Package software.amazon.awssdk.enhanced.dynamodb

Interface DynamoDbIndex<T>

  • Type Parameters:
    T - The type of the modelled object.
    All Known Implementing Classes:
    DefaultDynamoDbIndex
    @ThreadSafe
public interface DynamoDbIndex<T>
    Synchronous interface for running commands against an object that is linked to a specific DynamoDb secondary index and knows how to map records from the table that index is linked to into a modelled object.

    By default, all command methods throw an UnsupportedOperationException to prevent interface extensions from breaking implementing classes.

    • Method Detail

      • query

        default SdkIterable<Page<T>> query​(QueryEnhancedRequest request)
        Executes a query against a secondary index using a QueryConditional expression to retrieve a list of items matching the given conditions.

        The result is accessed through iterable pages (see Page) in an interactive way; each time a result page is retrieved, a query call is made to DynamoDb to get those entries. If no matches are found, the resulting iterator will contain an empty page. Results are sorted by sort key value in ascending order by default; this behavior can be overridden in the QueryEnhancedRequest.

        The additional configuration parameters that the enhanced client supports are defined in the QueryEnhancedRequest.

        This operation calls the low-level DynamoDB API Query operation. Consult the Query documentation for further details and constraints.

        Example: 

         

 QueryConditional queryConditional = QueryConditional.keyEqualTo(Key.builder().partitionValue("id-value").build());
 Iterator<Page<MyItem>> results = mappedIndex.query(QueryEnhancedRequest.builder()
                                                                        .queryConditional(queryConditional)
                                                                        .build());
        Parameters:
        request - A QueryEnhancedRequest defining the query conditions and how to handle the results.
        Returns:
        an iterator of type SdkIterable with paginated results (see Page).

      • query

        default SdkIterable<Page<T>> query​(Consumer<QueryEnhancedRequest.Builder> requestConsumer)
        Executes a query against a secondary index using a QueryConditional expression to retrieve a list of items matching the given conditions.

        The result is accessed through iterable pages (see Page) in an interactive way; each time a result page is retrieved, a query call is made to DynamoDb to get those entries. If no matches are found, the resulting iterator will contain an empty page. Results are sorted by sort key value in ascending order by default; this behavior can be overridden in the QueryEnhancedRequest.

        The additional configuration parameters that the enhanced client supports are defined in the QueryEnhancedRequest.

        This operation calls the low-level DynamoDB API Query operation. Consult the Query documentation for further details and constraints.

        Note: This is a convenience method that creates an instance of the request builder avoiding the need to create one manually via QueryEnhancedRequest.builder().

        Example: 

         

 Iterator<Page<MyItem>> results =
     mappedIndex.query(r -> r.queryConditional(QueryConditional.keyEqualTo(k -> k.partitionValue("id-value"))));
        Parameters:
        requestConsumer - A Consumer of QueryEnhancedRequest defining the query conditions and how to handle the results.
        Returns:
        an iterator of type SdkIterable with paginated results (see Page).

      • query

        default SdkIterable<Page<T>> query​(QueryConditional queryConditional)
        Executes a query against the secondary index of the table using a QueryConditional expression to retrieve a list of items matching the given conditions.

        The result is accessed through iterable pages (see Page) in an interactive way; each time a result page is retrieved, a query call is made to DynamoDb to get those entries. If no matches are found, the resulting iterator will contain an empty page. Results are sorted by sort key value in ascending order.

        This operation calls the low-level DynamoDB API Query operation. Consult the Query documentation for further details and constraints.

        Example: 

         

 Iterator<Page<MyItem>> results =
     mappedIndex.query(QueryConditional.keyEqualTo(Key.builder().partitionValue("id-value").build()));
        Parameters:
        queryConditional - A QueryConditional defining the matching criteria for records to be queried.
        Returns:
        an iterator of type SdkIterable with paginated results (see Page).

      • scan

        default SdkIterable<Page<T>> scan​(ScanEnhancedRequest request)
        Scans the table against a secondary index and retrieves all items.

        The result is accessed through iterable pages (see Page) in an interactive way; each time a result page is retrieved, a scan call is made to DynamoDb to get those entries. If no matches are found, the resulting iterator will contain an empty page.

        The additional configuration parameters that the enhanced client supports are defined in the ScanEnhancedRequest.

        Example: 

         

 Iterator<Page<MyItem>> results = mappedTable.scan(ScanEnhancedRequest.builder().consistentRead(true).build());
        Parameters:
        request - A ScanEnhancedRequest defining how to handle the results.
        Returns:
        an iterator of type SdkIterable with paginated results (see Page).

      • scan

        default SdkIterable<Page<T>> scan​(Consumer<ScanEnhancedRequest.Builder> requestConsumer)
        Scans the table against a secondary index and retrieves all items.

        The result is accessed through iterable pages (see Page) in an interactive way; each time a result page is retrieved, a scan call is made to DynamoDb to get those entries. If no matches are found, the resulting iterator will contain an empty page.

        The additional configuration parameters that the enhanced client supports are defined in the ScanEnhancedRequest.

        Note: This is a convenience method that creates an instance of the request builder avoiding the need to create one manually via ScanEnhancedRequest.builder().

        Example: 

         

 Iterator<Page<MyItem>> results = mappedTable.scan(r -> r.limit(5));
        Parameters:
        requestConsumer - A Consumer of ScanEnhancedRequest defining the query conditions and how to handle the results.
        Returns:
        an iterator of type SdkIterable with paginated results (see Page).

      • scan

        default SdkIterable<Page<T>> scan()
        Scans the table against a secondary index and retrieves all items using default settings.

        The result is accessed through iterable pages (see Page) in an interactive way; each time a result page is retrieved, a scan call is made to DynamoDb to get those entries. If no matches are found, the resulting iterator will contain an empty page.

        Example: 

         

 Iterator<Page<MyItem>> results = mappedTable.scan();
        Returns:
        an iterator of type SdkIterable with paginated results (see Page).

      • tableName

        String tableName()
        Gets the physical table name that operations performed by this object will be executed against.
        Returns:
        The physical table name.

      • indexName

        String indexName()
        Gets the physical secondary index name that operations performed by this object will be executed against.
        Returns:
        The physical secondary index name.

      • keyFrom

        Key keyFrom​(T item)
        Creates a Key object from a modelled item. This key can be used in query conditionals and get operations to locate a specific record.
        Parameters:
        item - The item to extract the key fields from.
        Returns:
        A key that has been initialized with the index values extracted from the modelled object.