Struct rusoto_dynamodb::BatchGetItemInput
source · [−]pub struct BatchGetItemInput {
pub request_items: HashMap<String, KeysAndAttributes>,
pub return_consumed_capacity: Option<String>,
}
Expand description
Represents the input of a BatchGetItem
operation.
Fields
request_items: HashMap<String, KeysAndAttributes>
A map of one or more table names and, for each table, a map that describes one or more items to retrieve from that table. Each table name can be used only once per BatchGetItem
request.
Each element in the map of items to retrieve consists of the following:
-
ConsistentRead
- Iftrue
, a strongly consistent read is used; iffalse
(the default), an eventually consistent read is used. -
ExpressionAttributeNames
- One or more substitution tokens for attribute names in theProjectionExpression
parameter. The following are some use cases for usingExpressionAttributeNames
:-
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 about expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
-
-
Keys
- An array of primary key attribute values that define specific items in the table. For each primary key, you must provide all of the key attributes. For example, with a simple primary key, you only need to provide the partition key value. For a composite key, you must provide both the partition key value and the sort key value. -
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 Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
-
AttributesToGet
- This is a legacy parameter. UseProjectionExpression
instead. For more information, see AttributesToGet in the Amazon DynamoDB Developer Guide.
return_consumed_capacity: Option<String>
Trait Implementations
sourceimpl Clone for BatchGetItemInput
impl Clone for BatchGetItemInput
sourcefn clone(&self) -> BatchGetItemInput
fn clone(&self) -> BatchGetItemInput
Returns a copy of the value. Read more
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source
. Read more
sourceimpl Debug for BatchGetItemInput
impl Debug for BatchGetItemInput
sourceimpl Default for BatchGetItemInput
impl Default for BatchGetItemInput
sourcefn default() -> BatchGetItemInput
fn default() -> BatchGetItemInput
Returns the “default value” for a type. Read more
sourceimpl PartialEq<BatchGetItemInput> for BatchGetItemInput
impl PartialEq<BatchGetItemInput> for BatchGetItemInput
sourcefn eq(&self, other: &BatchGetItemInput) -> bool
fn eq(&self, other: &BatchGetItemInput) -> bool
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
sourcefn ne(&self, other: &BatchGetItemInput) -> bool
fn ne(&self, other: &BatchGetItemInput) -> bool
This method tests for !=
.
sourceimpl Serialize for BatchGetItemInput
impl Serialize for BatchGetItemInput
impl StructuralPartialEq for BatchGetItemInput
Auto Trait Implementations
impl RefUnwindSafe for BatchGetItemInput
impl Send for BatchGetItemInput
impl Sync for BatchGetItemInput
impl Unpin for BatchGetItemInput
impl UnwindSafe for BatchGetItemInput
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<T> Instrument for T
impl<T> Instrument for T
sourcefn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
sourcefn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
sourceimpl<T> ToOwned for T where
T: Clone,
impl<T> ToOwned for T where
T: Clone,
type Owned = T
type Owned = T
The resulting type after obtaining ownership.
sourcefn clone_into(&self, target: &mut T)
fn clone_into(&self, target: &mut T)
toowned_clone_into
)Uses borrowed data to replace owned data, usually by cloning. Read more
sourceimpl<T> WithSubscriber for T
impl<T> WithSubscriber for T
sourcefn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
sourcefn with_current_subscriber(self) -> WithDispatch<Self>
fn with_current_subscriber(self) -> WithDispatch<Self>
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more