The following Java code example shows how to work with local secondary indexes in
Amazon DynamoDB. The example creates a table named CustomerOrders
with a
partition key of CustomerId
and a sort key of OrderId
. There
are two local secondary indexes on this table:
-
OrderCreationDateIndex
— The sort key isOrderCreationDate
, and the following attributes are projected into the index:ProductCategory
ProductName
OrderStatus
ShipmentTrackingId
-
IsOpenIndex
— The sort key isIsOpen
, and all of the table attributes are projected into the index.
After the CustomerOrders
table is created, the program loads the table
with data representing customer orders. It then queries the data using the local
secondary indexes. Finally, the program deletes the CustomerOrders
table.
For step-by-step instructions for testing the following sample, see Java code examples.
Example
package com.amazonaws.codesamples.document;
import java.util.ArrayList;
import java.util.Iterator;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder;
import com.amazonaws.services.dynamodbv2.document.DynamoDB;
import com.amazonaws.services.dynamodbv2.document.Index;
import com.amazonaws.services.dynamodbv2.document.Item;
import com.amazonaws.services.dynamodbv2.document.ItemCollection;
import com.amazonaws.services.dynamodbv2.document.PutItemOutcome;
import com.amazonaws.services.dynamodbv2.document.QueryOutcome;
import com.amazonaws.services.dynamodbv2.document.Table;
import com.amazonaws.services.dynamodbv2.document.spec.QuerySpec;
import com.amazonaws.services.dynamodbv2.document.utils.ValueMap;
import com.amazonaws.services.dynamodbv2.model.AttributeDefinition;
import com.amazonaws.services.dynamodbv2.model.CreateTableRequest;
import com.amazonaws.services.dynamodbv2.model.KeySchemaElement;
import com.amazonaws.services.dynamodbv2.model.KeyType;
import com.amazonaws.services.dynamodbv2.model.LocalSecondaryIndex;
import com.amazonaws.services.dynamodbv2.model.Projection;
import com.amazonaws.services.dynamodbv2.model.ProjectionType;
import com.amazonaws.services.dynamodbv2.model.ProvisionedThroughput;
import com.amazonaws.services.dynamodbv2.model.ReturnConsumedCapacity;
import com.amazonaws.services.dynamodbv2.model.Select;
public class DocumentAPILocalSecondaryIndexExample {
static AmazonDynamoDB client = AmazonDynamoDBClientBuilder.standard().build();
static DynamoDB dynamoDB = new DynamoDB(client);
public static String tableName = "CustomerOrders";
public static void main(String[] args) throws Exception {
createTable();
loadData();
query(null);
query("IsOpenIndex");
query("OrderCreationDateIndex");
deleteTable(tableName);
}
public static void createTable() {
CreateTableRequest createTableRequest = new CreateTableRequest().withTableName(tableName)
.withProvisionedThroughput(
new ProvisionedThroughput().withReadCapacityUnits((long) 1)
.withWriteCapacityUnits((long) 1));
// Attribute definitions for table partition and sort keys
ArrayList<AttributeDefinition> attributeDefinitions = new ArrayList<AttributeDefinition>();
attributeDefinitions
.add(new AttributeDefinition().withAttributeName("CustomerId").withAttributeType("S"));
attributeDefinitions.add(new AttributeDefinition().withAttributeName("OrderId").withAttributeType("N"));
// Attribute definition for index primary key attributes
attributeDefinitions
.add(new AttributeDefinition().withAttributeName("OrderCreationDate")
.withAttributeType("N"));
attributeDefinitions.add(new AttributeDefinition().withAttributeName("IsOpen").withAttributeType("N"));
createTableRequest.setAttributeDefinitions(attributeDefinitions);
// Key schema for table
ArrayList<KeySchemaElement> tableKeySchema = new ArrayList<KeySchemaElement>();
tableKeySchema.add(new KeySchemaElement().withAttributeName("CustomerId").withKeyType(KeyType.HASH)); // Partition
// key
tableKeySchema.add(new KeySchemaElement().withAttributeName("OrderId").withKeyType(KeyType.RANGE)); // Sort
// key
createTableRequest.setKeySchema(tableKeySchema);
ArrayList<LocalSecondaryIndex> localSecondaryIndexes = new ArrayList<LocalSecondaryIndex>();
// OrderCreationDateIndex
LocalSecondaryIndex orderCreationDateIndex = new LocalSecondaryIndex()
.withIndexName("OrderCreationDateIndex");
// Key schema for OrderCreationDateIndex
ArrayList<KeySchemaElement> indexKeySchema = new ArrayList<KeySchemaElement>();
indexKeySchema.add(new KeySchemaElement().withAttributeName("CustomerId").withKeyType(KeyType.HASH)); // Partition
// key
indexKeySchema.add(new KeySchemaElement().withAttributeName("OrderCreationDate")
.withKeyType(KeyType.RANGE)); // Sort
// key
orderCreationDateIndex.setKeySchema(indexKeySchema);
// Projection (with list of projected attributes) for
// OrderCreationDateIndex
Projection projection = new Projection().withProjectionType(ProjectionType.INCLUDE);
ArrayList<String> nonKeyAttributes = new ArrayList<String>();
nonKeyAttributes.add("ProductCategory");
nonKeyAttributes.add("ProductName");
projection.setNonKeyAttributes(nonKeyAttributes);
orderCreationDateIndex.setProjection(projection);
localSecondaryIndexes.add(orderCreationDateIndex);
// IsOpenIndex
LocalSecondaryIndex isOpenIndex = new LocalSecondaryIndex().withIndexName("IsOpenIndex");
// Key schema for IsOpenIndex
indexKeySchema = new ArrayList<KeySchemaElement>();
indexKeySchema.add(new KeySchemaElement().withAttributeName("CustomerId").withKeyType(KeyType.HASH)); // Partition
// key
indexKeySchema.add(new KeySchemaElement().withAttributeName("IsOpen").withKeyType(KeyType.RANGE)); // Sort
// key
// Projection (all attributes) for IsOpenIndex
projection = new Projection().withProjectionType(ProjectionType.ALL);
isOpenIndex.setKeySchema(indexKeySchema);
isOpenIndex.setProjection(projection);
localSecondaryIndexes.add(isOpenIndex);
// Add index definitions to CreateTable request
createTableRequest.setLocalSecondaryIndexes(localSecondaryIndexes);
System.out.println("Creating table " + tableName + "...");
System.out.println(dynamoDB.createTable(createTableRequest));
// Wait for table to become active
System.out.println("Waiting for " + tableName + " to become ACTIVE...");
try {
Table table = dynamoDB.getTable(tableName);
table.waitForActive();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public static void query(String indexName) {
Table table = dynamoDB.getTable(tableName);
System.out.println("\n***********************************************************\n");
System.out.println("Querying table " + tableName + "...");
QuerySpec querySpec = new QuerySpec().withConsistentRead(true).withScanIndexForward(true)
.withReturnConsumedCapacity(ReturnConsumedCapacity.TOTAL);
if (indexName == "IsOpenIndex") {
System.out.println("\nUsing index: '" + indexName + "': Bob's orders that are open.");
System.out.println("Only a user-specified list of attributes are returned\n");
Index index = table.getIndex(indexName);
querySpec.withKeyConditionExpression("CustomerId = :v_custid and IsOpen = :v_isopen")
.withValueMap(new ValueMap().withString(":v_custid", "bob@example.com")
.withNumber(":v_isopen", 1));
querySpec.withProjectionExpression(
"OrderCreationDate, ProductCategory, ProductName, OrderStatus");
ItemCollection<QueryOutcome> items = index.query(querySpec);
Iterator<Item> iterator = items.iterator();
System.out.println("Query: printing results...");
while (iterator.hasNext()) {
System.out.println(iterator.next().toJSONPretty());
}
} else if (indexName == "OrderCreationDateIndex") {
System.out.println("\nUsing index: '" + indexName
+ "': Bob's orders that were placed after 01/31/2015.");
System.out.println("Only the projected attributes are returned\n");
Index index = table.getIndex(indexName);
querySpec.withKeyConditionExpression(
"CustomerId = :v_custid and OrderCreationDate >= :v_orddate")
.withValueMap(
new ValueMap().withString(":v_custid", "bob@example.com")
.withNumber(":v_orddate",
20150131));
querySpec.withSelect(Select.ALL_PROJECTED_ATTRIBUTES);
ItemCollection<QueryOutcome> items = index.query(querySpec);
Iterator<Item> iterator = items.iterator();
System.out.println("Query: printing results...");
while (iterator.hasNext()) {
System.out.println(iterator.next().toJSONPretty());
}
} else {
System.out.println("\nNo index: All of Bob's orders, by OrderId:\n");
querySpec.withKeyConditionExpression("CustomerId = :v_custid")
.withValueMap(new ValueMap().withString(":v_custid", "bob@example.com"));
ItemCollection<QueryOutcome> items = table.query(querySpec);
Iterator<Item> iterator = items.iterator();
System.out.println("Query: printing results...");
while (iterator.hasNext()) {
System.out.println(iterator.next().toJSONPretty());
}
}
}
public static void deleteTable(String tableName) {
Table table = dynamoDB.getTable(tableName);
System.out.println("Deleting table " + tableName + "...");
table.delete();
// Wait for table to be deleted
System.out.println("Waiting for " + tableName + " to be deleted...");
try {
table.waitForDelete();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public static void loadData() {
Table table = dynamoDB.getTable(tableName);
System.out.println("Loading data into table " + tableName + "...");
Item item = new Item().withPrimaryKey("CustomerId", "alice@example.com").withNumber("OrderId", 1)
.withNumber("IsOpen", 1).withNumber("OrderCreationDate", 20150101)
.withString("ProductCategory", "Book")
.withString("ProductName", "The Great Outdoors")
.withString("OrderStatus", "PACKING ITEMS");
// no ShipmentTrackingId attribute
PutItemOutcome putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "alice@example.com").withNumber("OrderId", 2)
.withNumber("IsOpen", 1).withNumber("OrderCreationDate", 20150221)
.withString("ProductCategory", "Bike")
.withString("ProductName", "Super Mountain")
.withString("OrderStatus", "ORDER RECEIVED");
// no ShipmentTrackingId attribute
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "alice@example.com").withNumber("OrderId", 3)
// no IsOpen attribute
.withNumber("OrderCreationDate", 20150304).withString("ProductCategory", "Music")
.withString("ProductName", "A Quiet Interlude").withString("OrderStatus", "IN TRANSIT")
.withString("ShipmentTrackingId", "176493");
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "bob@example.com").withNumber("OrderId", 1)
// no IsOpen attribute
.withNumber("OrderCreationDate", 20150111).withString("ProductCategory", "Movie")
.withString("ProductName", "Calm Before The Storm")
.withString("OrderStatus", "SHIPPING DELAY")
.withString("ShipmentTrackingId", "859323");
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "bob@example.com").withNumber("OrderId", 2)
// no IsOpen attribute
.withNumber("OrderCreationDate", 20150124).withString("ProductCategory", "Music")
.withString("ProductName", "E-Z Listening").withString("OrderStatus", "DELIVERED")
.withString("ShipmentTrackingId", "756943");
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "bob@example.com").withNumber("OrderId", 3)
// no IsOpen attribute
.withNumber("OrderCreationDate", 20150221).withString("ProductCategory", "Music")
.withString("ProductName", "Symphony 9").withString("OrderStatus", "DELIVERED")
.withString("ShipmentTrackingId", "645193");
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "bob@example.com").withNumber("OrderId", 4)
.withNumber("IsOpen", 1).withNumber("OrderCreationDate", 20150222)
.withString("ProductCategory", "Hardware")
.withString("ProductName", "Extra Heavy Hammer")
.withString("OrderStatus", "PACKING ITEMS");
// no ShipmentTrackingId attribute
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "bob@example.com").withNumber("OrderId", 5)
/* no IsOpen attribute */
.withNumber("OrderCreationDate", 20150309).withString("ProductCategory", "Book")
.withString("ProductName", "How To Cook").withString("OrderStatus", "IN TRANSIT")
.withString("ShipmentTrackingId", "440185");
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "bob@example.com").withNumber("OrderId", 6)
// no IsOpen attribute
.withNumber("OrderCreationDate", 20150318).withString("ProductCategory", "Luggage")
.withString("ProductName", "Really Big Suitcase").withString("OrderStatus", "DELIVERED")
.withString("ShipmentTrackingId", "893927");
putItemOutcome = table.putItem(item);
item = new Item().withPrimaryKey("CustomerId", "bob@example.com").withNumber("OrderId", 7)
/* no IsOpen attribute */
.withNumber("OrderCreationDate", 20150324).withString("ProductCategory", "Golf")
.withString("ProductName", "PGA Pro II").withString("OrderStatus", "OUT FOR DELIVERY")
.withString("ShipmentTrackingId", "383283");
putItemOutcome = table.putItem(item);
assert putItemOutcome != null;
}
}