AWS SDK for .NET Documentation
KeySchema Property
AmazonAmazon.DynamoDBv2.ModelGlobalSecondaryIndexKeySchema Did this page help you?   Yes   No    Tell us about it...
The complete key schema for a global secondary index, which consists of one or more pairs of attribute names and key types (HASH or RANGE).

Constraints:

Length
1 - 2

Declaration Syntax
C#
public List<KeySchemaElement> KeySchema { get; set; }

Assembly: AWSSDK (Module: AWSSDK) Version: 1.5.60.0 (1.5.60.0)