How do I query GSI DynamoDB in Java?

Query a Global Secondary Index

1. Create an instance of the DynamoDB class.
2. Create an instance of the Table class to represent the index you want to work with.
3. Create an instance of the Index class for the index you want to query.
4. Call the query method on the Index object.

How do I query a DynamoDB global secondary index?

Open the DynamoDB console at .

1. In the navigation pane on the left side of the console, choose Tables.
2. Choose the Music table from the table list.
3. Select the View items.
4. Choose Query.
5. In the drop-down list under Query, choose AlbumTitle-index.

What is global secondary index in DynamoDB?

DynamoDB supports two types of secondary indexes: Global secondary index — An index with a partition key and a sort key that can be different from those on the base table. A global secondary index is considered “global” because queries on the index can span all of the data in the base table, across all partitions.

How do you use global secondary index?

You can use the Query operation to access one or more items in a global secondary index. The query must specify the name of the base table and the name of the index that you want to use, the attributes to be returned in the query results, and any query conditions that you want to apply.

What is a sort key DynamoDB?

The sort key of an item is also known as its range attribute. The term range attribute derives from the way DynamoDB stores items with the same partition key physically close together, in sorted order by the sort key value. Each primary key attribute must be a scalar (meaning that it can hold only a single value).

What is DynamoDBMapper?

The DynamoDBMapper class enables you to access your tables; perform various create, read, update, and delete (CRUD) operations; and run queries. The DynamoDBMapper class does not allow you to create, update, or delete tables. To perform those tasks, use the low-level SDK for Java interface instead.

Can you have 10 local secondary indexes on a table?

The data in a local secondary index is organized by the same partition key as the base table, but with a different sort key. This lets you access data items efficiently across this different dimension. For greater query or scan flexibility, you can create up to five local secondary indexes per table.

When can you add a global secondary index to a table?

Global Secondary Indexes (GSI) enable you to perform more efficient queries. Now, you can add or delete GSIs from your table at any time, instead of just during table creation.

How do I create a global secondary index in DynamoDB for an existing table?

To add a global secondary index to an existing table, use the UpdateTable operation with the GlobalSecondaryIndexUpdates parameter. You must provide the following: An index name. The name must be unique among all the indexes on the table.

How many secondary indexes are allowed in DynamoDB?

Each table in DynamoDB can have up to 20 global secondary indexes (default quota) and 5 local secondary indexes.

Can DynamoDB have 2 sort keys?

You can’t have more than 2 fields as primary key in DynamoDB. As a workaround you can create local secondary index for each field that you want to be a range key. But you will not be able to build query with multiple range keys simultaneously because DynamoDB can only use one index at a time.

How do I create a global secondary index in DynamoDB?

DynamoDB does not write item data for a table item with an undefined attribute defined as an index partition or sort key. Create a table with global secondary indexes by using the CreateTable operation paired with the GlobalSecondaryIndexes parameter.

How do I create a table with global secondary indexes?

Create a table with global secondary indexes by using the CreateTable operation paired with the GlobalSecondaryIndexes parameter. You must specify an attribute to serve as the index partition key, or use another for the index sort key. All index key attributes must be string, number, or binary scalars.

What is precipindex in DynamoDB?

The partition key is Location and the sort key is Date. A global secondary index named PrecipIndex allows fast access to precipitation data for various locations. The following are the steps to create a table with a global secondary index, using the DynamoDB document API.

Do the key values in DynamoDB tables need to be unique?

In a DynamoDB table, each key value must be unique. However, the key values in a global secondary index do not need to be unique. To illustrate, suppose that a game named Comet Quest is especially difficult, with many new users trying but failing to get a score above zero. The following is some data that could represent this.