猫鼬是否在选择中支持虚拟字段(例如SQL)
问题描述：
在SQL中，我可以使用状态"虚拟字段进行以下SELECT语句:
In SQL I can make the following SELECT statement with the 'status' virtual field:
SELECT
CASE
WHEN field = 1 THEN 'sale'
ELSE 'none'
END as status
猫鼬里有类似的东西吗?
Does something like is in mongoose?
答
是.猫鼬模式支持虚拟.请参阅指南的架构部分.我想您可能想要这样的东西:
Yes. Mongoose schemas support virtuals. Have a look at the schema section of the guide. I think you may want something like this:
var salesSchema = new Schema({
sale: Number
});
salesSchema.virtual('status').get(function() {
if (this.sale === 1) {
return 'sale';
} else {
return 'none';
}
});