Is DynamoDB asynchronous?

The following is an example of an asynchronous operation that calls a Amazon DynamoDB function to get a list of tables, receiving a CompletableFuture that can hold a ListTablesResponse object.

Is DynamoDB eventually consistent?

DynamoDB uses eventually consistent reads, unless you specify otherwise. Read operations (such as GetItem , Query , and Scan ) provide a ConsistentRead parameter. If you set this parameter to true, DynamoDB uses strongly consistent reads during the operation.

What is DynamoDBMapper?

The DynamoDBMapper class is the entry point to Amazon DynamoDB. It provides access to a DynamoDB endpoint and enables you to access your data in various tables. It also enables you to perform various create, read, update, and delete (CRUD) operations on items, and run queries and scans against tables.

Is DynamoDB transactional?

DynamoDB performs two underlying reads or writes of every item in the transaction: one to prepare the transaction and one to commit the transaction. The two underlying read/write operations are visible in your Amazon CloudWatch metrics.

Is DynamoDB immutable?

Introducing immutable class mapping for the Enhanced DynamoDB Client in AWS SDK for Java 2. x. We are pleased to announce that the enhanced DynamoDB client in the AWS SDK for Java 2. x now supports the mapping of immutable Java objects directly with records in your DynamoDB tables.

How does DynamoDB stream work?

DynamoDB Streams captures a time-ordered sequence of item-level modifications in any DynamoDB table and stores this information in a log for up to 24 hours. Applications can access this log and view the data items as they appeared before and after they were modified, in near-real time.

When should you not use DynamoDB?

When not to use DynamoDB:

  1. When multi-item or cross table transactions are required.
  2. When complex queries and joins are required.
  3. When real-time analytics on historic data is required.

How does DynamoDB achieve strong consistency?

Strong Consistency While the DynamoDB table supports strongly consistent reading, it results after all mutations have been fully activated. Therefore, this model will guarantee the return of the most updated data. The process behind this behavior is by locking down the physical nodes as they update.

What is DynamoDBIndexHashKey?

Annotation Type DynamoDBIndexHashKey Annotation for marking a property in a class as the attribute to be used as the hash key for one or more global secondary indexes on a DynamoDB table. Applied to the getter method or the class field for the index hash key property.

Is DynamoDB good for transactional?

Amazon DynamoDB transactions simplify the developer experience of making coordinated, all-or-nothing changes to multiple items both within and across tables. Transactions provide atomicity, consistency, isolation, and durability (ACID) in DynamoDB, helping you to maintain data correctness in your applications.

Is DynamoDB relational?

Instead of the relational model, NoSQL databases (like DynamoDB) use alternate models for data management, such as key-value pairs or document storage. It is common for web-based applications to have hundreds, thousands, or millions of concurrent users, with terabytes or more of new data generated per day.