Table of Contents

Class GetItemRequest

Namespace
Amazon.DynamoDBv2.Model
Assembly
AWSSDK.DynamoDBv2.dll

Container for the parameters to the GetItem operation. The 

GetItem
operation returns a set of attributes for the item with the given primary key. If there is no matching item, 
GetItem
does not return any data and there will be no 
Item
element in the response. 

GetItem
provides an eventually consistent read by default. If your application requires a strongly consistent read, set 
ConsistentRead
to 
true
. Although a strongly consistent read might take more time than an eventually consistent read, it always returns the last updated value. 
public class GetItemRequest : AmazonDynamoDBRequest
Inheritance
GetItemRequest

Constructors

GetItemRequest()

Empty constructor used to set properties independently even when a simple constructor is available

public GetItemRequest()

GetItemRequest(string, Dictionary<string, AttributeValue>)

Instantiates GetItemRequest with the parameterized properties

public GetItemRequest(string tableName, Dictionary<string, AttributeValue> key)

Parameters

tableName string

The name of the table containing the requested item.

key Dictionary<string, AttributeValue>

A map of attribute names to 

AttributeValue
objects, representing the primary key of the item to retrieve. For the primary key, you must provide all of the attributes. For example, with a simple primary key, you only need to provide a value for the partition key. For a composite primary key, you must provide values for both the partition key and the sort key.

GetItemRequest(string, Dictionary<string, AttributeValue>, bool)

Instantiates GetItemRequest with the parameterized properties

public GetItemRequest(string tableName, Dictionary<string, AttributeValue> key, bool consistentRead)

Parameters

tableName string

The name of the table containing the requested item.

key Dictionary<string, AttributeValue>

A map of attribute names to 

AttributeValue
objects, representing the primary key of the item to retrieve. For the primary key, you must provide all of the attributes. For example, with a simple primary key, you only need to provide a value for the partition key. For a composite primary key, you must provide values for both the partition key and the sort key.
consistentRead bool

Determines the read consistency model: If set to 

true
, then the operation uses strongly consistent reads; otherwise, the operation uses eventually consistent reads.

Properties

AttributesToGet

Gets and sets the property AttributesToGet.

This is a legacy parameter. Use 

ProjectionExpression
instead. For more information, see AttributesToGet in the Amazon DynamoDB Developer Guide. 
public List<string> AttributesToGet { get; set; }

Property Value

List<string>

ConsistentRead

Gets and sets the property ConsistentRead.

Determines the read consistency model: If set to 

true
, then the operation uses strongly consistent reads; otherwise, the operation uses eventually consistent reads. 
public bool ConsistentRead { get; set; }

Property Value

bool

ExpressionAttributeNames

Gets and sets the property ExpressionAttributeNames.

One or more substitution tokens for attribute names in an expression. The following are some use cases for using 

ExpressionAttributeNames
:

  • To access an attribute whose name conflicts with a DynamoDB reserved word.

  • To create a placeholder for repeating occurrences of an attribute name in an expression.

  • To prevent special characters in an attribute name from being misinterpreted in an expression.

Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name: 

  • Percentile

The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For the complete list of reserved words, see Reserved Words in the Amazon DynamoDB Developer Guide). To work around this, you could specify the following for 

ExpressionAttributeNames
: 

  • {"#P":"Percentile"}

You could then use this substitution in an expression, as in this example: 

  • #P = :val
note

Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.

For more information on expression attribute names, see Specifying Item Attributes in the Amazon DynamoDB Developer Guide. 

public Dictionary<string, string> ExpressionAttributeNames { get; set; }

Property Value

Dictionary<string, string>

Key

Gets and sets the property Key.

A map of attribute names to 

AttributeValue
objects, representing the primary key of the item to retrieve.

For the primary key, you must provide all of the attributes. For example, with a simple primary key, you only need to provide a value for the partition key. For a composite primary key, you must provide values for both the partition key and the sort key. 

public Dictionary<string, AttributeValue> Key { get; set; }

Property Value

Dictionary<string, AttributeValue>

ProjectionExpression

Gets and sets the property ProjectionExpression.

A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, sets, or elements of a JSON document. The attributes in the expression must be separated by commas.

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

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

public string ProjectionExpression { get; set; }

Property Value

string

ReturnConsumedCapacity

Gets and sets the property ReturnConsumedCapacity.

public ReturnConsumedCapacity ReturnConsumedCapacity { get; set; }

Property Value

ReturnConsumedCapacity

TableName

Gets and sets the property TableName.

The name of the table containing the requested item. 

public string TableName { get; set; }

Property Value

string