Home Web Front-end JS Tutorial How to query a piece of data in node.js

How to query a piece of data in node.js

Dec 16, 2021 am 11:46 AM
node.js

Node.js method to query a piece of data: 1. Create relevant js files; 2. Query a piece of data through the code "const MongodbClient = require("mongodb").MongoClient,assert = require..." Can.

How to query a piece of data in node.js

The operating environment of this article: windows7 system, mongodb nodeJS driver version 3.2.3, Dell G3 computer.

node.js How to query a piece of data?

NodeJs uses mongodb to query a piece of data

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源代码请查看GitHub:https://github.com/slhuang520/study/tree/master/web/nodeJS/mongoDB/findOne.js

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The currently used mongodb nodeJS driver version is 3.2.3,

Different Driver versions, the methods are very different difference.

When querying a piece of data, you can also use sorting or certain conditions.

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const MongodbClient = require("mongodb").MongoClient,

    assert = require("assert");

(async () => {

    const url = "mongodb://127.0.0.1:27017",

        dbName = "mydb",

        client = new MongodbClient(url);

    try {

        await client.connect();

        const db = client.db(dbName);

        let col = await db.collection("user");

        col.findOne().then(res => {

            console.log(res); //{ _id: 5ccd913ef78b417285224075, name: 'Jim', age: 12 }

        });

    } catch (e) {

        console.log(e.stack);

    } finally {

        client.close();

    }

})();

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