mongodb 猫鼬查询其中值不为空
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Mongoose query where value is not null
提问by wesbos
Looking to do the following query:
希望执行以下查询：
Entrant
.find
enterDate : oneMonthAgo
confirmed : true
.where('pincode.length > 0')
.exec (err,entrants)->
Am I doing the where clause properly? I want to select documents where pincodeis not null.
我是否正确执行 where 子句？我想选择pincode不为空的文档。
回答by numbers1311407
You should be able to do this like (as you're using the query api):
您应该可以这样做（因为您正在使用查询 api）：
Entrant.where("pincode").ne(null)
... which will result in a mongo query resembling:
...这将导致一个 mongo 查询类似于：
entrants.find({ pincode: { $ne: null } })
A few links that might help:
一些可能有帮助的链接：
回答by MalcolmOcean
I ended up here and my issue was that I was querying for
我最终到了这里，我的问题是我正在查询
{$not: {email: /@domain.com/}}
instead of
代替
{email: {$not: /@domain.com/}}
回答by Tính Ng? Quang
selects the documents where the value of the field is not equal to the specified value. This includes documents that do not contain the field.
选择字段值不等于指定值的文档。这包括不包含该字段的文档。
User.find({ "username": { "$ne": 'admin' } })
$nin selects the documents where: the field value is not in the specified array or the field does not exist.
$nin 选择以下文档：字段值不在指定数组中或字段不存在。
User.find({ "groups": { "$nin": ['admin', 'user'] } })
回答by Vadivel Subramanian
total count the documents where the value of the field is not equal to the specified value.
总计统计字段值不等于指定值的文档。
async function getRegisterUser() {
return Login.count({"role": { $ne: 'Super Admin' }}, (err, totResUser) => {
if (err) {
return err;
}
return totResUser;
})
}
