class Aws::DynamoDB::Types::GetItemInput

Represents the input of a `GetItem` operation.

@note When making an API call, you may pass GetItemInput

data as a hash:

    {
      table_name: "TableName", # required
      key: { # required
        "AttributeName" => "value", # value <Hash,Array,String,Numeric,Boolean,IO,Set,nil>
      },
      attributes_to_get: ["AttributeName"],
      consistent_read: false,
      return_consumed_capacity: "INDEXES", # accepts INDEXES, TOTAL, NONE
      projection_expression: "ProjectionExpression",
      expression_attribute_names: {
        "ExpressionAttributeNameVariable" => "AttributeName",
      },
    }

@!attribute [rw] table_name

The name of the table containing the requested item.
@return [String]

@!attribute [rw] 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.
@return [Hash<String,Types::AttributeValue>]

@!attribute [rw] attributes_to_get

This is a legacy parameter. Use `ProjectionExpression` instead. For
more information, see [AttributesToGet][1] in the *Amazon DynamoDB
Developer Guide*.

[1]: https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.AttributesToGet.html
@return [Array<String>]

@!attribute [rw] consistent_read

Determines the read consistency model: If set to `true`, then the
operation uses strongly consistent reads; otherwise, the operation
uses eventually consistent reads.
@return [Boolean]

@!attribute [rw] return_consumed_capacity

Determines the level of detail about provisioned throughput
consumption that is returned in the response:

* `INDEXES` - The response includes the aggregate `ConsumedCapacity`
  for the operation, together with `ConsumedCapacity` for each table
  and secondary index that was accessed.

  Note that some operations, such as `GetItem` and `BatchGetItem`,
  do not access any indexes at all. In these cases, specifying
  `INDEXES` will only return `ConsumedCapacity` information for
  table(s).

* `TOTAL` - The response includes only the aggregate
  `ConsumedCapacity` for the operation.

* `NONE` - No `ConsumedCapacity` details are included in the
  response.
@return [String]

@!attribute [rw] projection_expression

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][1] in the
*Amazon DynamoDB Developer Guide*.

[1]: https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html
@return [String]

@!attribute [rw] expression_attribute_names

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][1] 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 markdown="1"> Tokens that begin with the **\:** character are *expression
attribute values*, which are placeholders for the actual value at
runtime.

 </note>

For more information on expression attribute names, see [Specifying
Item Attributes][2] in the *Amazon DynamoDB Developer Guide*.

[1]: https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html
[2]: https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html
@return [Hash<String,String>]

@see docs.aws.amazon.com/goto/WebAPI/dynamodb-2012-08-10/GetItemInput AWS API Documentation

Constants

SENSITIVE