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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. For a composite primary key, you must provide both the partition key and the sort key.
Version: (assembly version)
public class KeysAndAttributes : Object
The KeysAndAttributes type exposes the following members
Gets and sets the property AttributesToGet.
One or more attributes to retrieve from the table or index. If no attribute names are specified then all attributes will be returned. If any of the specified attributes are not found, they will not appear in the result.
Gets and sets the property ConsistentRead.
The consistency of a read operation. If set to
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:
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
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:
You could then use this substitution in an expression, as in this example:
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 Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
Gets and sets the property Keys.
The primary key attribute values that define the items and the attributes associated with the items.
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 ProjectionExpression must be separated by commas.
If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.
For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
ProjectionExpression replaces the legacy AttributesToGet parameter.
Supported in: 4.5, 4.0, 3.5
.NET for Windows Store apps:
Supported in: Windows 8.1, Windows 8
.NET for Windows Phone:
Supported in: Windows Phone 8.1, Windows Phone 8