Amazon.DynamoDBv2.AmazonDynamoDBClient.DeleteItem C# (CSharp) Метод

DeleteItem() публичный Метод

Deletes a single item in a table by primary key. You can perform a conditional delete operation that deletes the item if it exists, or if it has an expected attribute value.

In addition to deleting an item, you can also return the item's attribute values in the same operation, using the ReturnValues parameter.

Unless you specify conditions, the DeleteItem is an idempotent operation; running it multiple times on the same item or attribute does not result in an error response.

Conditional deletes are useful for deleting items only if specific conditions are met. If those conditions are met, DynamoDB performs the delete. Otherwise, the item is not deleted.

/// A condition specified in the operation could not be evaluated. /// /// An error occurred on the server side. /// /// An item collection is too large. This exception is only returned for tables that have /// one or more local secondary indexes. /// /// 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. /// /// The operation tried to access a nonexistent table or index. The resource might not /// be specified correctly, or its status might not be ACTIVE. ///
public DeleteItem ( DeleteItemRequest request ) : DeleteItemResponse
request Amazon.DynamoDBv2.Model.DeleteItemRequest Container for the necessary parameters to execute the DeleteItem service method.
Результат Amazon.DynamoDBv2.Model.DeleteItemResponse
        public DeleteItemResponse DeleteItem(DeleteItemRequest request)
        {
            var marshaller = new DeleteItemRequestMarshaller();
            var unmarshaller = DeleteItemResponseUnmarshaller.Instance;

            return Invoke<DeleteItemRequest,DeleteItemResponse>(request, marshaller, unmarshaller);
        }

Same methods

AmazonDynamoDBClient::DeleteItem ( string tableName, AttributeValue>.Dictionary key ) : DeleteItemResponse
AmazonDynamoDBClient::DeleteItem ( string tableName, AttributeValue>.Dictionary key, ReturnValue returnValues ) : DeleteItemResponse

Usage Example

Пример #1
0
        public void CRUDSamples()
        {
            EnsureTables();

            PutSample();

            {
                #region GetItem Sample

                // Create a client
                AmazonDynamoDBClient client = new AmazonDynamoDBClient();

                // Define item key
                //  Hash-key of the target item is string value "Mark Twain"
                //  Range-key of the target item is string value "The Adventures of Tom Sawyer"
                Dictionary<string, AttributeValue> key = new Dictionary<string, AttributeValue>
                {
                    { "Author", new AttributeValue { S = "Mark Twain" } },
                    { "Title", new AttributeValue { S = "The Adventures of Tom Sawyer" } }
                };

                // Create GetItem request
                GetItemRequest request = new GetItemRequest
                {
                    TableName = "SampleTable",
                    Key = key,
                };

                // Issue request
                var result = client.GetItem(request);

                // View response
                Console.WriteLine("Item:");
                Dictionary<string, AttributeValue> item = result.Item;
                foreach (var keyValuePair in item)
                {
                    Console.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
                        keyValuePair.Key,
                        keyValuePair.Value.S,
                        keyValuePair.Value.N,
                        string.Join(", ", keyValuePair.Value.SS ?? new List<string>()),
                        string.Join(", ", keyValuePair.Value.NS ?? new List<string>()));
                }

                #endregion
            }

            {
                #region UpdateItem Sample

                // Create a client
                AmazonDynamoDBClient client = new AmazonDynamoDBClient();

                // Define item key
                //  Hash-key of the target item is string value "Mark Twain"
                //  Range-key of the target item is string value "The Adventures of Tom Sawyer"
                Dictionary<string, AttributeValue> key = new Dictionary<string, AttributeValue>
                {
                    { "Author", new AttributeValue { S = "Mark Twain" } },
                    { "Title", new AttributeValue { S = "The Adventures of Tom Sawyer" } }
                };

                // Define attribute updates
                Dictionary<string, AttributeValueUpdate> updates = new Dictionary<string, AttributeValueUpdate>();
                // Update item's Setting attribute
                updates["Setting"] = new AttributeValueUpdate()
                {
                    Action = AttributeAction.PUT,
                    Value = new AttributeValue { S = "St. Petersburg, Missouri" }
                };
                // Remove item's Bibliography attribute
                updates["Bibliography"] = new AttributeValueUpdate()
                {
                    Action = AttributeAction.DELETE
                };   
                // Add a new string to the item's Genres SS attribute
                updates["Genres"] = new AttributeValueUpdate()
                {
                    Action = AttributeAction.ADD,
                    Value = new AttributeValue { SS = new List<string> { "Bildungsroman" } }
                };

                // Create UpdateItem request
                UpdateItemRequest request = new UpdateItemRequest
                {
                    TableName = "SampleTable",
                    Key = key,
                    AttributeUpdates = updates
                };

                // Issue request
                client.UpdateItem(request);

                #endregion
            }

            {
                #region DeleteItem Sample

                // Create a client
                AmazonDynamoDBClient client = new AmazonDynamoDBClient();

                // Define item key
                //  Hash-key of the target item is string value "Mark Twain"
                //  Range-key of the target item is string value "The Adventures of Tom Sawyer"
                Dictionary<string, AttributeValue> key = new Dictionary<string, AttributeValue>
                {
                    { "Author", new AttributeValue { S = "Mark Twain" } },
                    { "Title", new AttributeValue { S = "The Adventures of Tom Sawyer" } }
                };

                // Create DeleteItem request
                DeleteItemRequest request = new DeleteItemRequest
                {
                    TableName = "SampleTable",
                    Key = key
                };

                // Issue request
                client.DeleteItem(request);

                #endregion
            }
        }