amazon-web-servicesgoamazon-dynamodbaws-sdkaws-sdk-go

How to get data from aws Dynamodb with using partition key only?


I am using aws-sdk-go library for DynamoDb connectivity in Golang.

My DynamoDb table have a Partition key DeviceId (String) and a Sort Key Time (Number). How can I write GetItemInput to get all data with a specific DeviceId?

params := &dynamodb.GetItemInput{

    Key:    map[string]*dynamodb.AttributeValue {
        "DeviceId": {
            S: aws.String("item_1"),
        },
    },
    ExpressionAttributeNames: map[string]*string{
        "DeviceId": "DeviceId",
    },
    TableName:  aws.String("DbName"), 
}

list, err := svc.GetItem(params)

Solution

  • You have to use Query or Scan operation, this is a simple example but you can read more on Amazon documentation here

    In particular, Query operation

    A Query operation finds items in a table or a secondary index using only primary key attribute values

    var queryInput = &dynamodb.QueryInput{
        TableName: aws.String(dynamoRestDataTableName),
        KeyConditions: map[string]*dynamodb.Condition{
            "DeviceId": {
                ComparisonOperator: aws.String("EQ"),
                AttributeValueList: []*dynamodb.AttributeValue{
                    {
                        S: aws.String("aDeviceId"),
                    },
                },
            },
        },
    }
    
    var resp, err = dynamoSvc.Query(queryInput)
    if err != nil {
        return nil, err
    }