Out of nowhere, consistant query failures, SQL Azure USA South, Timeout expired. or TransientFailure exceptions..

Getting a bunch of SQL query failures since yesterday morning pacific time. Have not made changes to any code in months, and server load is about same as it has been for a year. Are you guys doing anything to SQL Azure? This is USA South.
This is a 20MB database and I'm doing queries on tables with couple thousand entities, shouldn't fail like this!
Using latest EntityFramework 6.1.1.
Fails at the SQL server no matter where I connect from.
Compiled Linq to Entity queries seem to be failing. The do have some .Includes..
These are the two most common issues:
System.Data.Entity.Core.EntityCommandExecutionException: An error occurred while executing the command definition. See the inner exception for details. ---> System.Data.SqlClient.SqlException: Timeout expired. The timeout period elapsed prior to
completion of the operation or the server is not responding. ---> System.ComponentModel.Win32Exception: The wait operation timed out
   --- End of inner exception stack trace ---
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)
   at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)
   at System.Data.SqlClient.SqlDataReader.TryConsumeMetaData()
   at System.Data.SqlClient.SqlDataReader.get_MetaData()
   at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString)
   at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, SqlDataReader ds)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean asyncWrite)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteDbDataReader(CommandBehavior behavior)
   at System.Data.Common.DbCommand.ExecuteReader(CommandBehavior behavior)
   at System.Data.Entity.Infrastructure.Interception.DbCommandDispatcher.<Reader>b__c(DbCommand t, DbCommandInterceptionContext`1 c)
   at System.Data.Entity.Infrastructure.Interception.InternalDispatcher`1.Dispatch[TTarget,TInterceptionContext,TResult](TTarget target, Func`3 operation, TInterceptionContext interceptionContext, Action`3 executing, Action`3 executed)
   at System.Data.Entity.Infrastructure.Interception.DbCommandDispatcher.Reader(DbCommand command, DbCommandInterceptionContext interceptionContext)
   at System.Data.Entity.Internal.InterceptableDbCommand.ExecuteDbDataReader(CommandBehavior behavior)
   at System.Data.Common.DbCommand.ExecuteReader(CommandBehavior behavior)
   at System.Data.Entity.Core.EntityClient.Internal.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior)
   --- End of inner exception stack trace ---
   at System.Data.Entity.Core.EntityClient.Internal.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior)
   at System.Data.Entity.Core.Objects.Internal.ObjectQueryExecutionPlan.Execute[TResultType](ObjectContext context, ObjectParameterCollection parameterValues)
   at System.Data.Entity.Core.Objects.ObjectQuery`1.<>c__DisplayClass7.<GetResults>b__6()
   at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess)
   at System.Data.Entity.Core.Objects.ObjectQuery`1.<>c__DisplayClass7.<GetResults>b__5()
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
   at System.Data.Entity.Core.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)
   at System.Data.Entity.Core.Objects.ObjectQuery`1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>b__0()
   at System.Data.Entity.Internal.LazyEnumerator`1.MoveNext()
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
and
System.Data.Entity.Core.EntityException: An exception has been raised that is likely due to a transient failure. If you are connecting to a SQL Azure database consider using SqlAzureExecutionStrategy. ---> System.Data.Entity.Core.EntityCommandExecutionException:
An error occurred while executing the command definition. See the inner exception for details. ---> System.Data.SqlClient.SqlException: A transport-level error has occurred when receiving results from the server. (provider: TCP Provider, error: 0 - An existing
connection was forcibly closed by the remote host.) ---> System.ComponentModel.Win32Exception: An existing connection was forcibly closed by the remote host
    --- End of inner exception stack trace ---
    at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
    at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)
    at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj, UInt32 error)
    at System.Data.SqlClient.TdsParserStateObject.ReadSniSyncOverAsync()
    at System.Data.SqlClient.TdsParserStateObject.TryReadNetworkPacket()
    at System.Data.SqlClient.TdsParserStateObject.TryPrepareBuffer()
    at System.Data.SqlClient.TdsParserStateObject.TryReadByte(Byte& value)
    at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)
    at System.Data.SqlClient.SqlDataReader.TryConsumeMetaData()
    at System.Data.SqlClient.SqlDataReader.get_MetaData()
    at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString)
    at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, SqlDataReader ds)
    at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean asyncWrite)
    at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
    at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteDbDataReader(CommandBehavior behavior)
    at System.Data.Entity.Infrastructure.Interception.InternalDispatcher`1.Dispatch[TTarget,TInterceptionContext,TResult](TTarget target, Func`3 operation, TInterceptionContext interceptionContext, Action`3 executing, Action`3 executed)
    at System.Data.Entity.Infrastructure.Interception.DbCommandDispatcher.Reader(DbCommand command, DbCommandInterceptionContext interceptionContext)
    at System.Data.Entity.Core.EntityClient.Internal.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior)
    --- End of inner exception stack trace ---
    at System.Data.Entity.Core.EntityClient.Internal.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior)
    at System.Data.Entity.Core.Objects.Internal.ObjectQueryExecutionPlan.Execute[TResultType](ObjectContext context, ObjectParameterCollection parameterValues)
    at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess)
    at System.Data.Entity.Core.Objects.ObjectQuery`1.<>c__DisplayClass7.<GetResults>b__5()
    at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
    --- End of inner exception stack trace ---
    at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
    at System.Data.Entity.Core.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)
    at System.Data.Entity.Core.Objects.ObjectQuery`1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>b__0()
    at System.Data.Entity.Internal.LazyEnumerator`1.MoveNext()
    at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source)
    at System.Data.Entity.Core.Objects.CompiledQuery.ExecuteQuery[TResult](ObjectContext context, Object[] parameterValues)
    at System.Data.Entity.Core.Objects.CompiledQuery.Invoke[TArg0,TArg1,TResult](TArg0 arg0, TArg1 arg1)

Hi，
I’m writing to follow up with you on this post. Was the problem resolved after performing our action plan steps?If you are satisfied with our solution, I’d like to mark this issue as "Answered". That way, other community members could benefit from
your sharing.
Thanks,
Sofiya Li
Sofiya Li
TechNet Community Support

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SQL Azure: More Intermittent Timeouts

Hi guys,
We have a set of 5 online auction systems running on Windows Azure & SQL Azure. Each system consists of a single web worker and one or more web roles. Each system is using ASP.NET MVC 3 and Entity Framework, Repository Pattern and StructureMap.
The worker role is responsible for housekeeping and runs two groups of processes. One group is run every ten seconds, the other every second. Each process will likely run a database query or stored procedure. These are scheduled with Quartz.net
The web role serves the public interface and back office. Among other basic crud functionality, both of these provide screens which, when open, will repeatedly call controller methods which will result in execution of stored procedure read-only queries.
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The only predictable scenario is during an auction where a specific controller -> sproc starts to timeout during the event (presumably due to load). All other times the errors appear to be completely random and come in singles, two’s, and three’s etc.
even during periods of user inactivity. For example the system will go 18 hours without an error and then could be 5 – 10 errors from different housekeeping methods, or perhaps a user logged on and viewed their account.
Other info:
I have tried to run the affected queries/sprocs on SQL Azure using both local SSMS and Azure web-based query tool – all seem to execute quickly, 1 second max. Query plans not showing anything too suspicious although I am by no means a SQL query performance
expert, or any other kind of expert for that matter
J
We have wrapped all affected areas in Azure SQL Transient Fault Handling Blocks – but as is discussed here
http://social.msdn.microsoft.com/Forums/en-US/ssdsgetstarted/thread/7a50985d-92c2-472f-9464-a6591efec4b3, they do not catch timeouts, and according to “Valery M” this is for good reason.
We are not storing any session information in the database, although asp.net membership information is stored in the database.
We use 1 “SQL Azure server instance” which hosts all 5 databases, two for staging and three for production. All 5 systems are generally active at the same time although it is unlikely that more than one will be in a state of live load use at any given time.
All web roles, worker roles and the SQL Azure server reside in the same Azure Geographical Region.
Any thoughts on where we should be looking? Would it help giving each system it's own SQL Azure server? ... Failing a solution by ourselves - is it possible to get Microsoft to open a support ticket and take a look under the hood at what’s going on in with
our application – how does one go about this?
Thanks in advance.
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Ditto.
New website/database (has only been in production for a week or so). The model we have is pretty simple Azure website MVC EF 6.1.1 using a single database in same region as website. I have monitored for and have never found any throttled connections or deadlocks.
What I have tried so far
I bumped the timeout in the connection string to 60 seconds
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To try to force recreate and see if it was caused by transaction data table locks I ran a query in a transaction block with a WAITFOR delay and then went to the web site and tried to access data that would be locked by that query. That test did generate
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USER C - got 1 (in the same time span)
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Connection Failed SQL State: 'HYT00' SQL Server Error: 0 [Microsoft] [ODBC SQL Server Driver] Login Timeout expired

I backed up my database   on old Notebook    SQLSTRINGCONNECT worked all day for any database in SQL SERVR I created
have brand new computer Notebook
installed SQL SERVER 2008 THE EXACT SAME WAY
I RESTORED THE DATABASE
However, I cannot connect to it via Visual FoxPro 9.0 with   SQLSTRINGCONNECT
or even Windows 7    ODBC Data Source ADministrator

Hi,
We need more information as Olaf asked, but my first guess is that you have permissions problem since the users are not the same users in different machines (local users, or SQL Server users),
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[Personal Site] [Blog] [Facebook]

SQL Azure - query with row_number() executes slow if columns with nvarchar of big size are included

I am linking my question from Stack Overflow here. The link: http://stackoverflow.com/questions/27943913/sql-azure-query-with-row-number-executes-slow-if-columns-with-nvarchar-of-bi
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Hi,
Thanks for posting here.
I suggest you to check this link and optimize your query on sql azure.
http://www.sqlusa.com/articles/query-optimization/
http://sqlblog.com/blogs/paul_white/archive/2011/02/23/Advanced-TSQL-Tuning-Why-Internals-Knowledge-Matters.aspx
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Answer this post
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Hello,
For Web/Business edition database, the maximum limit of concurrent requests is 180. Beyond this limit, you will receive error.
The Max woker threads for Standard(S2) is 100, you should upgrade your database to Permium tier.
The concurrent requests limit of premium database varies depending on the reservation size of a premium database. For example, for P1, the max worker threads is 200.
Reference:Azure SQL Database Resource Governance
Azure SQL Database Service Tiers and Performance Levels
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If you have any feedback on our support, please click here.
Fanny Liu
TechNet Community Support

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http://azure.microsoft.com/en-us/services/sql-database/
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Maybe some usefull posts
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Bhavesh

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Hello,
Just as Latheesh post above, Windows Azure SQL database are not support extended stored procedures. That’s one of the limitations on SQL database, and I don’t know there is another way to achieve the same on Azure.
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Fanny Liu
Fanny Liu
TechNet Community Support

Cannot refresh data in Excel Services with SQL Azure databases

I am using Excel Services on a SharePoint Online.
I get my data from a SQL Azure. When i create my Excel repor with Excel 2013 pro I have no problem. So I upload my file on my Sharepoint and try to refresh data.
Connexion : Power Query - RPT_Event_ByEventType
Erreur : Erreur sur site (OnPremise) : Sorry, the data source for this data connection isn't registered for Power BI. Ask your Power BI
admin to register the data source in the Power BI admin center.
I do not understad why I get that error because my data source is on Azure why It told me "OnPremise" ?

hi,
>> this button of excel gets just address of web and have button for import it
i test it by rest API project , but doesn't work, do you know how it is work?
Do you mean that you don't know how to get the table? You may input the site address into the address box, and then click go button nearby, select the table you want to import into the Excel. Then click import button.That also works for rest API,
and your rest API should get the data that you want
By the way, this is the forum for discussions about Excel develop(VBA ,customization), better to go to TechNet forum for Excel for Excel features question, so that you could get more professional help.
Best Regards
Lan
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Performance is too slow on SQL Azure box

Hi,
Performance is too slow on SQL Azure box (Located in Europe)
Below query returns 500,000 rows in 18 Min. on SQL Azure box (connected via SSMS, located in India)
SELECT * FROM TABLE_1
Whereas, on local server it returns 500,000 rows in (30 sec.)
SQL Azure configuration:
Service Tier/Performance Level : Premium/P1
DTU       : 100
MAX DB Size : 500GB
Max Worker Threads : 200
Max Sessions     : 2400
Benchmark Transaction Rate      : 105 transactions per second
Predictability : Best
Any suggestion would be highly appreciated.
Thanks,

Hello,
Can you please explain in a little more detail the scenario you testing? Are you comparing a SQL Database in Europe against a SQL Database in India? Or a SQL Database with a local, on-premise SQL Server installation?
In case of the first scenario, the roundtrip latency for the connection to the datacenter might play a role.
If you are comparing to a local installation, please note that you might be running against completely different hardware specifications and without network delay, resulting in very different results.
In both cases you can use the below blog post to assess the resource utilization of the SQL Database during the operation:
http://azure.microsoft.com/blog/2014/09/11/azure-sql-database-introduces-new-near-real-time-performance-metrics/
If the DB utilizes up to 100% you might have to consider to upgrade to a higher performance level to achieve the throughput you are looking for.
Thanks,
Jan

Restriction to Left Outer Joins in PS Query

Hello I am trying to do Left Outer JOin in PS QUERY. I need to do dept tbl, job code tbl and locatable as left outer joins with JOB Table. Looks like in PS QUERY there is a error message saying as below. Can someone has any workaround to achieve this in PS QUERY. I know I can create a View and use that in PS QUERY but BUsiness Users are dependent on IT, so that doesn't work. Also, adding JOB table multiple times works but I am looking for better solution if anyone had come accorss working through PS QUERY Outer JOins.
Windows Internet Explorer
Left outer joins must be joined to the last record in the query. (139,290)
OK
Thanks,
SC.

Hi Mike,
According to your description, you want to improve the performance for your DAX query in SQL Server Analysis Service Tabular model, right? Here is a white paper describes strategies and specific techniques for getting the best performance from your tabular
models, including processing and partitioning strategies, DAX query tuning, and server tuning for specific workloads.
http://msdn.microsoft.com/en-us/library/dn393915.aspx
Since this is a complex DAX query, from a support perspective this is really beyond what we can do here in the forums. If you cannot determine your answer here or on your own, consider opening a support case with Microsoft. Visit this link to see the various
support options that are available to better meet your needs:
http://support.microsoft.com/default.aspx?id=fh;en-us;offerprophone
Regards,
Charlie Liao
TechNet Community Support

Out of nowhere, consistant query failures, SQL Azure USA South, Timeout expired. or TransientFailure exceptions..

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