Tom*_*Tom 28 node.js sequelize.js
我有一个Article
Sequelize模型,其中的文章彼此相关.有些文章是其他文章的翻译副本.关系设置如下:
var Article = sequelize.define('Article', {
type : DataTypes.ENUM('source', 'translated'),
sourceArticleId : DataTypes.INTEGER
});
db.Article.hasMany(db.Article, {
foreignKey: 'sourceArticleId',
as : 'TranslatedArticles'
});
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所以,一篇文章type = 'source'
可以有很多translatedArticles
地方type = 'translated'
.
现在,我想查询所有source
没有翻译的文章.
基于Sequelize项目github上的一个问题,这将完成如下:
Article.findOne({
where: Sequelize.literal('translatedArticles.sourceArticleId IS NULL'),
include: [
{
model: Article,
as : 'TranslatedArticles'
}
]
});
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然而,当我运行这个时,我得到:
SequelizeDatabaseError: ER_BAD_FIELD_ERROR: Unknown column 'translatedArticles.sourceArticleId' in 'where clause'
我也试过变化的命名,其中包括TranslatedArticles.sourceArticleId
,articles.sourceArticleId
,和Articles.sourceArticleId
.
我错过了什么吗?
请注意,我通过使用文字NOT EXISTS查询暂时解决此问题,如下所示:
Article.findOne({
where: Sequelize.literal('NOT EXISTS (SELECT id FROM Articles WHERE Article.id = Articles.sourceArticleId LIMIT 1)')
});
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我在这里胡思乱想,但我认为这就是实现的方式:
Article.findOne({
include: [
{
model: Article,
as : 'TranslatedArticles',
attributes: [[models.sequelize.fn('COUNT', 'sourceArticleId'), 'translationCount']]
having: {
translationCount: 0
},
}
]
});
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