Concurrency handling in Windows Azure

Question

Can somebody help me with getting information regarding "Concurrency handling" in windows azure.? Information like where and al concurrencies will occur in azure? And how to resolve those concurrencies?
It would be grateful if somebody help with it. Thank you.

Answer 1

Since most of the articles I've seen on this reference the Storage Client Library 1.x objects such as TableServiceContext, this is my solution using the newer SDK. See http://msdn.microsoft.com/en-us/library/azure/dn261237.aspx
This block of code should (and does) result in Precondition Failed (Error 412) due to an unmatching eTag.
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(GetConnectionString(account, token));
CloudTableClient tableClient = storageAccount.CreateCloudTableClient();
CloudTable table = tableClient.GetTableReference(container);
table.CreateIfNotExists();
TableOperation retrieveBuildOp = TableOperation.Retrieve<BuildTableEntity>(BuildTablePartitionKey, build);
var specificEntity = (BuildTableEntity)table.Execute(retrieveBuildOp).Result;
var specificEntity2 = (BuildTableEntity)table.Execute(retrieveBuildOp).Result;
specificEntity.ConcurrentDownloads = 33;
TableOperation replaceOp = TableOperation.Replace(specificEntity);
table.Execute(replaceOp);
specificEntity2.ConcurrentDownloads = 22;
TableOperation replaceOp2 = TableOperation.Replace(specificEntity2);
table.Execute(replaceOp2);
/// <summary>
/// Build Table Entity object
/// Includes counter for number of concurrent downloads
/// </summary>
public class BuildTableEntity : TableEntity
/// <summary>
/// Initializes a new instance of the <see cref="BuildTableEntity"/> class.
/// Required parameterless constructor
/// </summary>
public BuildTableEntity()
/// <summary>
/// Initializes a new instance of the <see cref="BuildTableEntity"/> class.
/// </summary>
/// <param name="partitionKey">The partition key of the <see cref="T:Microsoft.WindowsAzure.Storage.Table.TableEntity" /> to be initialized.</param>
/// <param name="rowKey">The row key of the <see cref="T:Microsoft.WindowsAzure.Storage.Table.TableEntity" /> to be initialized.</param>
public BuildTableEntity(string partitionKey, string rowKey)
: base(partitionKey, rowKey)
/// <summary>
/// Gets or sets the number of concurrent downloads.
/// </summary>
public int ConcurrentDownloads { get; set; }