使用nodejs Dynamodb 创建表？

Question

I want to create a table and want to create 6-7 columns/attributes using Dynamodb(NodeJs). I have created a table but I am not able to add more than 2 attributes.I am new to this platform, can anyone help me to create multiple attributes in one table.

Answer 1

On DynamoDB, you must define only the Hash Key and optionally a Sort Key for your table. The rest of the attributes don't have to be defined! You can push whatever data you want.

Check out the example below, based on the official docs .

I'm creating a table Movies with Hash: Year and Sort: Title . Then I'm creating a movie with more attributes:

var AWS = require("aws-sdk");

AWS.config.update({
  region: "us-west-2",
  endpoint: "http://localhost:8000"
});

var client = new AWS.DynamoDB();
var documentClient = new AWS.DynamoDB.DocumentClient();

var tableName = "Movies";

var params = {
    TableName: tableName,
    KeySchema: [
        { AttributeName: "year", KeyType: "HASH"},  //Partition key
        { AttributeName: "title", KeyType: "RANGE" }  //Sort key
    ],
    AttributeDefinitions: [
        { AttributeName: "year", AttributeType: "N" },
        { AttributeName: "title", AttributeType: "S" }
    ],
    ProvisionedThroughput: {
        ReadCapacityUnits: 10,
        WriteCapacityUnits: 10
    }
};

client.createTable(params, function(tableErr, tableData) {
    if (tableErr) {
        console.error("Error JSON:", JSON.stringify(tableErr, null, 2));
    } else {
        console.log("Created table successfully!");
    }

    // Adding Batman movie to our collection
    var params = {
        TableName: tableName,
        Item: {
            "year": 2005,
            "title": "Batman Begins",
            "info": {
                "plot": "A young Bruce Wayne (Christian Bale) travels to the Far East.",
                "rating": 0
            }
        }
    };

    console.log("Adding a new item...");
    documentClient.put(params, function(err, data) {
        if (err) {
            console.error("Error JSON:", JSON.stringify(err, null, 2));
        } else {
            console.log("Added item successfully!");
        }
    });
});

Answer 2

In dynamoDB, attributes will created automatically when you add an Item to the db.

While creating a table, we only specify the primary key and an optional sort key.

Answer 3

here is an example of creating a table on DynamoDB using nodejs AWS-SDK

 // Imports const AWS = require('aws-sdk') AWS.config.update({ region: 'eu-west-3' }); // Declare local variables const dynamo = new AWS.DynamoDB(); createTable('your table name') .then(data => console.log(data)) function createTable (tableName) { const params = { TableName: tableName, AttributeDefinitions: [ // required attributes to be used as keys { AttributeName: 'id', AttributeType: 'N' } ], KeySchema: [ { AttributeName: 'id', KeyType: 'HASH' } ], ProvisionedThroughput: { ReadCapacityUnits: 5, // Eventually Consistent Model WriteCapacityUnits: 5 } } return new Promise((resolve, reject) => { dynamo.createTable(params, (err, data) => { if(err) reject(err); else resolve(data); }) }) }