Model
{
    static $table_name = 'book';

        static $belongs_to = array(
            array('author')
        );

}

创建新作者

$author = new Author();
$author->first_name = 'John';
$author->save();

创建新帐簿

$book = new Book();
$book->title = 'Dead men tell no tales.';
$book->save();

创建author表

CREATE TABLE [author]
        (
            [id] INTEGER  NOT NULL PRIMARY KEY,
            [first_name] VARCHAR(128)  NOT NULL
        )

创建book表

CREATE TABLE [book]
        (
            [id] INTEGER  NOT NULL PRIMARY KEY,
            [title] VARCHAR(255)  NOT NULL,
            [author_id] INTEGER,
            FOREIGN KEY (author_id) REFERENCES author(id)
        )

创建author对象似乎很好，但创建一本书会引发异常

 Uncaught ActiveRecord\UndefinedPropertyException: Undefined property: Book->author_id

使用标准PDO查询数据库似乎运行良好...所以我想知道我是不是在Php活动记录中遗漏了什么

Answer 1

author_id是一个非空的外键，因此必须始终在插入时指定：

$book = new Book();
$book->title = 'Dead men tell no tales.';
$book->author_id = 1; // replace this value with an appropriate one.
$book->save();