Step 5: Query data in a table

In this step, you query the data that you wrote to the Music table in Step 2: Write data to a table using the console or AWS CLI by specifying Artist. This will display all songs that are associated with the partition key: Artist.

For more information about query operations, see Query operations in DynamoDB.

AWS Management Console

Follow these steps to use the DynamoDB console to query data in the Music table.

1. Open the DynamoDB console at https://console.aws.amazon.com/dynamodb/.

2. In the left navigation pane, choose Tables.

3. Choose the Music table from the table list.

4. Choose Explore table items.

5. In Scan or query items, make sure that Query is selected.

6. For Partition key, enter Acme Band, and then choose Run.

AWS CLI

The following AWS CLI example queries an item in the Music table. You can do this either through the DynamoDB API or PartiQL, a SQL-compatible query language for DynamoDB.

DynamoDB API

You query an item through the DynamoDB API by using query and providing the partition key.

Linux

aws dynamodb query \
    --table-name Music \
    --key-condition-expression "Artist = :name" \
    --expression-attribute-values  '{":name":{"S":"Acme Band"}}'

Windows CMD

aws dynamodb query ^
    --table-name Music ^
    --key-condition-expression "Artist = :name" ^
    --expression-attribute-values  "{\":name\":{\"S\":\"Acme Band\"}}"

Using query returns all the songs associated with this particular Artist.

{
    "Items": [
        {
            "AlbumTitle": {
                "S": "Updated Album Title"
            },
            "Awards": {
                "N": "10"
            },
            "Artist": {
                "S": "Acme Band"
            },
            "SongTitle": {
                "S": "Happy Day"
            }
        },
        {
            "AlbumTitle": {
                "S": "Another Album Title"
            },
            "Awards": {
                "N": "8"
            },
            "Artist": {
                "S": "Acme Band"
            },
            "SongTitle": {
                "S": "PartiQL Rocks"
            }
        }
    ],
    "Count": 2,
    "ScannedCount": 2,
    "ConsumedCapacity": null
}

PartiQL for DynamoDB

You query an item through PartiQL by using the Select statement and providing the partition key.

Linux

aws dynamodb execute-statement --statement "SELECT * FROM Music   \
                                            WHERE Artist='Acme Band'"

Windows CMD

aws dynamodb execute-statement --statement "SELECT * FROM Music WHERE Artist='Acme Band'"

Using the Select statement in this way returns all the songs associated with this particular Artist.

{
    "Items": [
        {
            "AlbumTitle": {
                "S": "Updated Album Title"
            },
            "Awards": {
                "S": "10"
            },
            "Artist": {
                "S": "Acme Band"
            },
            "SongTitle": {
                "S": "Happy Day"
            }
        },
        {
            "AlbumTitle": {
                "S": "Another Album Title"
            },
            "Awards": {
                "S": "8"
            },
            "Artist": {
                "S": "Acme Band"
            },
            "SongTitle": {
                "S": "PartiQL Rocks"
            }
        }
    ]
}

For more information about querying data with PartiQL, see PartiQL select statements.

To create a global secondary index for your table, proceed to Step 6: Create a global secondary index.