$gte - Amazon DocumentDB

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$gte

$gte聚合运算符比较两个值,true如果第一个值大于或等于第二个值,则返回,否则返回false

参数

  • expression1:要比较的第一个值。

  • expression2: 第二个要比较的值。

示例(MongoDB 外壳)

以下示例演示如何使用$gte运算符来检查学生是否通过了考试。

创建示例文档

db.students.insertMany([ { _id: 1, name: "Alice", score: 85 }, { _id: 2, name: "Bob", score: 60 }, { _id: 3, name: "Charlie", score: 72 } ]);

查询示例

db.students.aggregate([ { $project: { name: 1, score: 1, passed: { $gte: ["$score", 70] } } } ]);

输出

[ { _id: 1, name: 'Alice', score: 85, passed: true }, { _id: 2, name: 'Bob', score: 60, passed: false }, { _id: 3, name: 'Charlie', score: 72, passed: true } ]

代码示例

要查看使用$gte聚合运算符的代码示例,请选择要使用的语言的选项卡:

Node.js
const { MongoClient } = require('mongodb'); async function example() { const client = await MongoClient.connect('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false'); const db = client.db('test'); const collection = db.collection('students'); const result = await collection.aggregate([ { $project: { name: 1, score: 1, passed: { $gte: ["$score", 70] } } } ]).toArray(); console.log(result); await client.close(); } example();
Python
from pymongo import MongoClient def example(): client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false') db = client['test'] collection = db['students'] result = list(collection.aggregate([ { '$project': { 'name': 1, 'score': 1, 'passed': { '$gte': ['$score', 70] } } } ])) print(result) client.close() example()