Struct aws_sdk_dynamodb::input::GetItemInput [−][src]
#[non_exhaustive]pub struct GetItemInput {
pub table_name: Option<String>,
pub key: Option<HashMap<String, AttributeValue>>,
pub attributes_to_get: Option<Vec<String>>,
pub consistent_read: Option<bool>,
pub return_consumed_capacity: Option<ReturnConsumedCapacity>,
pub projection_expression: Option<String>,
pub expression_attribute_names: Option<HashMap<String, String>>,
}
Expand description
Represents the input of a GetItem
operation.
Fields (Non-exhaustive)
This struct is marked as non-exhaustive
Struct { .. }
syntax; cannot be matched against without a wildcard ..
; and struct update syntax will not work.table_name: Option<String>
The name of the table containing the requested item.
key: Option<HashMap<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.
attributes_to_get: Option<Vec<String>>
This is a legacy parameter. Use ProjectionExpression
instead. For more information, see
AttributesToGet in the Amazon DynamoDB Developer Guide.
consistent_read: Option<bool>
Determines the read consistency model: If set to true
, then the operation uses strongly consistent reads; otherwise, the operation uses eventually consistent reads.
return_consumed_capacity: Option<ReturnConsumedCapacity>
Determines the level of detail about provisioned throughput consumption that is returned in the response:
-
INDEXES
- The response includes the aggregateConsumedCapacity
for the operation, together withConsumedCapacity
for each table and secondary index that was accessed.Note that some operations, such as
GetItem
andBatchGetItem
, do not access any indexes at all. In these cases, specifyingINDEXES
will only returnConsumedCapacity
information for table(s). -
TOTAL
- The response includes only the aggregateConsumedCapacity
for the operation. -
NONE
- NoConsumedCapacity
details are included in the response.
projection_expression: Option<String>
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.
expression_attribute_names: Option<HashMap<String, String>>
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
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.
Implementations
pub async fn make_operation(
&self,
_config: &Config
) -> Result<Operation<GetItem, AwsErrorRetryPolicy>, BuildError>
pub async fn make_operation(
&self,
_config: &Config
) -> Result<Operation<GetItem, AwsErrorRetryPolicy>, BuildError>
Consumes the builder and constructs an Operation<GetItem
>
Creates a new builder-style object to manufacture GetItemInput
Trait Implementations
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
This method tests for !=
.
Auto Trait Implementations
impl RefUnwindSafe for GetItemInput
impl Send for GetItemInput
impl Sync for GetItemInput
impl Unpin for GetItemInput
impl UnwindSafe for GetItemInput
Blanket Implementations
Mutably borrows from an owned value. Read more
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more