Package software.amazon.awssdk.enhanced.dynamodb.model

Class ScanEnhancedRequest.Builder

    • Method Detail

      • exclusiveStartKey

        public ScanEnhancedRequest.Builder exclusiveStartKey​(Map<String,​AttributeValue> exclusiveStartKey)
        The primary key of the first item that this operation will evaluate. By default, the operation will evaluate the whole dataset. If used, normally this parameter is populated with the value that was returned for Page.lastEvaluatedKey() in the previous operation.
        Parameters:
        exclusiveStartKey - the primary key value where DynamoDb should start to evaluate items
        Returns:
        a builder of this type

      • limit

        public ScanEnhancedRequest.Builder limit​(Integer limit)
        Sets a limit on how many items to evaluate in the scan. If not set, the operation uses the maximum values allowed.

        Note:The limit does not refer to the number of items to return, but how many items the database should evaluate while executing the scan. Use limit together with Page.lastEvaluatedKey() and exclusiveStartKey in subsequent scan calls to evaluate limit items per call.

        Parameters:
        limit - the maximum number of items to evalute
        Returns:
        a builder of this type

      • segment

        public ScanEnhancedRequest.Builder segment​(Integer segment)
        For a parallel Scan request, Segment identifies an individual segment to be scanned by an application worker.

        Note:Segment IDs are zero-based, so the first segment is always 0. For example, if you want to use four application threads to scan a table or an index, then the first thread specifies a Segment value of 0, the second thread specifies 1, and so on. The value for Segment must be greater than or equal to 0, and less than the value provided for TotalSegments. If you provide Segment, you must also provide TotalSegments.

        Parameters:
        segment - identifies an individual segment to be scanned
        Returns:
        a builder of this type

      • totalSegments

        public ScanEnhancedRequest.Builder totalSegments​(Integer totalSegments)
        For a parallel Scan request, TotalSegments represents the total number of segments into which the Scan operation will be divided.

        Note:If you do not specify this value, the TotalSegements is effectively 1 and Scan operation will be sequential rather than parallel. If you specify TotalSegments, you must also specify Segment. If you specify TotalSegments of 2 and above, you can create separate thread for each segment and scan items in parallel across segments from multiple threads.

        Parameters:
        totalSegments - the total number of segments to divide the table.
        Returns:
        a builder of this type

      • consistentRead

        public ScanEnhancedRequest.Builder consistentRead​(Boolean consistentRead)
        Determines the read consistency model: If set to true, the operation uses strongly consistent reads; otherwise, the operation uses eventually consistent reads.

        By default, the value of this property is set to false.

        Parameters:
        consistentRead - sets consistency model of the operation to use strong consistency if true
        Returns:
        a builder of this type

      • filterExpression

        public ScanEnhancedRequest.Builder filterExpression​(Expression filterExpression)
        Refines the scan results by applying the filter expression on the results returned from the scan and discards items that do not match. See Expression for examples and constraints.

        Note: Using the filter expression does not reduce the cost of the scan, since it is applied after the database has found matching items.

        Parameters:
        filterExpression - an expression that filters results of evaluating the scan
        Returns:
        a builder of this type

      • select

        public ScanEnhancedRequest.Builder select​(Select select)
        Determines the attributes to be returned in the result. See Select for examples and constraints. By default, all attributes are returned.
        Parameters:
        select -
        Returns:
        a builder of this type

      • attributesToProject

        public ScanEnhancedRequest.Builder attributesToProject​(Collection<String> attributesToProject)

        Sets a collection of the attribute names to be retrieved from the database. These attributes can include scalars, sets, or elements of a JSON document.

        If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.

        If there are nested attributes, use any of the addNestedAttributesToProject methods, such as addNestedAttributesToProject(NestedAttributeName...).

        For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.

        Parameters:
        attributesToProject - A collection of the attributes names to be retrieved from the database.
        Returns:
        Returns a reference to this object so that method calls can be chained together.

      • attributesToProject

        public ScanEnhancedRequest.Builder attributesToProject​(String... attributesToProject)

        Sets one or more attribute names to be retrieved from the database. These attributes can include scalars, sets, or elements of a JSON document.

        If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.

        If there are nested attributes, use any of the addNestedAttributesToProject methods, such as addNestedAttributesToProject(NestedAttributeName...).

        For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.

        Parameters:
        attributesToProject - One or more attributes names to be retrieved from the database.
        Returns:
        Returns a reference to this object so that method calls can be chained together.

      • addAttributeToProject

        public ScanEnhancedRequest.Builder addAttributeToProject​(String attributeToProject)

        Adds a single attribute name to be retrieved from the database. This attribute can include scalars, sets, or elements of a JSON document.

        If there are nested attributes, use any of the addNestedAttributesToProject methods, such as addNestedAttributesToProject(NestedAttributeName...).

        Parameters:
        attributeToProject - An additional single attribute name to be retrieved from the database.
        Returns:
        Returns a reference to this object so that method calls can be chained together.

      • addNestedAttributesToProject

        public ScanEnhancedRequest.Builder addNestedAttributesToProject​(Collection<NestedAttributeName> nestedAttributeNames)
        Adds a collection of nested attributes to be retrieved from the database. These attributes can include scalars, sets, or elements of a JSON document.

        This method is additive, so calling it multiple times will add to the list of nested attribute names.

        Parameters:
        nestedAttributeNames - A collection of attributes to be retrieved from the database.
        Returns:
        Returns a reference to this object so that method calls can be chained together.
        See Also:
        NestedAttributeName

      • addNestedAttributesToProject

        public ScanEnhancedRequest.Builder addNestedAttributesToProject​(NestedAttributeName... nestedAttributeNames)
        Adds a collection of nested attributes to be retrieved from the database. These attributes can include scalars, sets, or elements of a JSON document.

        This method is additive, so calling it multiple times will add to the list of nested attribute names.

        Parameters:
        nestedAttributeNames - A collection of attributes to be retrieved from the database.
        Returns:
        Returns a reference to this object so that method calls can be chained together.
        See Also:
        NestedAttributeName

      • addNestedAttributeToProject

        public ScanEnhancedRequest.Builder addNestedAttributeToProject​(NestedAttributeName nestedAttributeName)
        Adds a single nested attribute to be retrieved from the database. The attribute can include scalars, sets, or elements of a JSON document.

        This method is additive, so calling it multiple times will add to the list of nested attribute names.

        Parameters:
        nestedAttributeName - A single attribute name to be retrieved from the database.
        Returns:
        Returns a reference to this object so that method calls can be chained together.
        See Also:
        NestedAttributeName