使用 Document API 在 Java 中建立表

在以下示例中，我們將使用 AWS Java SDK for DynamoDB 建立一個名為 Membership 的表。該表將包含代表團隊分配的專案。該表將由 TeamID 分割槽。每個團隊將有多個成員，由 MemberID 標識（作為排序鍵）。

AWSCredentials credentials = new BasicAWSCredentials("access_key", "secret_key");
DynamoDB dynamoDB = new DynamoDB(new AmazonDynamoDBClient(credentials));

try {
      // every DynamoDB table must have basic schema that determines
      //   which attributes are to be used as partition key (and optionally sort key) 
  List<KeySchemaElement> keySchema = new ArrayList<~>();
      // required: specify the partition key (also called hash key)
  keySchema.add(new KeySchemaElement()
             .withAttributeName("TeamID")
             .withKeyType(KeyType.HASH)); 
      // optionally: add a sort key (also called a range key)
  keySchema.add(new KeySchemaElement()
             .withAttributeName("MemberID")
             .withKeyType(KeyType.RANGE));

      // after defining the key schema - the attributes that will be used as partition and range key
      //  we need to specify these attributes' type
  List<AttributeDefinition> attrDefinitions = new ArrayList<~>();
      //  we must specify the type for the TeamID attribute; suppose it's a string
  attrDefinitions.add(new AttributeDefinition()
                  .withAttributeName("TeamID")
                  .withAttributeType("S"));
      //  if using a sort key we need to specify its type; suppose that it's numeric
  attrDefinitions.add(new AttributeDefinition()
                  .withAttributeName("MemberID")
                  .withAttributeType("N"));

        
      // after defining the attributes making up the schema and their type
      // we build a request, specifying the table name and the provisioned capacity 
  CreateTableRequest request = new CreateTableRequest()
      .withTableName("Membership")
      .withKeySchema(keySchema)
      .withAttributeDefinitions(attrDefinitions)
      .withProvisionedThroughput(new ProvisionedThroughput()
           .withReadCapacityUnits(30L)
           .withWriteCapacityUnits(10L));

      // now submit the request to create the table in DynamoDB
  Table table = dynamoDB.createTable(request);

      // creating a table is an asynchronous operation
      // we can wait for the table to be created
  table.waitForActive();

      // the table is now ready and can be used

} catch (Exception e) {
      // the table creation failed. 
      //   the reason for failure may be determined from the exception
}