.net通过DynamoDBContext查询DynamoDB中的全局二级索引

Question

我有一个dynamoDB表,其架构如下:

var request = new CreateTableRequest
{
    TableName = tableName,
    KeySchema = new List<KeySchemaElement>
    {
        new KeySchemaElement("CompanyId", KeyType.HASH),
        new KeySchemaElement("Timestamp", KeyType.RANGE)
    },
    AttributeDefinitions = new List<AttributeDefinition>
    {
        new AttributeDefinition("CompanyId", ScalarAttributeType.S),
        new AttributeDefinition("Timestamp", ScalarAttributeType.N),
        new AttributeDefinition("UserId", ScalarAttributeType.S)
    },
    GlobalSecondaryIndexes = new List<GlobalSecondaryIndex>
    {
        new GlobalSecondaryIndex
        {
            IndexName = "UserIndex",
            KeySchema = new List<KeySchemaElement>
            {
                new KeySchemaElement("UserId", KeyType.HASH),
                new KeySchemaElement("Timestamp", KeyType.RANGE)
            },
            Projection = new Projection {ProjectionType = "ALL"},
            ProvisionedThroughput = new ProvisionedThroughput(5, 6)
        }
    },
    ProvisionedThroughput = new ProvisionedThroughput(5, 6)
};

我可以成功查询主键,如下所示:

var client = new AmazonDynamoDBClient();
using (var context = new DynamoDBContext(client))
{
    var sortKeyValues = new List<object>{minTimestamp};
    result = await context.QueryAsync<AuditLogEntry>(companyId, QueryOperator.GreaterThanOrEqual, sortKeyValues,
                            new DynamoDBOperationConfig {OverrideTableName = TableName}).GetRemainingAsync();
}

我可以查询全局二级索引,而不对范围键有任何约束,如下所示:

var client = new AmazonDynamoDBClient();
using (var context = new DynamoDBContext(client))
{
    result = await context.QueryAsync<AuditLogEntry>(userId, new DynamoDBOperationConfig {OverrideTableName = TableName, IndexName = indexName})
        .GetRemainingAsync();
}

但是当我尝试使用范围键约束查询索引时:

var client = new AmazonDynamoDBClient();
using (var context = new DynamoDBContext(client))
{
    var sortKeyValues = new List<object> {minTimestamp};
    result = await context.QueryAsync<AuditLogEntry>(userId, QueryOperator.GreaterThan, sortKeyValues, new DynamoDBOperationConfig {OverrideTableName = TableName, IndexName = indexName}).GetRemainingAsync();
}

我收到以下错误:

Exception thrown: 'System.InvalidOperationException' in AWSSDK.DynamoDBv2.dll

Additional information: Local Secondary Index range key conditions are used but no index could be inferred from model. Specified index name = UserIndex

谷歌搜索这个错误并没有对这个问题有任何启发.对本地二级索引的引用让我感到困惑,因为我使用的是全局索引,但我看不出我的代码有什么问题.

我已经能够通过直接在AmazonDynamoDBClient上查询而不是使用DynamoDBContext来查询查询,但我真的很想了解我做错了什么并且能够使用DynamoDBContext.

任何想法,将不胜感激.

Answer 1

在 AuditLogEntry 的模型定义中，您需要使用属性 - [DynamoDBGlobalSecondaryIndexRangeKey] 和/或 [DynamoDBGlobalSecondaryIndexHashKey] 来装饰属于全局二级索引的属性。下面的例子。

public class AuditLogEntry {
    // other properties ...
    
    [DynamoDBProperty("UserId")]
    [DynamoDBGlobalSecondaryIndexHashKey("UserIndex")]
    public string UserId { get; set; }
}