DYNDB121: Duplicate GSI partition keys

Field	Value
Code	DYNDB121
Severity	Error

Message

GSI '{0}' on entity '{1}' has multiple partition keys: properties '{2}' and '{3}'. Only one is allowed.

Description

A Global Secondary Index can only have one partition key property. Remove the duplicate [GsiPartitionKey] attribute from one of the properties. DynamoDB indexes support exactly one partition key attribute.

Example

The following code triggers this diagnostic:

[DynamoDbTable("Orders")]
public partial class Order
{
    [PartitionKey]
    [DynamoDbAttribute("pk")]
    public string Pk { get; set; } = string.Empty;

    [GsiPartitionKey("status-index")]
    [DynamoDbAttribute("status")]
    public string Status { get; set; } = string.Empty;

    [GsiPartitionKey("status-index")]
    [DynamoDbAttribute("category")]
    public string Category { get; set; } = string.Empty;
}

Fix

The corrected version:

[DynamoDbTable("Orders")]
public partial class Order
{
    [PartitionKey]
    [DynamoDbAttribute("pk")]
    public string Pk { get; set; } = string.Empty;

    [GsiPartitionKey("status-index")]
    [DynamoDbAttribute("status")]
    public string Status { get; set; } = string.Empty;

    [GsiSortKey("status-index")]
    [DynamoDbAttribute("category")]
    public string Category { get; set; } = string.Empty;
}