The batch_get_item operation returns the attributes of one or more items from one or more tables. You identify requested items by primary key.
See https://www.paws-r-sdk.com/docs/dynamodb_batch_get_item/ for full documentation.
dynamodb_batch_get_item(RequestItems, ReturnConsumedCapacity = NULL)[required] A map of one or more table names or table ARNs and, for each table, a
map that describes one or more items to retrieve from that table. Each
table name or ARN can be used only once per
batch_get_item request.
Each element in the map of items to retrieve consists of the following:
ConsistentRead - If true, a strongly consistent read is used; if
false (the default), an eventually consistent read is used.
ExpressionAttributeNames - One or more substitution tokens for
attribute names in the ProjectionExpression parameter. 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 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. Use
ProjectionExpression instead. For more information, see
AttributesToGet
in the Amazon DynamoDB Developer Guide.