|
public UpdateItem ( |
||
| request | Container for the necessary parameters to execute the UpdateItem service method. | |
| return | ||
private static void ConditionalWriteSample(AmazonDynamoDBClient client)
{
Table table = Table.LoadTable(client, "Actors");
Document d = table.GetItem("Christian Bale");
int version = d["Version"].AsInt();
double height = d["Height"].AsDouble();
Console.WriteLine("Retrieved Item Version #" + version.ToString());
var request = new UpdateItemRequest
{
Key = new Dictionary<string, AttributeValue>() { { "Name", new AttributeValue { S = "Christian Bale" } } },
ExpressionAttributeNames = new Dictionary<string, string>()
{
{"#H", "Height"},
{"#V", "Version"}
},
ExpressionAttributeValues = new Dictionary<string, AttributeValue>()
{
{":ht", new AttributeValue{N=(height+.01).ToString()}},
{":incr", new AttributeValue{N="1"}},
{":v", new AttributeValue{N=version.ToString()}}
},
UpdateExpression = "SET #V = #V + :incr, #H = :ht",
ConditionExpression = "#V = :v",
TableName = "Actors"
};
try
{
Console.ReadKey();
var response = client.UpdateItem(request);
Console.WriteLine("Updated succeeded.");
}
catch (Exception ex)
{
Console.WriteLine("Update failed. " + ex.Message);
}
Console.ReadKey();
}
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
}
}
public virtual void UpdateIfMatch(AmazonDynamoDBClient ddbClient, string tableName, string email, string company,
string firstNameTarget, string firstNameMatch)
{
// Build the request
var updateItemRequest = new UpdateItemRequest
{
TableName = tableName,
Key = new Dictionary<string, AttributeValue>
{
{"Company", new AttributeValue {S = company}},
{"Email", new AttributeValue {S = email}}
},
Expected = new Dictionary<string, ExpectedAttributeValue>
{
{"First", new ExpectedAttributeValue {Value = new AttributeValue {S = firstNameMatch}}}
},
AttributeUpdates = new Dictionary<string, AttributeValueUpdate>
{
{
"First",
new AttributeValueUpdate {Action = "PUT", Value = new AttributeValue {S = firstNameTarget}}
}
}
};
// Submit request
ddbClient.UpdateItem(updateItemRequest);
}
