It is not possible to remove TableNamePrefix via DynamoDBOperationConfig

[Dreamescaper]

Describe the bug

	        [DynamoDBTable("test-table")]
	        class ExternalTable
	        {
				...
	        }

            var dynamoDbContext = new DynamoDBContext(new DynamoDBContextConfig
            {
                TableNamePrefix = "my-prefix-"
            });

            dynamoDbContext.SaveAsync(new ExternalTable { }, new DynamoDBOperationConfig
            {
                TableNamePrefix = "",
                OverrideTableName = "external-table"
            });

Expected Behavior

Since I have explicitly set TableNamePrefix to empty string, I would expect it to be empty, there SaveAsync would happen for "external-table" table name.

Current Behavior

TableNamePrefix = "" is ignored. SaveAsync is attempted for "my-prefix-external-table" table name.

Possible Solution

Create a separate context.

Additional Information/Context

DynamoDBFlatConfig uses string.IsNullOrEmpty comparison, therefore empty string is simply ignored.

AWS .NET SDK and/or Package version used

3.7.402.7

Targeted .NET Platform

.NET 8

Operating System and version

AmazonLinux

[bhoradc]

Hello @Dreamescaper,

Thank you for reporting the issue. As per the source code, if the DynamoDBOperationConfig.TableNamePrefix is Empty it falls back to the DynamoDBContextConfig.TableNamePrefix which is set to "my-prefix-" in your case.

Ideally DynamoDBOperationConfig would override any settings specified by the DynamoDBContextConfig object. But due to above logic, I don’t see a way to remove the TableNamePrefix from inside DynamoDBOperationConfig if its set (Non Empty or not null) in DynamoDBContextConfig.

I will further check on this with the team and keep you posted.

Repro code

Package version: AWSSDK.DynamoDBv2 3.7.400.18

       static async Task Main(string[] args)
       {
           //Create DDB table=`my-prefix-external-table` and Partition key as id(String)

           var client = new AmazonDynamoDBClient();

           var config = new DynamoDBContextConfig
           {
               TableNamePrefix = "my-prefix-"
           };

           var dynamoDbContext = new DynamoDBContext(client, config);

           await dynamoDbContext.SaveAsync(new ExternalTable { Id = "1" }, new DynamoDBOperationConfig
           {
               TableNamePrefix = "",
               OverrideTableName = "external-table"
           });
       }

       [DynamoDBTable("test-table")]
       public class ExternalTable
       {
           [DynamoDBHashKey]
           [DynamoDBProperty("id")]
           public string Id { get; set; } = null!;
       }

Regards,
Chaitanya

[Dreamescaper]

I assume that technically, changing that behavior would be a breaking change.
Would it make sense to fix it in V4 for new operation-specific overloads?

[bhoradc]

Hello @Dreamescaper,

Team will be fixing this issue as part of V4 efforts. Thank you again for reporting the issue.

Regards,
Chaitanya