我可以要求在mongodb集合中设置属性吗? (不为null) [英] Can I require an attribute to be set in a mongodb collection? (not null)

问题描述

我可以在mongodb中定义需要设置某些属性的架构.类似于SQL中的NOT NULL.如果可能的话.这是什么语法?

Can I define a schema in mongodb which requires certain attributes to be set. Much like NOT NULL in SQL. If that is possible. What is the syntax for this?

我正在使用node.js和猫鼬. 猫鼬v3.6.15 mongodb v2.4.5

I am using node.js and mongoose. mongoose v3.6.15 mongodb v2.4.5

修改 Charles A提供的答案是正确的，但通过查阅文档，我发现在猫鼬中，还可以根据架构定义的要求定义一个字段，如下所示:

Edit The answer provided by Charles A is correct but looking through the documentation I found that in mongoose it is also possible to define a field as required in the schema defenition like this:

foo : {
    bar : { type : String, required : true }
}

推荐答案

在Mongoose中，您可以使用 validator 在保存之前检查是否已设置字段.据我所知，无法在Schema上指定需要一个字段，因此它需要更多样板代码.

In Mongoose, you can use a validator to check if a field has been set before you save it. As far as I know, there is no way of specifying on a Schema that a field is required, so it requires a little more boilerplate code.

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