AWS SDK Version 3 for .NET
API Reference

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Edits an existing item's attributes, or adds a new item to the table if it does not already exist. You can put, delete, or add attribute values. You can also perform a conditional update on an existing item (insert a new attribute name-value pair if it doesn't exist, or replace an existing name-value pair if it has certain expected attribute values).

You can also return the item's attribute values in the same UpdateItem operation using the ReturnValues parameter.


For .NET Core, PCL and Unity this operation is only available in asynchronous form. Please refer to UpdateItemAsync.

Namespace: Amazon.DynamoDBv2
Assembly: AWSSDK.DynamoDBv2.dll
Version: 3.x.y.z


public abstract UpdateItemResponse UpdateItem(
         String tableName,
         Dictionary<String, AttributeValue> key,
         Dictionary<String, AttributeValueUpdate> attributeUpdates,
         ReturnValue returnValues
Type: System.String

The name of the table containing the item to update.

Type: System.Collections.Generic.Dictionary<System.String, Amazon.DynamoDBv2.Model.AttributeValue>

The primary key of the item to be updated. Each element consists of an attribute name and a value for that attribute. For the primary key, you must provide all of the attributes. For example, with a simple primary key, you only need to provide a value for the partition key. For a composite primary key, you must provide values for both the partition key and the sort key.

Type: System.Collections.Generic.Dictionary<System.String, Amazon.DynamoDBv2.Model.AttributeValueUpdate>

This is a legacy parameter. Use UpdateExpression instead. For more information, see AttributeUpdates in the Amazon DynamoDB Developer Guide.

Type: Amazon.DynamoDBv2.ReturnValue

Use ReturnValues if you want to get the item attributes as they appear before or after they are updated. For UpdateItem, the valid values are: NONE - If ReturnValues is not specified, or if its value is NONE, then nothing is returned. (This setting is the default for ReturnValues.) ALL_OLD - Returns all of the attributes of the item, as they appeared before the UpdateItem operation. UPDATED_OLD - Returns only the updated attributes, as they appeared before the UpdateItem operation. ALL_NEW - Returns all of the attributes of the item, as they appear after the UpdateItem operation. UPDATED_NEW - Returns only the updated attributes, as they appear after the UpdateItem operation. There is no additional cost associated with requesting a return value aside from the small network and processing overhead of receiving a larger response. No read capacity units are consumed. The values returned are strongly consistent.

Return Value
The response from the UpdateItem service method, as returned by DynamoDB.


ConditionalCheckFailedException A condition specified in the operation could not be evaluated.
InternalServerErrorException An error occurred on the server side.
ItemCollectionSizeLimitExceededException An item collection is too large. This exception is only returned for tables that have one or more local secondary indexes.
ProvisionedThroughputExceededException Your request rate is too high. The AWS SDKs for DynamoDB automatically retry requests that receive this exception. Your request is eventually successful, unless your retry queue is too large to finish. Reduce the frequency of requests and use exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon DynamoDB Developer Guide.
ResourceNotFoundException The operation tried to access a nonexistent table or index. The resource might not be specified correctly, or its status might not be ACTIVE.

Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

Portable Class Library:
Supported in: Windows Store Apps
Supported in: Windows Phone 8.1
Supported in: Xamarin Android
Supported in: Xamarin iOS (Unified)
Supported in: Xamarin.Forms

Supported Versions: 4.6 and above
Supported Platforms: Android, iOS, Standalone

See Also