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• Forcing an External Activation with Service Broker

  - by Davide Mauri

  In these last days I’ve been working quite a lot with Service Broker, a technology I’m really happy to work with, since it can give a lot of satisfaction. The scale-out solution one can easily build is simply astonishing. I’m helping a company to build a very scalable and – yet almost inexpensive – invoicing system that has to be able to scale out using commodity hardware. To offload the work from the main server to satellite “compute nodes” (yes, I’ve borrowed this term from PDW) we’re using Service Broker and the External Activator application available in the SQL Server Feature Pack. For those who are not used to work with SSB, the External Activation is a feature that allows you to intercept the arrival of a message in a queue right from your application code. http://msdn.microsoft.com/en-us/library/ms171617.aspx (Look for “Event-Based Activation”) In order to make life even more easier, Microsoft released the External Activation application that saves you even from writing even this code. http://blogs.msdn.com/b/sql_service_broker/archive/tags/external+activator/ The External Activator application can be configured to execute your own application so that each time a message – an invoice in my case – arrives in the target queue, the invoking application is executed and the invoice is calculated. The very nice feature of External Activator is that it can automatically execute as many configured application in order to process as many messages as your system can handle.  This also a lot of create a scale-out solution, leaving to the developer only a fraction of the problems that usually came with asynchronous programming. Developers are also shielded from Service Broker since everything can be encapsulated in Stored Procedures, so that – for them – developing such scale-out asynchronous solution is not much more complex than just executing a bunch of Stored Procedures. Now, if everything works correctly, you don’t have to bother of anything else. You put messages in the queue and your application, invoked by the External Activator, process them. But what happen if for some reason your application fails to process the messages. For examples, it crashes? The message is safe in the queue so you just need to process it again. But your application is invoked by the External Activator application, so now the question is, how do you wake up that app? Service Broker will engage the activation process only if certain conditions are met: http://msdn.microsoft.com/en-us/library/ms171601.aspx But how we can invoke the activation process manually, without having to wait for another message to arrive (the arrival of a new message is a condition that can fire the activation process)? The “trick” is to do manually with the activation process does: sending a system message to a queue in charge of handling External Activation messages: declare @conversationHandle uniqueidentifier; declare @n xml = N' <EVENT_INSTANCE>   <EventType>QUEUE_ACTIVATION</EventType>   <PostTime>' + CONVERT(CHAR(24),GETDATE(),126) + '</PostTime>   <SPID>' + CAST(@@SPID AS VARCHAR(9)) + '</SPID>   <ServerName>[your_server_name]</ServerName>   <LoginName>[your_login_name]</LoginName>   <UserName>[your_user_name]</UserName>   <DatabaseName>[your_database_name]</DatabaseName>   <SchemaName>[your_queue_schema_name]</SchemaName>   <ObjectName>[your_queue_name]</ObjectName>   <ObjectType>QUEUE</ObjectType> </EVENT_INSTANCE>' begin dialog conversation     @conversationHandle from service        [<your_initiator_service_name>] to service          '<your_event_notification_service>' on contract         [http://schemas.microsoft.com/SQL/Notifications/PostEventNotification] with     encryption = off,     lifetime = 6000 ; send on conversation     @conversationHandle message type     [http://schemas.microsoft.com/SQL/Notifications/EventNotification] (@n) ;     end conversation @conversationHandle; That’s it! Put the code in a Stored Procedure and you can add to your application a button that says “Force Queue Processing” (or something similar) in order to start the activation process whenever you need it (which should not occur too frequently but it may happen). PS I know that the “fire-and-forget” (ending the conversation without waiting for an answer) technique is not a best practice, but in this case I don’t see how it can hurts so I decided to stay very close to the KISS principle []

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• SQL SERVER – Solution to Puzzle – Simulate LEAD() and LAG() without Using SQL Server 2012 Analytic Function

  - by pinaldave

  Earlier I wrote a series on SQL Server Analytic Functions of SQL Server 2012. During the series to keep the learning maximum and having fun, we had few puzzles. One of the puzzle was simulating LEAD() and LAG() without using SQL Server 2012 Analytic Function. Please read the puzzle here first before reading the solution : Write T-SQL Self Join Without Using LEAD and LAG. When I was originally wrote the puzzle I had done small blunder and the question was a bit confusing which I corrected later on but wrote a follow up blog post on over here where I describe the give-away. Quick Recap: Generate following results without using SQL Server 2012 analytic functions. I had received so many valid answers. Some answers were similar to other and some were very innovative. Some answers were very adaptive and some did not work when I changed where condition. After selecting all the valid answer, I put them in table and ran RANDOM function on the same and selected winners. Here are the valid answers. No Joins and No Analytic Functions Excellent Solution by Geri Reshef – Winner of SQL Server Interview Questions and Answers (India | USA) WITH T1 AS (SELECT Row_Number() OVER(ORDER BY SalesOrderDetailID) N, s.SalesOrderID, s.SalesOrderDetailID, s.OrderQty FROM Sales.SalesOrderDetail s WHERE SalesOrderID IN (43670, 43669, 43667, 43663)) SELECT SalesOrderID,SalesOrderDetailID,OrderQty, CASE WHEN N%2=1 THEN MAX(CASE WHEN N%2=0 THEN SalesOrderDetailID END) OVER (Partition BY (N+1)/2) ELSE MAX(CASE WHEN N%2=1 THEN SalesOrderDetailID END) OVER (Partition BY N/2) END LeadVal, CASE WHEN N%2=1 THEN MAX(CASE WHEN N%2=0 THEN SalesOrderDetailID END) OVER (Partition BY N/2) ELSE MAX(CASE WHEN N%2=1 THEN SalesOrderDetailID END) OVER (Partition BY (N+1)/2) END LagVal FROM T1 ORDER BY SalesOrderID, SalesOrderDetailID, OrderQty; GO No Analytic Function and Early Bird Excellent Solution by DHall – Winner of Pluralsight 30 days Subscription -- a query to emulate LEAD() and LAG() ;WITH s AS ( SELECT 1 AS ldOffset, -- equiv to 2nd param of LEAD 1 AS lgOffset, -- equiv to 2nd param of LAG NULL AS ldDefVal, -- equiv to 3rd param of LEAD NULL AS lgDefVal, -- equiv to 3rd param of LAG ROW_NUMBER() OVER (ORDER BY SalesOrderDetailID) AS row, SalesOrderID, SalesOrderDetailID, OrderQty FROM Sales.SalesOrderDetail WHERE SalesOrderID IN (43670, 43669, 43667, 43663) ) SELECT s.SalesOrderID, s.SalesOrderDetailID, s.OrderQty, ISNULL( sLd.SalesOrderDetailID, s.ldDefVal) AS LeadValue, ISNULL( sLg.SalesOrderDetailID, s.lgDefVal) AS LagValue FROM s LEFT OUTER JOIN s AS sLd ON s.row = sLd.row - s.ldOffset LEFT OUTER JOIN s AS sLg ON s.row = sLg.row + s.lgOffset ORDER BY s.SalesOrderID, s.SalesOrderDetailID, s.OrderQty No Analytic Function and Partition By Excellent Solution by DHall – Winner of Pluralsight 30 days Subscription /* a query to emulate LEAD() and LAG() */ ;WITH s AS ( SELECT 1 AS LeadOffset, /* equiv to 2nd param of LEAD */ 1 AS LagOffset, /* equiv to 2nd param of LAG */ NULL AS LeadDefVal, /* equiv to 3rd param of LEAD */ NULL AS LagDefVal, /* equiv to 3rd param of LAG */ /* Try changing the values of the 4 integer values above to see their effect on the results */ /* The values given above of 0, 0, null and null behave the same as the default 2nd and 3rd parameters to LEAD() and LAG() */ ROW_NUMBER() OVER (ORDER BY SalesOrderDetailID) AS row, SalesOrderID, SalesOrderDetailID, OrderQty FROM Sales.SalesOrderDetail WHERE SalesOrderID IN (43670, 43669, 43667, 43663) ) SELECT s.SalesOrderID, s.SalesOrderDetailID, s.OrderQty, ISNULL( sLead.SalesOrderDetailID, s.LeadDefVal) AS LeadValue, ISNULL( sLag.SalesOrderDetailID, s.LagDefVal) AS LagValue FROM s LEFT OUTER JOIN s AS sLead ON s.row = sLead.row - s.LeadOffset /* Try commenting out this next line when LeadOffset != 0 */ AND s.SalesOrderID = sLead.SalesOrderID /* The additional join criteria on SalesOrderID above is equivalent to PARTITION BY SalesOrderID in the OVER clause of the LEAD() function */ LEFT OUTER JOIN s AS sLag ON s.row = sLag.row + s.LagOffset /* Try commenting out this next line when LagOffset != 0 */ AND s.SalesOrderID = sLag.SalesOrderID /* The additional join criteria on SalesOrderID above is equivalent to PARTITION BY SalesOrderID in the OVER clause of the LAG() function */ ORDER BY s.SalesOrderID, s.SalesOrderDetailID, s.OrderQty No Analytic Function and CTE Usage Excellent Solution by Pravin Patel - Winner of SQL Server Interview Questions and Answers (India | USA) --CTE based solution ; WITH cteMain AS ( SELECT SalesOrderID, SalesOrderDetailID, OrderQty, ROW_NUMBER() OVER (ORDER BY SalesOrderDetailID) AS sn FROM Sales.SalesOrderDetail WHERE SalesOrderID IN (43670, 43669, 43667, 43663) ) SELECT m.SalesOrderID, m.SalesOrderDetailID, m.OrderQty, sLead.SalesOrderDetailID AS leadvalue, sLeg.SalesOrderDetailID AS leagvalue FROM cteMain AS m LEFT OUTER JOIN cteMain AS sLead ON sLead.sn = m.sn+1 LEFT OUTER JOIN cteMain AS sLeg ON sLeg.sn = m.sn-1 ORDER BY m.SalesOrderID, m.SalesOrderDetailID, m.OrderQty No Analytic Function and Co-Related Subquery Usage Excellent Solution by Pravin Patel – Winner of SQL Server Interview Questions and Answers (India | USA) -- Co-Related subquery SELECT m.SalesOrderID, m.SalesOrderDetailID, m.OrderQty, ( SELECT MIN(SalesOrderDetailID) FROM Sales.SalesOrderDetail AS l WHERE l.SalesOrderID IN (43670, 43669, 43667, 43663) AND l.SalesOrderID >= m.SalesOrderID AND l.SalesOrderDetailID > m.SalesOrderDetailID ) AS lead, ( SELECT MAX(SalesOrderDetailID) FROM Sales.SalesOrderDetail AS l WHERE l.SalesOrderID IN (43670, 43669, 43667, 43663) AND l.SalesOrderID <= m.SalesOrderID AND l.SalesOrderDetailID < m.SalesOrderDetailID ) AS leag FROM Sales.SalesOrderDetail AS m WHERE m.SalesOrderID IN (43670, 43669, 43667, 43663) ORDER BY m.SalesOrderID, m.SalesOrderDetailID, m.OrderQty This was one of the most interesting Puzzle on this blog. Giveaway Winners will get following giveaways. Geri Reshef and Pravin Patel SQL Server Interview Questions and Answers (India | USA) DHall Pluralsight 30 days Subscription Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, Readers Contribution, Readers Question, SQL, SQL Authority, SQL Function, SQL Puzzle, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• SQL SERVER – Simple Example of Snapshot Isolation – Reduce the Blocking Transactions

  - by pinaldave

  To learn any technology and move to a more advanced level, it is very important to understand the fundamentals of the subject first. Today, we will be talking about something which has been quite introduced a long time ago but not properly explored when it comes to the isolation level. Snapshot Isolation was introduced in SQL Server in 2005. However, the reality is that there are still many software shops which are using the SQL Server 2000, and therefore cannot be able to maintain the Snapshot Isolation. Many software shops have upgraded to the later version of the SQL Server, but their respective developers have not spend enough time to upgrade themselves with the latest technology. “It works!” is a very common answer of many when they are asked about utilizing the new technology, instead of backward compatibility commands. In one of the recent consultation project, I had same experience when developers have “heard about it” but have no idea about snapshot isolation. They were thinking it is the same as Snapshot Replication – which is plain wrong. This is the same demo I am including here which I have created for them. In Snapshot Isolation, the updated row versions for each transaction are maintained in TempDB. Once a transaction has begun, it ignores all the newer rows inserted or updated in the table. Let us examine this example which shows the simple demonstration. This transaction works on optimistic concurrency model. Since reading a certain transaction does not block writing transaction, it also does not block the reading transaction, which reduced the blocking. First, enable database to work with Snapshot Isolation. Additionally, check the existing values in the table from HumanResources.Shift. ALTER DATABASE AdventureWorks SET ALLOW_SNAPSHOT_ISOLATION ON GO SELECT ModifiedDate FROM HumanResources.Shift GO Now, we will need two different sessions to prove this example. First Session: Set Transaction level isolation to snapshot and begin the transaction. Update the column “ModifiedDate” to today’s date. -- Session 1 SET TRANSACTION ISOLATION LEVEL SNAPSHOT BEGIN TRAN UPDATE HumanResources.Shift SET ModifiedDate = GETDATE() GO Please note that we have not yet been committed to the transaction. Now, open the second session and run the following “SELECT” statement. Then, check the values of the table. Please pay attention on setting the Isolation level for the second one as “Snapshot” at the same time when we already start the transaction using BEGIN TRAN. -- Session 2 SET TRANSACTION ISOLATION LEVEL SNAPSHOT BEGIN TRAN SELECT ModifiedDate FROM HumanResources.Shift GO You will notice that the values in the table are still original values. They have not been modified yet. Once again, go back to session 1 and begin the transaction. -- Session 1 COMMIT After that, go back to Session 2 and see the values of the table. -- Session 2 SELECT ModifiedDate FROM HumanResources.Shift GO You will notice that the values are yet not changed and they are still the same old values which were there right in the beginning of the session. Now, let us commit the transaction in the session 2. Once committed, run the same SELECT statement once more and see what the result is. -- Session 2 COMMIT SELECT ModifiedDate FROM HumanResources.Shift GO You will notice that it now reflects the new updated value. I hope that this example is clear enough as it would give you good idea how the Snapshot Isolation level works. There is much more to write about an extra level, READ_COMMITTED_SNAPSHOT, which we will be discussing in another post soon. If you wish to use this transaction’s Isolation level in your production database, I would appreciate your comments about their performance on your servers. I have included here the complete script used in this example for your quick reference. ALTER DATABASE AdventureWorks SET ALLOW_SNAPSHOT_ISOLATION ON GO SELECT ModifiedDate FROM HumanResources.Shift GO -- Session 1 SET TRANSACTION ISOLATION LEVEL SNAPSHOT BEGIN TRAN UPDATE HumanResources.Shift SET ModifiedDate = GETDATE() GO -- Session 2 SET TRANSACTION ISOLATION LEVEL SNAPSHOT BEGIN TRAN SELECT ModifiedDate FROM HumanResources.Shift GO -- Session 1 COMMIT -- Session 2 SELECT ModifiedDate FROM HumanResources.Shift GO -- Session 2 COMMIT SELECT ModifiedDate FROM HumanResources.Shift GO Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Transaction Isolation

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• SQL SERVER – Service Broker and CAP_CPU_PERCENT – Limiting SQL Server Instances to CPU Usage

  - by pinaldave

  I have mentioned several times on this blog that the best part of blogging is the questions I receive from readers. They are often very interesting. The questions from readers give me a good idea what other readers might be thinking as well. After reading my earlier article Simple Example to Configure Resource Governor – Introduction to Resource Governor – I received an email from a reader and we exchanged a few emails. After exchanging emails we both figured out what is going on. It was indeed interesting and reader suggested to that I should blog about it.  I asked for permission to publish his name but he does not like the attention so we will just call him Jeff. I have converted our emails into chat for easy consumption. Jeff: Your script does not work at all. I think either there is a bug in SQL Server. Pinal: Would you please explain in detail? Jeff: Your code does not limit the CPU usage? Pinal: How did you measure it? Jeff: Well, we have third party tools for it but let us say I have limited the resources for Reporting Services and used your script described in your blog. After that I ran only reporting service workload the CPU is still used more than 100% and it is not limited to 30% as described in your script. Clearly something is wrong somewhere. Pinal: Did you say you ONLY ran reporting server load? Jeff: Yeah, to validate I ran ONLY reporting server load and CPU did not throttle at 30% as per your script. Pinal: Oh! I get it here is the answer - CAP_CPU_PERCENT = 30. Use it. Jeff: What is that, I think your earlier script says it will throttle the Reporting Service workload and Application/OLTP workload and balance it. Pinal: Exactly, that is correct. Jeff: You need to write more in email buddy! Just like your blogs, your answers do not make sense! No Offense! Pinal: Hmm…feedback well taken. Let me try again. In SQL Server 2012 there are a few enhancements with regards to SQL Server Resource Governor. One of the enhancement is how the resources are allocated. Let me explain you with examples. Configuration: [Read Earlier Post] Reporting Workload: MIN_CPU_PERCENT=0, MAX_CPU_PERCENT=30 Application/OLTP Workload: MIN_CPU_PERCENT=50, MAX_CPU_PERCENT=100 Example 1: If there is only Reporting Workload on the server: SQL Server will not limit usage of CPU to only 30% workload but SQL Server instance will use all available CPU (if needed). In another word in this scenario it will use more than 30% CPU. Example 2: If there is Reproting Workload and heavy Application/OLTP workload: SQL Server will allocate a maximum of 30% CPU resources to Reporting Workload and allocate remaining resources to heavy application/OLTP workload. The reason for this enhancement is for better utilization of the resources. Let us think, if there is only single workload, which we have limited to max CPU usage to 30%. The other unused available CPU resources is now wasted. In this situation SQL Server allows the workload to use more than 30% resources leading to overall improved/optimized performance. However, in the case of multiple workload where lots of resources are needed the limits specified in MAX_CPU_PERCENT are acknowledged. Example 3: If there is a situation where the max CPU workload has to be enforced: This is a very interesting scenario, in the case when the max CPU workload has to be enforced irrespective of the workload and enhanced algorithm, the keyword CAP_CPU_PERCENT is essential. It specifies a hard cap on the CPU bandwidth that all requests in the resource pool will receive. It will never let CPU usage for reporting workload to go over 30% in our case. You can use the key word as follows: -- Creating Resource Pool for Report Server CREATE RESOURCE POOL ReportServerPool WITH ( MIN_CPU_PERCENT=0, MAX_CPU_PERCENT=30, CAP_CPU_PERCENT=40, MIN_MEMORY_PERCENT=0, MAX_MEMORY_PERCENT=30) GO Notice that there is MAX_CPU_PERCENT=30 and CAP_CPU_PERCENT=40, what it means is that when SQL Server Instance is under heavy load under different workload it will use the maximum CPU at 30%. However, when the SQL Server instance is not under workload it will go over the 30% limit. However, as CAP_CPU_PERCENT is set to 40, it will not go over 40% in any case by limiting the usage of CPU. CAP_CPU_PERCENT puts a hard limit on the resources usage by workload. Jeff: Nice Pinal, you should blog about it. [A day passes by] Pinal: Jeff, it is done! Click here to read it. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Service Broker

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• SQL SERVER – Advanced Data Quality Services with Melissa Data – Azure Data Market

  - by pinaldave

  There has been much fanfare over the new SQL Server 2012, and especially around its new companion product Data Quality Services (DQS). Among the many new features is the addition of this integrated knowledge-driven product that enables data stewards everywhere to profile, match, and cleanse data. In addition to the homegrown rules that data stewards can design and implement, there are also connectors to third party providers that are hosted in the Azure Datamarket marketplace.  In this review, I leverage SQL Server 2012 Data Quality Services, and proceed to subscribe to a third party data cleansing product through the Datamarket to showcase this unique capability. Crucial Questions For the purposes of the review, I used a database I had in an Excel spreadsheet with name and address information. Upon a cursory inspection, there are miscellaneous problems with these records; some addresses are missing ZIP codes, others missing a city, and some records are slightly misspelled or have unparsed suites. With DQS, I can easily add a knowledge base to help standardize my values, such as for state abbreviations. But how do I know that my address is correct? And if my address is not correct, what should it be corrected to? The answer lies in a third party knowledge base by the acknowledged USPS certified address accuracy experts at Melissa Data. Reference Data Services Within DQS there is a handy feature to actually add reference data from many different third-party Reference Data Services (RDS) vendors. DQS simplifies the processes of cleansing, standardizing, and enriching data through custom rules and through service providers from the Azure Datamarket. A quick jump over to the Datamarket site shows me that there are a handful of providers that offer data directly through Data Quality Services. Upon subscribing to these services, one can attach a DQS domain or composite domain (fields in a record) to a reference data service provider, and begin using it to cleanse, standardize, and enrich that data. Besides what I am looking for (address correction and enrichment), it is possible to subscribe to a host of other services including geocoding, IP address reference, phone checking and enrichment, as well as name parsing, standardization, and genderization.  These capabilities extend the data quality that DQS has natively by quite a bit. For my current address correction review, I needed to first sign up to a reference data provider on the Azure Data Market site. For this example, I used Melissa Data’s Address Check Service. They offer free one-month trials, so if you wish to follow along, or need to add address quality to your own data, I encourage you to sign up with them. Once I subscribed to the desired Reference Data Provider, I navigated my browser to the Account Keys within My Account to view the generated account key, which I then inserted into the DQS Client – Configuration under the Administration area. Step by Step to Guide That was all it took to hook in the subscribed provider -Melissa Data- directly to my DQS Client. The next step was for me to attach and map in my Reference Data from the newly acquired reference data provider, to a domain in my knowledge base. On the DQS Client home screen, I selected “New Knowledge Base” under Knowledge Base Management on the left-hand side of the home screen. Under New Knowledge Base, I typed a Name and description of my new knowledge base, then proceeded to the Domain Management screen. Here I established a series of domains (fields) and then linked them all together as a composite domain (record set). Using the Create Domain button, I created the following domains according to the fields in my incoming data: Name Address Suite City State Zip I added a Suite column in my domain because Melissa Data has the ability to return missing Suites based on last name or company. And that’s a great benefit of using these third party providers, as they have data that the data steward would not normally have access to. The bottom line is, with these third party data providers, I can actually improve my data. Next, I created a composite domain (fulladdress) and added the (field) domains into the composite domain. This essentially groups our address fields together in a record to facilitate the full address cleansing they perform. I then selected my newly created composite domain and under the Reference Data tab, added my third party reference data provider –Melissa Data’s Address Check- and mapped in each domain that I had to the provider’s Schema. Now that my composite domain has been married to the Reference Data service, I can take the newly published knowledge base and create a project to cleanse and enrich my data. My next task was to create a new Data Quality project, mapping in my data source and matching it to the appropriate domain column, and then kick off the verification process. It took just a few minutes with some progress indicators indicating that it was working. When the process concluded, there was a helpful set of tabs that place the response records into categories: suggested; new; invalid; corrected (automatically); and correct. Accepting the suggestions provided by  Melissa Data allowed me to clean up all the records and flag the invalid ones. It is very apparent that DQS makes address data quality simplistic for any IT professional. Final Note As I have shown, DQS makes data quality very easy. Within minutes I was able to set up a data cleansing and enrichment routine within my data quality project, and ensure that my address data was clean, verified, and standardized against real reference data. As reviewed here, it’s easy to see how both SQL Server 2012 and DQS work to take what used to require a highly skilled developer, and empower an average business or database person to consume external services and clean data. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Utility, T SQL, Technology Tagged: DQS

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• SQL SERVER – SSMS: Memory Usage By Memory Optimized Objects Report

  - by Pinal Dave

  At conferences and at speaking engagements at the local UG, there is one question that keeps on coming which I wish were never asked. The question around, “Why is SQL Server using up all the memory and not releasing even when idle?” Well, the answer can be long and with the release of SQL Server 2014, this got even more complicated. This release of SQL Server 2014 has the option of introducing In-Memory OLTP which is completely new concept and our dependency on memory has increased multifold. In reality, nothing much changes but we have memory optimized objects (Tables and Stored Procedures) additional which are residing completely in memory and improving performance. As a DBA, it is humanly impossible to get a hang of all the innovations and the new features introduced in the next version. So today’s blog is around the report added to SSMS which gives a high level view of this new feature addition. This reports is available only from SQL Server 2014 onwards because the feature was introduced in SQL Server 2014. Earlier versions of SQL Server Management Studio would not show the report in the list. If we try to launch the report on the database which is not having In-Memory File group defined, then we would see the message in report. To demonstrate, I have created new fresh database called MemoryOptimizedDB with no special file group. Here is the query used to identify whether a database has memory-optimized file group or not. SELECT TOP(1) 1 FROM sys.filegroups FG WHERE FG.[type] = 'FX' Once we add filegroup using below command, we would see different version of report. USE [master] GO ALTER DATABASE [MemoryOptimizedDB] ADD FILEGROUP [IMO_FG] CONTAINS MEMORY_OPTIMIZED_DATA GO The report is still empty because we have not defined any Memory Optimized table in the database.  Total allocated size is shown as 0 MB. Now, let’s add the folder location into the filegroup and also created few in-memory tables. We have used the nomenclature of IMO to denote “InMemory Optimized” objects. USE [master] GO ALTER DATABASE [MemoryOptimizedDB] ADD FILE ( NAME = N'MemoryOptimizedDB_IMO', FILENAME = N'E:\Program Files\Microsoft SQL Server\MSSQL12.SQL2014\MSSQL\DATA\MemoryOptimizedDB_IMO') TO FILEGROUP [IMO_FG] GO You may have to change the path based on your SQL Server configuration. Below is the script to create the table. USE MemoryOptimizedDB GO --Drop table if it already exists. IF OBJECT_ID('dbo.SQLAuthority','U') IS NOT NULL DROP TABLE dbo.SQLAuthority GO CREATE TABLE dbo.SQLAuthority ( ID INT IDENTITY NOT NULL, Name CHAR(500)  COLLATE Latin1_General_100_BIN2 NOT NULL DEFAULT 'Pinal', CONSTRAINT PK_SQLAuthority_ID PRIMARY KEY NONCLUSTERED (ID), INDEX hash_index_sample_memoryoptimizedtable_c2 HASH (Name) WITH (BUCKET_COUNT = 131072) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA) GO As soon as above script is executed, table and index both are created. If we run the report again, we would see something like below. Notice that table memory is zero but index is using memory. This is due to the fact that hash index needs memory to manage the buckets created. So even if table is empty, index would consume memory. More about the internals of how In-Memory indexes and tables work will be reserved for future posts. Now, use below script to populate the table with 10000 rows INSERT INTO SQLAuthority VALUES (DEFAULT) GO 10000 Here is the same report after inserting 1000 rows into our InMemory table.    There are total three sections in the whole report. Total Memory consumed by In-Memory Objects Pie chart showing memory distribution based on type of consumer – table, index and system. Details of memory usage by each table. The information about all three is taken from one single DMV, sys.dm_db_xtp_table_memory_stats This DMV contains memory usage statistics for both user and system In-Memory tables. If we query the DMV and look at data, we can easily notice that the system tables have negative object IDs.  So, to look at user table memory usage, below is the over-simplified version of query. USE MemoryOptimizedDB GO SELECT OBJECT_NAME(OBJECT_ID), * FROM sys.dm_db_xtp_table_memory_stats WHERE OBJECT_ID > 0 GO This report would help DBA to identify which in-memory object taking lot of memory which can be used as a pointer for designing solution. I am sure in future we will discuss at lengths the whole concept of In-Memory tables in detail over this blog. To read more about In-Memory OLTP, have a look at In-Memory OLTP Series at Balmukund’s Blog. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL Tagged: SQL Memory, SQL Reports

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• Comments on Comments

  - by Joe Mayo

  I almost tweeted a reply to Capar Kleijne's question about comments on Twitter, but realized that my opinion exceeded 140 characters. The following is based upon my experience with extremes and approaches that I find useful in code comments. There are a couple extremes that I've seen and reasons why people go the distance in each approach. The most common extreme is no comments in the code at all.  A few bad reasons why this happens is because a developer is in a hurry, sloppy, or is interested in job preservation. The unfortunate result is that the code is difficult to understand and hard to maintain. The drawbacks to no comments in code are a primary reason why teachers drill the need for commenting code into our heads.  This viewpoint assumes the lack of comments are bad because the code is bad, but there is another reason for not commenting that is gaining more popularity. I've heard/and read that code should be self documenting. Following this thought pattern, if code is well written with meaningful names, there should not be a reason for comments.  An addendum to this argument is that comments are often neglected and get out-of-date, but the code is what is kept up-to-date. Presumably, if code contained very good naming, it would be easy to maintain.  This is a noble perspective and I like the practice of meaningful naming of identifiers. However, I think it's also an extreme approach that doesn't cover important cases.  i.e. If an identifier is named badly (subjective differences in opinion) or not changed appropriately during maintenance, then the badly named identifier is no more useful than a stale comment. These were the two no-comment extremes, so let's look at the too many comments extreme. On a regular basis, I'll see cases where the code is over-commented; not nearly as often as the no-comment scenarios, but still prevalent.  These are examples of where every single line in the code is commented.  These comments make the code harder to read because they get in the way of the algorithm.  In most cases, the comments parrot what each line of code does.  If a developer understands the language, then most statements are immediately intuitive.  i.e. what use is it to say that I'm assigning foo to bar when it's clear what the code is doing. I think that over-commenting code is a waste of time that slows down initial development and maintenance.  Understandably, the developer's intentions are admirable because they've had it beaten into their heads that they must comment. However, I think it's an extreme and prefer a more moderate approach. I don't think the extremes do justice to code because each can make maintenance harder.  No comments on bad code is obviously a problem, but the other two extremes are subtle and require qualification to address properly. The problem I see with the code-as-documentation approach is that it doesn't lift the developer out of the algorithm to identify dependencies, intentions, and hacks. Any developer can read code and follow an algorithm, but they still need to know where it fits into the big picture of the application. Because of indirections with language features like interfaces, delegates, and virtual members, code can become complex.  Occasionally, it's useful to point out a nuance or reason why a piece of code is there. i.e. If you've building an app that communicates via HTTP, you'll have certain headers to include for the endpoint, and it could be useful to point out why the code for setting those header values is there and how they affect the application. An argument against this could be that you should extract that code into a separate method with a meaningful name to describe the scenario.  My problem with such an approach would be that your code base becomes even more difficult to navigate and work with because you have all of this extra code just to make the code more meaningful. My opinion is that a simple and well-stated comment stating the reasons and intention for the code is more natural and convenient to the initial developer and maintainer.  I just don't agree with the approach of going out of the way to avoid making a comment.  I'm also concerned that some developers would take this approach as an excuse to not comment their bad code. Another area where I like comments is on documentation comments.  Java has it and so does C# and VB.  It's convenient because we can build automated tools that extract these comments.  These extracted comments are often much better than no documentation at all.  The "go read the code" answer always doesn't fulfill the need for a quick summary of an API. To summarize, I think that the extremes of no comments and too many comments are less than desirable approaches. I prefer documentation comments to explain each class and member (API level) and code comments as necessary to supplement well-written code. Joe

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• Seven Worlds will collide…. High Availability BI is not such a Distant Sun.

  - by Testas

  Over the last 5 years I have observed Microsoft persevere with the notion of Self Service BI over a series of conferences as far back as SQLBits V in Newport. The release of SQL Server 2012, improvements in Excel and the integration with SharePoint 2010 is making this a reality. Business users are now empowered to create their own BI reports through a number of different technologies such as PowerPivot, PowerView and Report Builder. This opens up a whole new way of working; improving staff productivity, promoting efficient decision making and delivering timely business reports. There is, however; a serious question to answer. What happens should any of these applications become unavailable? More to the point, how would the business react should key business users be unable to fulfil reporting requests for key management meetings when they require it?  While the introduction of self-service BI will provide instant access to the creation of management information reports, it will also cause instant support calls should the access to the data become unavailable. These are questions that are often overlooked when a business evaluates the need for self-service BI. But as I have written in other blog posts, the thirst for information is unquenchable once the business users have access to the data. When they are unable to access the information, you will be the first to know about it and will be expected to have a resolution to the downtime as soon as possible. The world of self-service BI is pushing reporting and analytical databases to the tier 1 application level for some of Coeo’s customers. A level that is traditionally associated with mission critical OLTP environments. There is recognition that by making BI readily available to the business user, provisions also need to be made to ensure that the solution is highly available so that there is minimal disruption to the business. This is where High Availability BI infrastructures provide a solution. As there is a convergence of technologies to support a self-service BI culture, there is also a convergence of technologies that need to be understood in order to provide the high availability architecture required to support the self-service BI infrastructure. While you may not be the individual that implements these components, understanding the concepts behind these components will empower you to have meaningful discussions with the right people should you put this infrastructure in place. There are 7 worlds that you will have to understand to successfully implement a highly available BI infrastructure   1.       Server/Virtualised server hardware/software 2.       DNS 3.       Network Load Balancing 4.       Active Directory 5.       Kerberos 6.       SharePoint 7.       SQL Server I have found myself over the last 6 months reaching out to knowledge that I learnt years ago when I studied for the Windows 2000 and 2003 (MCSE) Microsoft Certified System Engineer. (To the point that I am resuming my studies for the Windows Server 2008 equivalent to be up to date with newer technologies) This knowledge has proved very useful in the numerous engagements I have undertaken since being at Coeo, particularly when dealing with High Availability Infrastructures. As a result of running my session at SQLBits X and SQL Saturday in Dublin, the feedback I have received has been that many individuals desire to understand more of the concepts behind the first 6 “worlds” in the list above. Over the coming weeks, a series of blog posts will be put on this site to help understand the key concepts of each area as it pertains to a High Availability BI Infrastructure. Each post will not provide exhaustive coverage of the topic. For example DNS can be a book in its own right when you consider that there are so many different configuration options with Forward Lookup, Reverse Lookups, AD Integrated Zones and DNA forwarders to name some examples. What I want to do is share the pertinent points as it pertains to the BI infrastructure that you build so that you are equipped with the knowledge to have the right discussion when planning this infrastructure. Next, we will focus on the server infrastructure that will be required to support the High Availability BI Infrastructure, from both a physical box and virtualised perspective. Thanks   Chris

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• Using the “Settings.settings” functionalities in VB.NET can be tricky…

  - by Vincent Grondin

  Sometime you’re searching for something forever and when you find it, you realize it was right under your nose.  Maybe you were distracted by other things around… or maybe that thing right under your nose was so well hidden that it deserves a blog post…   That happened to me a few days ago while using the “Settings.settings” functionalities in my VB.NET application…  I thought it was a cool feature and I decided to use it…  So there I am adding new settings with “USER” scope and StringCollection as the data type, testing my application and everything works perfectly fine...  That was before I decided to modify the “Value” of one of my settings…  After changing the value of one of my settings, I start my application again and, to my surprise, my new values aren’t showing!  Hmmm… That’s odd…  My setting was a pretty long list of strings so I was rather angry at myself for not saving my work after I was done…  So I open up the Settings.setting in the designer and click the ellipsis symbol to enter my string collection again, but to my great pleasure (and disbelief) my strings are there!!!  Alright, you rock VB.NET!  You’ve just save me a bunch of typing time and I’m thinking it’s just a simple Visual Studio glitch…  I hit “Save” then “Save All” (just in case) and finally I rebuild everything and fire up my app once again.  Huh?  Where are my darn strings????????  Ok there’s a bug there…  I open up the app.config and my new strings are there!!!  Alright, let’s recap…  My new strings are in the app.config, they show correctly in the Settings.settings designer UI but they aren’t showing at runtime…  Hmmmm?  Let’s try something else…  Let’s start the application but outside Visual Studio this time… I fire up the exe and BAM!  My strings where there!  I “alt-tab” and hit “F5” and BOOM, no strings!  So it’s a bug in the Visual Studio environment… or could it be a FEATURE?  I must admit that I’m a little confused over what’s a bug and what’s a feature in Visual Studio… lol!   Finally I found out there’s a “cache” for your Visual Studio located here:  C:\Users\<your username>\AppData\Local\Microsoft\<your app name and a very weird temp ID>\<your app version>\user.config When using the “Settings.settings” with a setting of scope “user”, this file is out of sync with your app.config until you manually decide to update it… The button is right there… under your nose… at the top left corner of your screen in the settings designer…  See the big “Synchronize” button there?  Yep…  Now that’s user friendly isn’t it?  Oh, and wait until you see what it does when you click it…  It prompts you and basically says:  “Would you like your settings to start working inside Visual Studio now that you found out that I exist?” and of course the right answer is yes… or rather “OK”…  Unfortunately, you have to do this every time you edit a value… On the other hand, adding and removing settings seem to work flawlessly without having to click this magical button… go figure!  Oh and I almost forgot… this great “feature” is only available for VB.NET…  A project in C# using Settings.settings will work perfectly EVEN when editing values… Here’s a screenshot that shows this important button: Button Using other data types appears to work perfectly well…   Maybe it’s simply related to the StringCollection data type?  If you are a VB.NET programmer, you should pay attention to this when you plan on using the settings functionalities and your scope is “user” and your data type is StringCollection… Happy coding all!

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• New .NET Library for Accessing the Survey Monkey API

  - by Ben Emmett

  I’ve used Survey Monkey’s API for a while, and though it’s pretty powerful, there’s a lot of boilerplate each time it’s used in a new project, and the json it returns needs a bunch of processing to be able to use the raw information. So I’ve finally got around to releasing a .NET library you can use to consume the API more easily. The main advantages are: Only ever deal with strongly-typed .NET objects, making everything much more robust and a lot faster to get going Automatically handles things like rate-limiting and paging through results Uses combinations of endpoints to get all relevant data for you, and processes raw response data to map responses to questions To start, either install it using NuGet with PM> Install-Package SurveyMonkeyApi (easier option), or grab the source from https://github.com/bcemmett/SurveyMonkeyApi if you prefer to build it yourself. You’ll also need to have signed up for a developer account with Survey Monkey, and have both your API key and an OAuth token. A simple usage would be something like: string apiKey = "KEY"; string token = "TOKEN"; var sm = new SurveyMonkeyApi(apiKey, token); List<Survey> surveys = sm.GetSurveyList(); The surveys object is now a list of surveys with all the information available from the /surveys/get_survey_list API endpoint, including the title, id, date it was created and last modified, language, number of questions / responses, and relevant urls. If there are more than 1000 surveys in your account, the library pages through the results for you, making multiple requests to get a complete list of surveys. All the filtering available in the API can be controlled using .NET objects. For example you might only want surveys created in the last year and containing “pineapple” in the title: var settings = new GetSurveyListSettings { Title = "pineapple", StartDate = DateTime.Now.AddYears(-1) }; List<Survey> surveys = sm.GetSurveyList(settings); By default, whenever optional fields can be requested with a response, they will all be fetched for you. You can change this behaviour if for some reason you explicitly don’t want the information, using var settings = new GetSurveyListSettings { OptionalData = new GetSurveyListSettingsOptionalData { DateCreated = false, AnalysisUrl = false } }; Survey Monkey’s 7 read-only endpoints are supported, and the other 4 which make modifications to data might be supported in the future. The endpoints are: Endpoint Method Object returned /surveys/get_survey_list GetSurveyList() List<Survey> /surveys/get_survey_details GetSurveyDetails() Survey /surveys/get_collector_list GetCollectorList() List<Collector> /surveys/get_respondent_list GetRespondentList() List<Respondent> /surveys/get_responses GetResponses() List<Response> /surveys/get_response_counts GetResponseCounts() Collector /user/get_user_details GetUserDetails() UserDetails /batch/create_flow Not supported Not supported /batch/send_flow Not supported Not supported /templates/get_template_list Not supported Not supported /collectors/create_collector Not supported Not supported The hierarchy of objects the library can return is Survey List<Page> List<Question> QuestionType List<Answer> List<Item> List<Collector> List<Response> Respondent List<ResponseQuestion> List<ResponseAnswer> Each of these classes has properties which map directly to the names of properties returned by the API itself (though using PascalCasing which is more natural for .NET, rather than the snake_casing used by SurveyMonkey). For most users, Survey Monkey imposes a rate limit of 2 requests per second, so by default the library leaves at least 500ms between requests. You can request higher limits from them, so if you want to change the delay between requests just use a different constructor: var sm = new SurveyMonkeyApi(apiKey, token, 200); //200ms delay = 5 reqs per sec There’s a separate cap of 1000 requests per day for each API key, which the library doesn’t currently enforce, so if you think you’ll be in danger of exceeding that you’ll need to handle it yourself for now.  To help, you can see how many requests the current instance of the SurveyMonkeyApi object has made by reading its RequestsMade property. If the library encounters any errors, including communicating with the API, it will throw a SurveyMonkeyException, so be sure to handle that sensibly any time you use it to make calls. Finally, if you have a survey (or list of surveys) obtained using GetSurveyList(), the library can automatically fill in all available information using sm.FillMissingSurveyInformation(surveys); For each survey in the list, it uses the other endpoints to fill in the missing information about the survey’s question structure, respondents, and responses. This results in at least 5 API calls being made per survey, so be careful before passing it a large list. It also joins up the raw response information to the survey’s question structure, so that for each question in a respondent’s set of replies, you can access a ProcessedAnswer object. For example, a response to a dropdown question (from the /surveys/get_responses endpoint) might be represented in json as { "answers": [ { "row": "9384627365", } ], "question_id": "615487516" } Separately, the question’s structure (from the /surveys/get_survey_details endpoint) might have several possible answers, one of which might look like { "text": "Fourth item in dropdown list", "visible": true, "position": 4, "type": "row", "answer_id": "9384627365" } The library understands how this mapping works, and uses that to give you the following ProcessedAnswer object, which first describes the family and type of question, and secondly gives you the respondent’s answers as they relate to the question. Survey Monkey has many different question types, with 11 distinct data structures, each of which are supported by the library. If you have suggestions or spot any bugs, let me know in the comments, or even better submit a pull request .

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• SQL Server service accounts and SPNs

  - by simonsabin

  Service Principal Names (SPNs) are a must for kerberos authentication which is a must when using sharepoint, reporting services and sql server where you access one server that then needs to access another resource, this is called the double hop. The reason this is a complex problem is that the second hop has to be done with impersonation/delegation. For this to work there needs to be a way for the security system to make sure that the service in the middle is allowed to impersonate you, after all you are not giving the service your password. To do this you need to be using kerberos. The following is my simple interpretation of how kerberos works. I find the Kerberos documentation rediculously complex so the following might be sligthly wrong but I think its close enough. Keberos works on a ticketing system, the prinicipal is that you get a security token from AD and then you can pass that to the service in the middle which can then use that token to impersonate you. For that to work AD has to be able to identify who is allowed to use the token, in this case the service account.But how do you as a client know what service account the service in the middle is configured with. The answer is SPNs. The SPN is the mapping between your logical connection to the service account. One type of SPN is for the DNS name for the server and the port. i.e. MySQL.mydomain.com and 1433. You can see how this maps to SQL Server on that server, but how does it map to the account. Well it can be done in two ways, either you can have a mapping defined in AD or AD can use a default mapping (this is something I didn't know about). To map the SPN in AD then you have to add the SPN to the user account, this is documented in the first link below either directly or using a tool called SetSPN. You might say that is complex, well it is and thats why SQL Server tries to do it for you, at start up it tries to connect to AD and set the SPN on the account it is running as, clearly that can only happen IF SQL is running as a domain account AND importantly it has permission to do so. By default a normal domain user account doesn't have the correct permission, and is why so many people have this problem. If the account is a domain admin then it will have permission, but non of us run SQL using domain admin accounts do we. You might also note that the SPN contains the port number (this isn't a requirement now in sql 2008 but I won't go into that), so if you set it manually and you are using dynamic ports (the default for a named instance) what do you do, well every time the port changes you need to change the SPN allocated to the account. Thats why its advised to let SQL Server register the SPN itself. You may also have thought, well what happens if I change my service account, won't that lead to two accounts with the same SPN. Possibly. Having two accounts with the same SPN is definitely a problem. Why? Well because if there are two accounts Kerberos can't identify the exact account that the service is running as, it could be either account, and so your security falls back to NTLM. SETSPN is useful for finding duplicate SPNs Reading this you will probably be thinking Oh my goodness this is really difficult. It is however I've found today in investigating something else that there is an easy option. Use Network Service as your service account. Network Service is a special account and is tied to the computer. It appears that Network Service has the update rights to AD to set an SPN mapping for the computer account. This then allows the SPN mapping to work. I believe this also works for the local system account. To get all the SPNs in your AD run the following, it could be a large file, so you might want to restrict it to a specific OU, or CN ldifde -d "DC=<domain>" -l servicePrincipalName -F spn.txt You will read in the links below that you need SQL to register the SPN this is done how to use Kerberos authenticaiton in SQL Server - http://support.microsoft.com/kb/319723 Using Kerberos with SQL Server - http://blogs.msdn.com/sql_protocols/archive/2005/10/12/479871.aspx Understanding Kerberos and NTLM authentication in SQL Server Connections - http://blogs.msdn.com/sql_protocols/archive/2006/12/02/understanding-kerberos-and-ntlm-authentication-in-sql-server-connections.aspx Summary The only reason I personally know to use a domain account is when you can't get kerberos to work and you want to do BULK INSERT or other network service that requires access to a a remote server. In this case you have to resort to using SQL authentication and the SQL Server uses its service account to access the remote service, and thus you need a domain account. You migth need this if using some forms of replication. I've always found Kerberos awkward to setup and so fallen back to this domain account approach. So in summary to get Kerberos to work try using the network service or local system accounts. For a great post from the Adam Saxton of the SQL Server support team go to http://blogs.msdn.com/psssql/archive/2010/03/09/what-spn-do-i-use-and-how-does-it-get-there.aspx 

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• BizTalk host throttling &ndash; Singleton pattern and High database size

  - by S.E.R.

  Originally posted on: http://geekswithblogs.net/SERivas/archive/2013/06/30/biztalk-host-throttling-ndash-singleton-pattern-and-high-database-size.aspxI have worked for some days around the singleton pattern (for those unfamiliar with it, read this post by Victor Fehlberg) and have come across a few very interesting posts, among which one dealt with performance issues (here, also by Victor Fehlberg). Simply put: if you have an orchestration which implements the singleton pattern, then performances will continuously decrease as the orchestration receives and consumes messages, and that behavior is more obvious when the orchestration never ends (ie : it keeps looping and never terminates or completes). As I experienced the same kind of problem (actually I was alerted by SCOM, which told me that the host was being throttled because of High database size), I thought it would be a good idea to dig a little bit a see what happens deep inside BizTalk and thus understand the reasons for this behavior. NOTE: in this article, I will focus on this High database size throttling condition. I will try and work on the other conditions in some not too distant future… Test conditions The singleton orchestration For the purpose of this study, I have created the following orchestration, which is a very basic implementation of a singleton that piles up incoming messages, then does something else when a certain timeout has been reached without receiving another message: Throttling settings I have two distinct hosts : one that hosts the receive port (basic FILE port) : Ports_ReceiveHostone that hosts the orchestration : ProcessingHost In order to emphasize the throttling mechanism, I have modified the throttling settings for each of these hosts are as follows (all other parameters are set to the default value): [Throttling thresholds] Message count in database: 500 (default value : 50000) Evolution of performance counters when submitting messages Since we are investigating the High database size throttling condition, here are the performance counter that we should take a look at (all of them are in the BizTalk:Message Agent performance object): Database sizeHigh database sizeMessage delivery throttling stateMessage publishing throttling stateMessage delivery delay (ms)Message publishing delay (ms)Message delivery throttling state durationMessage publishing throttling state duration (If you are not used to Perfmon, I strongly recommend that you start using it right now: it is a wonderful tool that allows you to open the hood and see what is going on inside BizTalk – and other systems) Database size It is quite obvious that we will start by watching the database size and high database size counters, just to see when the first reaches the configured threshold (500) and when the second rings the alarm. NOTE : During this test I submitted 600 messages, one message at a time every 10ms to see the evolution of the counters we have previously selected. It might not show very well on this screenshot, but here is what happened: From 15:46:50 to 15:47:50, the database size for the Ports_ReceiveHost host (blue line) kept growing until it reached a maximum of 504.At 15:47:50, the high database size alert fires At first I was surprised by this result: why is it the database size of the receiving host that keeps growing since it is the processing host that piles up messages? Actually, it makes total sense. This counter measures the size of the database queue that is being filled by the host, not consumed. Therefore, the high database size alert is raised on the host that fills the queue: Ports_ReceiveHost. More information is available on the Public MPWiki page. Now, looking at the Message publishing throttling state for the receiving host (green line), we can see that a throttling condition has been reached at 15:47:50: We can also see that the Message publishing delay(ms) (blue line) has begun growing slowly from this point. All of this explains why performances keep decreasing when a singleton keeps processing new messages: the database size grows and when it has exceeded the Message count in database threshold, the host is throttled and the publishing delay keeps increasing. Digging further So, what happens to the database queue then? Is it flushed some day or does it keep growing and growing indefinitely? The real question being: will the host be throttled forever because of this singleton? To answer this question, I set the Message count in database threshold to 20 (this value is very low in order not to wait for too long, otherwise I certainly would have fallen asleep in front of my screen) and I submitted 30 messages. The test was started at 18:26. At 18:56 (ie : exactly 30min later) the throttling was stopped and the database size was divided by 2. 30 min later again, the database size had dropped to almost zero: I guess I’ll have to find some documentation and do some more testing before I sort this out! My guess is that some maintenance job is at work here, though I cannot tell which one Digging even further If we take a look at the Message delivery throttling state counter for the processing host, we can see that this host was also throttled during the submission of the 600 documents: The value for the counter was 1, meaning that Message delivery incoming rate for the host instance exceeds the Message delivery outgoing rate * the specified Rate overdrive factor (percent) value. We will see this another day… :) A last word Let’s end this article with a warning: DO NOT CHANGE THE THROTTLING SETTINGS LIGHTLY! The temptation can be great to just bypass throttling by setting very high values for each parameter (or zero in some cases, which simply disables throttling). Nevertheless, always keep in mind that this mechanism is here for a very good reason: prevent your BizTalk infrastructure from exploding!! So whatever you do with those settings, do a lot of testing and benchmarking!

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• Performance considerations for common SQL queries

  - by Jim Giercyk

  Originally posted on: http://geekswithblogs.net/NibblesAndBits/archive/2013/10/16/performance-considerations-for-common-sql-queries.aspxSQL offers many different methods to produce the same results.  There is a never-ending debate between SQL developers as to the “best way” or the “most efficient way” to render a result set.  Sometimes these disputes even come to blows….well, I am a lover, not a fighter, so I decided to collect some data that will prove which way is the best and most efficient.  For the queries below, I downloaded the test database from SQLSkills:  http://www.sqlskills.com/sql-server-resources/sql-server-demos/.  There isn’t a lot of data, but enough to prove my point: dbo.member has 10,000 records, and dbo.payment has 15,554.  Our result set contains 6,706 records. The following queries produce an identical result set; the result set contains aggregate payment information for each member who has made more than 1 payment from the dbo.payment table and the first and last name of the member from the dbo.member table.   /*************/ /* Sub Query  */ /*************/ SELECT  a.[Member Number] ,         m.lastname ,         m.firstname ,         a.[Number Of Payments] ,         a.[Average Payment] ,         a.[Total Paid] FROM    ( SELECT    member_no 'Member Number' ,                     AVG(payment_amt) 'Average Payment' ,                     SUM(payment_amt) 'Total Paid' ,                     COUNT(Payment_No) 'Number Of Payments'           FROM      dbo.payment           GROUP BY  member_no           HAVING    COUNT(Payment_No) > 1         ) a         JOIN dbo.member m ON a.[Member Number] = m.member_no         /***************/ /* Cross Apply  */ /***************/ SELECT  ca.[Member Number] ,         m.lastname ,         m.firstname ,         ca.[Number Of Payments] ,         ca.[Average Payment] ,         ca.[Total Paid] FROM    dbo.member m         CROSS APPLY ( SELECT    member_no 'Member Number' ,                                 AVG(payment_amt) 'Average Payment' ,                                 SUM(payment_amt) 'Total Paid' ,                                 COUNT(Payment_No) 'Number Of Payments'                       FROM      dbo.payment                       WHERE     member_no = m.member_no                       GROUP BY  member_no                       HAVING    COUNT(Payment_No) > 1                     ) ca /********/                    /* CTEs  */ /********/ ; WITH    Payments           AS ( SELECT   member_no 'Member Number' ,                         AVG(payment_amt) 'Average Payment' ,                         SUM(payment_amt) 'Total Paid' ,                         COUNT(Payment_No) 'Number Of Payments'                FROM     dbo.payment                GROUP BY member_no                HAVING   COUNT(Payment_No) > 1              ),         MemberInfo           AS ( SELECT   p.[Member Number] ,                         m.lastname ,                         m.firstname ,                         p.[Number Of Payments] ,                         p.[Average Payment] ,                         p.[Total Paid]                FROM     dbo.member m                         JOIN Payments p ON m.member_no = p.[Member Number]              )     SELECT  *     FROM    MemberInfo /************************/ /* SELECT with Grouping   */ /************************/ SELECT  p.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         COUNT(Payment_No) 'Number Of Payments' ,         AVG(payment_amt) 'Average Payment' ,         SUM(payment_amt) 'Total Paid' FROM    dbo.payment p         JOIN dbo.member m ON m.member_no = p.member_no GROUP BY p.member_no ,         m.lastname ,         m.firstname HAVING  COUNT(Payment_No) > 1   We can see what is going on in SQL’s brain by looking at the execution plan.  The Execution Plan will demonstrate which steps and in what order SQL executes those steps, and what percentage of batch time each query takes.  SO….if I execute all 4 of these queries in a single batch, I will get an idea of the relative time SQL takes to execute them, and how it renders the Execution Plan.  We can settle this once and for all.  Here is what SQL did with these queries:   Not only did the queries take the same amount of time to execute, SQL generated the same Execution Plan for each of them.  Everybody is right…..I guess we can all finally go to lunch together!  But wait a second, I may not be a fighter, but I AM an instigator.     Let’s see how a table variable stacks up.  Here is the code I executed: /********************/ /*  Table Variable  */ /********************/ DECLARE @AggregateTable TABLE     (       member_no INT ,       AveragePayment MONEY ,       TotalPaid MONEY ,       NumberOfPayments MONEY     ) INSERT  @AggregateTable         SELECT  member_no 'Member Number' ,                 AVG(payment_amt) 'Average Payment' ,                 SUM(payment_amt) 'Total Paid' ,                 COUNT(Payment_No) 'Number Of Payments'         FROM    dbo.payment         GROUP BY member_no         HAVING  COUNT(Payment_No) > 1   SELECT  at.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         at.NumberOfPayments 'Number Of Payments' ,         at.AveragePayment 'Average Payment' ,         at.TotalPaid 'Total Paid' FROM    @AggregateTable at         JOIN dbo.member m ON m.member_no = at.member_no In the interest of keeping things in groupings of 4, I removed the last query from the previous batch and added the table variable query.  Here’s what I got:     Since we first insert into the table variable, then we read from it, the Execution Plan renders 2 steps.  BUT, the combination of the 2 steps is only 22% of the batch.  It is actually faster than the other methods even though it is treated as 2 separate queries in the Execution Plan.  The argument I often hear against Table Variables is that SQL only estimates 1 row for the table size in the Execution Plan.  While this is true, the estimate does not come in to play until you read from the table variable.  In this case, the table variable had 6,706 rows, but it still outperformed the other queries.  People argue that table variables should only be used for hash or lookup tables.  The fact is, you have control of what you put IN to the variable, so as long as you keep it within reason, these results suggest that a table variable is a viable alternative to sub-queries. If anyone does volume testing on this theory, I would be interested in the results.  My suspicion is that there is a breaking point where efficiency goes down the tubes immediately, and it would be interesting to see where the threshold is. Coding SQL is a matter of style.  If you’ve been around since they introduced DB2, you were probably taught a little differently than a recent computer science graduate.  If you have a company standard, I strongly recommend you follow it.    If you do not have a standard, generally speaking, there is no right or wrong answer when talking about the efficiency of these types of queries, and certainly no hard-and-fast rule.  Volume and infrastructure will dictate a lot when it comes to performance, so your results may vary in your environment.  Download the database and try it!

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• SQLAuthority News – Learning Trip – Traveling to Learn SQL Server

  - by pinaldave

  I am currently traveling to Delhi to learn SQL Server in person from my friend. You can read more details about why am I learning SQL Server.  I have signed up for the course End to End SQL Server Business Intelligence at Koenig Solutions. Yesterday I blogged about my registration experience and today I am going to write about my  experience once I arrived at Delhi. From Ahmedabad to Delhi I stay with my wife and daughter in Bangalore (IT Hub of India), my hometown is Ahmedabad. My parents stay in city nearby Ahmedabad. I decided to spend few days with my folks before I sign up for 3 days of solid learning. I had selected an early morning flight to Delhi. I landed at 8:30 AM in Delhi. As soon as I checked email in my mobile I was really glad that I had received details of my pick up vehicle from Koenig. I walked out of the airport and I noticed that a driver was waiting with a placard with my name and photo associated with it. He was in Koenig uniform so there was no chance to make mistakes. In minutes of landing in Delhi I was in my transport heading to the Koenig Training Center. After the quick introduction driver handed me a bag (to be precise Eco friendly bag). The bag contained following items: My registration form All necessary documents in print which I had received earlier A Printed Book of the course next day INR 1000 (What?) I was glad to receive the bag but I was very confused with the Rs 1000. I decided to figure this out once I reach to the training center. Arriving at Koenig Inn Deluxe Koenig registration fees include all the stay and meals. I had opted for Koenig Inn Deluxe as my stay as it was recommended by my friend as well it was the right economical choice for me. When I reached to my accommodation, they were well aware of my arrival and was immediately led to my spacious room. The room is well equipped with all the amenities (hot water, air condition, coffee table, munching snacks,  and free internet) and the staff is very friendly. I immediately got ready as I had to go to Koenig Training Center to meet Center Head for a quick introduction. Koenig Inn Delux Koenig Training Center The training center is within five minutes of distance from the accommodation. I was lead to center head right away and had a very meaningful conversation with Ms Hema regarding my learning goals. She gave me a quick tour of the training center. I was amazed with the numbers of lab rooms they have in the center. The labs are spacious and give the most needed hand’s on experience to the users. I was led to the lab where I was suppose to learn my class the very next day as well I was provided my trainer’s profile. Mystery of Rs 1000 Well, after all this I have still not forgotten why I was provided Rs 1000 when arrived at the airport. When I asked about that I was told that because many students comes from foreign places and they may not have Indian Currency when they land at airport. This was for their immediate consumption till they arrive at the training center. Later on they can get their currency converted to local currency at Koenig Travel Desk. My curiosity was satisfied but I had not expected this answer. I am amazed at the attention to the details. Koenig Travel Desk When I heard about Koenig Travel Desk, I remembered that I have few friends in Delhi and Gurgaon. I had completed all of the formalities so I had reset of the day on my hand. I requested the travel desk if they can arrange a day cab for me so I can visit my friends in Guragon. Within 10 minutes I was on my way to Gurgaon. Telerik India Office Visit What did I do in Guragaon? I met my friends Abhishek Kant, Dhananjay Kumar and Amit Chowdhary. I visited Telerik India office and we had an excellent conversation on various aspects of technology and community. The Telerik India office is very spacious and Abhishek Kant (Telerik India Country Manager) gave us a quick tour of the office. We had an excellent lunch and dinner. One thing is for sure – the day was well spent. Pinal Dave, Dhananjay Kumar and Abhishek Kant Later evening I returned to my accommodation and decided to read up a few of the topics which I was going to learn next day. In tomorrow’s blog post I will discuss about my learning experience. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Training, T SQL, Technology

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• Windows Phone 7 development: first impressions

  - by DigiMortal

  After hard week in work I got some free time to play with Windows Phone 7 CTP developer tools. Although my first test application is still unfinished I think it is good moment to share my first experiences to you. In this posting I will give you quick overview of Windows Phone 7 developer tools from developer perspective. If you are familiar with Visual Studio 2010 then you will feel comfortable because Windows Phone 7 CTP developer tools base on Visual Studio 2010 Express. Project templates There are five project templates available. Three of them are based on Silverlight and two on XNA Game Studio: Windows Phone Application (Silverlight) Windows Phone List Application (Silverlight) Windows Phone Class Library (Silverlight) Windows Phone Game (XNA Game Studio) Windows Phone Game Library (XNA Game Studio) Currently I am writing to test applications. One of them is based on Windows Phone Application and the other on Windows Phone List Application project template. After creating these projects you see the following views in Visual Studio. Windows Phone Application. Click on image to enlarge. Windows Phone List Application. Click on image to enlarge.  I suggest you to use some of these templates to get started more easily. Windows Phone 7 emulator You can run your Windows Phone 7 applications on Windows Phone 7 emulator that comes with developer tools CTP. If you run your application then emulator is started automatically and you can try out how your application works in phone-like emulator. You can see screenshot of emulator on right. Currently there is opened Windows Phone List Application as it is created by default. Click on image to enlarge it. Emulator is a little bit slow and uncomfortable but it works pretty well. This far I have caused only couple of crashes during my experiments. In these cases emulator works but Visual Studio gets stuck because it cannot communicate with emulator. One important note. Emulator is based on virtual machine although you can see only phone screen and options toolbar. If you want to run emulator you must close all virtual machines running on your machine and run Visual Studio 2010 as administrator. Once you run emulator you can keep it open because you can stop your application in Visual Studio, modify, compile and re-deploy it without restarting emulator. Designing user interfaces You can design user interface of your application in Visual Studio. When you open XAML-files it is displayed in window with two panels. Left panel shows you device screen and works as visual design environment while right panel shows you XAML mark-up and let’s you modify XML if you need it. As it is one of my very first Silverlight applications I felt more comfortable with XAML editor because property names in property boxes of visual designer confused me a little bit. Designer panel is not very good because it is visually hard to follow. It has black background that makes dark borders of controls very hard to see. If you have monitor with very high contrast then it is may be not a real problem. I have usual monitor and I have problem. :) Putting controls on design surface, dragging and resizing them is also pretty painful. Some controls are drawn correctly but for some controls you have to set width and height in XML so they can be resized. After some practicing it is not so annoying anymore. On the right you can see toolbox with some controllers. This is all you get out of the box. But it is sufficient to get started. After getting some experiences you can create your own controls or use existing ones from other vendors or developers. If it is your first time to do stuff with Silverlight then keep Google open – you need it hard. After getting over the first shock you get the point very quickly and start developing at normal speed. :) Writing source code Writing source code is the most familiar part of this action. Good old Visual Studio code editor with all nice features it has. But here you get also some surprises: The anatomy of Silverlight controls is a little bit different than the one of user controls in web and forms projects. Windows Phone 7 doesn’t run on full version of Windows (I bet it is some version of Windows CE or something like this) then there is less system classes you can use. Some familiar classes have less methods that in full version of .NET Framework and in these cases you have to write all the code by yourself or find libraries or source code from somewhere. These problems are really not so much problems than limitations and you get easily over them. Conclusion Windows Phone 7 CTP developer tools help you do a lot of things on Windows Phone 7. Although I expected better performance from tools I think that current performance is not a problem. This far my first test project is going very well and Google has answer for almost every question. Windows Phone 7 is mobile device and therefore it has less hardware resources than desktop computers. This is why toolset is so limited. The more you need memory the more slower is device and as you may guess it needs the more battery. If you are writing apps for mobile devices then make your best to get your application use as few resources as possible and act as fast as possible.

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• jQuery Datatable in MVC &hellip; extended.

  - by Steve Clements

  There are a million plugins for jQuery and when a web forms developer like myself works in MVC making use of them is par-for-the-course!  MVC is the way now, web forms are but a memory!! Grids / tables are my focus at the moment.  I don’t want to get in to righting reems of css and html, but it’s not acceptable to simply dump a table on the screen, functionality like sorting, paging, fixed header and perhaps filtering are expected behaviour.  What isn’t always required though is the massive functionality like editing etc you get with many grid plugins out there. You potentially spend a long time getting everything hooked together when you just don’t need it. That is where the jQuery DataTable plugin comes in.  It doesn’t have editing “out of the box” (you can add other plugins as you require to achieve such functionality). What it does though is very nicely format a table (and integrate with jQuery UI) without needing to hook up and Async actions etc.  Take a look here… http://www.datatables.net I did in the first instance start looking at the Telerik MVC grid control – I’m a fan of Telerik controls and if you are developing an in-house of open source app you get the MVC stuff for free…nice!  Their grid however is far more than I require.  Note: Using Telerik MVC controls with your own jQuery and jQuery UI does come with some hurdles, mainly to do with the order in which all your jQuery is executing – I won’t cover that here though – mainly because I don’t have a clear answer on the best way to solve it! One nice thing about the dataTable above is how easy it is to extend http://www.datatables.net/examples/plug-ins/plugin_api.html and there are some nifty examples on the site already… I however have a requirement that wasn’t on the site … I need a grid at the bottom of the page that will size automatically to the bottom of the page and be scrollable if required within its own space i.e. everything above the grid didn’t scroll as well.  Now a CSS master may have a great solution to this … I’m not that master and so didn’t! The content above the grid can vary so any kind of fixed positioning is out. So I wrote a little extension for the DataTable, hooked that up to the document.ready event and window.resize event. Initialising my dataTable ( s )… $(document).ready(function () {   var dTable = $(".tdata").dataTable({ "bPaginate": false, "bLengthChange": false, "bFilter": true, "bSort": true, "bInfo": false, "bAutoWidth": true, "sScrollY": "400px" });   My extension to the API to give me the resizing….   // ********************************************************************** // jQuery dataTable API extension to resize grid and adjust column sizes // $.fn.dataTableExt.oApi.fnSetHeightToBottom = function (oSettings) { var id = oSettings.nTable.id; var dt = $("#" + id); var top = dt.position().top; var winHeight = $(document).height(); var remain = (winHeight - top) - 83; dt.parent().attr("style", "overflow-x: auto; overflow-y: auto; height: " + remain + "px;"); this.fnAdjustColumnSizing(); } This is very much is debug mode, so pretty verbose at the moment – I’ll tidy that up later! You can see the last call is a call to an existing method, as the columns are fixed and that normally involves so CSS voodoo, a call to adjust those sizes is required. Just above is the style that the dataTable gives the grid wrapper div, I got that from some firebug action and stick in my new height. The –83 is to give me the space at the bottom i require for fixed footer!   Finally I hook that up to the load and window resize.  I’m actually using jQuery UI tabs as well, so I’ve got that in the open event of the tabs.   $(document).ready(function () { var oTable; $("#tabs").tabs({ "show": function (event, ui) { oTable = $('div.dataTables_scrollBody>table.tdata', ui.panel).dataTable(); if (oTable.length > 0) { oTable.fnSetHeightToBottom(); } } }); $(window).bind("resize", function () { oTable.fnSetHeightToBottom(); }); }); And that all there is too it.  Testament to the wonders of jQuery and the immense community surrounding it – to which I am extremely grateful. I’ve also hooked up some custom column filtering on the grid – pretty normal stuff though – you can get what you need for that from their website.  I do hide the out of the box filter input as I wanted column specific, you need filtering turned on when initialising to get it to work and that input come with it!  Tip: fnFilter is the method you want.  With column index as a param – I used data tags to simply that one.

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• FAT Volume and CE

  - by Kate Moss' Open Space

  Whenever we format a disk volume, it is a good idea to name the label so it will be easier to categorize. To label a volume, we can use LABEL command or UI depends on your preference. Windows CE does provide FAT driver and support various format (FAT12, FAT16,FAT32, ExFAT and TFAT - transaction-safe FAT) and many feature to let you scan and even defrag the volume but not labeling. At any time you format a volume in CE and then mount it on PC, the label is always empty! Of course, you can always label the volume on PC, even it is formatted in CE. So looks like CE does not care about the volume label at all, neither report the label to OS nor changing the label on FAT.So how can we set the volume label in CE? To Answer this question, we need to know how does FAT stores the volume label. Here are some on-line resources are handy for parsing FAT. http://en.wikipedia.org/wiki/File_Allocation_Table http://www.pjrc.com/tech/8051/ide/fat32.html http://www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx You can refer to PUBLIC\COMMON\OAK\DRIVERS\FSD\FATUTIL\MAIN\bootsec.h and dosbpb.h or the above links for the fields we discuss here. The first sector of a FAT Volume (it is not necessary to be the first sector of a disk.) is a FAT boot sector and BPB (BIOS Parameter Block). And at offset 43, bgbsVolumeLabel (or bsVolumeLabel on FAT16) is for storing the volume lable, but note in the spec also indicates "FAT file system drivers should make sure that they update this field when the volume label file in the root directory has its name changed or created.". So we can't just simply update the bgbsVolumeLabel but also need to create a volume lable file in root directory. The volume lable file is not a real file but just a file entry in root directory with zero file lenth and a very special file attribute, ATTR_VOLUME_ID. (defined in public\common\oak\drivers\fsd\fatutil\MAIN\fatutilp.h) Locating and accessing bootsector is quite straight forward, as long as we know the starting sector of a FAT volume, that's it. But where is the root directory? The layout of a typical FAT is like this Boot sector (Volume ID in the figure) followed by Reserved Sectors (1 on FAT12/16 and 32 on FAT32), then FAT chain table(s) (can be 1 or 2), after that is the root directory (FAT12/16 and not shows in the figure) then begining of the File and Directories. In FAT12/16, the root directory is placed right after FAT so it is not hard to caculate the offset in the volume. But in FAT32, this rule is no longer true: the first cluster of the root directory is determined by BGBPB_RootDirStrtClus (or offset 44 in boot sector). Although this field is usually 0x00000002 (it is how CE initial the root directory after formating a volume. Note we should never assume it is always true) which means the first cluster contains data but not like the root directory is contiguous in FAT12/16, it is just like a regular file can be fragmented. So we need to access the root directory (of FAT32) hopping one cluster to another by traversing FAT table. Let's trace the code now. Although the source of FAT driver is not available in CE Shared Source program, but the formatter, Fatutil.dll, is available in public\common\oak\drivers\fsd\fatutil\MAIN\formatdisk.cpp. Be aware the public code only provides formatter for FAT12/16/32 for ExFAT it is still not available. FormatVolumeInternal is the main worker function. With the knowledge here, you should be able the trace the code easily. But I would like to discuss the following code pieces     dwReservedSectors = (fo.dwFatVersion == 32) ? 32 : 1;     dwRootEntries = (fo.dwFatVersion == 32) ? 0 : fo.dwRootEntries; Note the dwReservedSectors is 32 in FAT32 and 1 in FAT12/16. Root Entries is another different mentioned in previous paragraph, 0 for FAT32 (dynamic allocated) and fixed size (usually 512, defined in DEFAULT_ROOT_ENTRIES in public\common\sdk\inc\fatutil.h) And then here   memset(pBootSec->bsVolumeLabel, 0x20, sizeof(pBootSec->bsVolumeLabel)); It sets the Volume Label as empty string. Now let's carry on to the next section - write the root directory.     if (fo.dwFatVersion == 32) {         if (!(fo.dwFlags & FATUTIL_FORMAT_TFAT)) {             dwRootSectors = dwSectorsPerCluster;         }         else {             DIRENTRY    dirEntry;             DWORD       offset;             int               iVolumeNo;             memset(pbBlock, 0, pdi->di_bytes_per_sect);             memset(&dirEntry, 0, sizeof(DIRENTRY));                         dirEntry.de_attr = ATTR_VOLUME_ID;             // the first one is volume label             memcpy(dirEntry.de_name, "TFAT       ", sizeof (dirEntry.de_name));             memcpy(pbBlock, &dirEntry, sizeof(dirEntry));              ...             // Skip the next step of zeroing out clusters             dwCurrentSec += dwSectorsPerCluster;             dwRootSectors = 0;         }     }     // Each new root directory sector needs to be zeroed.     memset(pbBlock, 0, cbSizeBlk);     iRootSec=0;     while ( iRootSec < dwRootSectors) { Basically, the code zero out the each entry in root directory depends on dwRootSectors. In FAT12/16, the dwRootSectors is calculated as the sectors we need for the root entries (512 for most of the case) and in FAT32 it just zero out the one cluster. Please note that, if it is a TFAT volume, it initialize the root directory with special volume label entries for some special purpose. Despite to its unusual initialization process for TFAT, it does provide a example for how to create a volume entry. With some minor modification, we can assign the volume label in FAT formatter and also remember to sync the volume label with bsVolumeLabel or bgbsVolumeLabel in boot sector.

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• ISO Files to USB &ndash; The Cheap and Easy Way

  - by RonGarlit

  (DISCLAIMER: Yes there are lots of more elegant ISO software beside the free Microsoft one I’m about to show. But free is free and it has been tested and works for me for making advance bootable USB drives. That is another story. Look up Windows 8 Developer Preview for that one on BING.) For those of use that work with new technology all the time we accumulate a lot of ISO files and have to burn them to CD/DVD’s quite often. But we now have machines without burner in the corporate environment. We have personally Netbooks and light wait highly mobile laptops that do not have DVD burner. USB ports are all the rage and now we have USB 3.0 which is way faster than the 2.0 we are used to. Just looking at the technology, space saving and the cost issues alone is a reason to buy these answer to the DVD’s. So what is special about USB 2.0 and USB 3.0? USB 2 has a maximum speed of 480 Mbps... (That is Megabits per SECOND!!) Now look at the storage that we have with USB thumb drives that are now up to 64 GB in size, cell phone and PDAs that have a lots of internal storage built in well above the 16 Gig range. At the MAX USB 2.0 speed of 480 Mbps a full transfer of data in between devices can take a long time. Time is money right. Every back up a iPhone? Don’t get me started. So at least the engineers have been planning ahead with USB 3.0 which offers a maximum transfer speed of 4.8 Gbps... (That is Giga bits per SECOND!!) That speed is almost 10 times faster than USB 2.0 …. We don’t need to do the math on that one do we? But for now I'm thrilled with USB 2.0 and the fact I can get these little 4 Gig USB drives for $4.00 each at Staples on sale. Well that is a no brainer don’t you think. But what can you do with them to replace that DVD. Simply and cheaply put………. THIS! First let’s get an ISO file like the Visual Studio 2010 Ultimate DVD ISO from MSDN to demonstrate with. I develop on several computers so this is a good choice for me. So we downloaded the ISO file and put it in a folder somewhere like this. Next we go download to the Windows 7 USB/DVD Download Tool site and read about the tool. http://www.microsoftstore.com/store/msstore/html/pbPage.Help_Win7_usbdvd_dwnTool And click this like to get the tool and install it. Once it is installed you go to the Start, Programs menu, Windows 7 USB DVD Download Tool folder. And then click the tool to open it up. As you will see it is a sweet, simple tool that was originally designed to put the ISO for Windows 7 which is designed to be bootable on a USB or DVD for us geeks to play with. It is now being used for the Windows 8 Developer Preview by many developers for that for the same purpose it was built for in the past. But for now we will use it to put a NON Bootable ISO on a USB. Hey it does the job and I’m reusing a left over program. Why buy the fancy one or a free trial and clutter up my machine. We will click the BROWSE button and navigate to where we put our ISO file we want to put on the USB drive. Obviously we are going to click NEXT and continue to select a USB Device (you can guess what the DVD button is for). Next we select the USB that we have plugged into one of our laptops USB ports. Then we click the BEGIN COPYING button and the first thing the program does is format our USB drive. Then it starts copying out files out of the ISO and constructing the USB as if it was a DVD. So now that the files are copying to the drive I’m going to warn you. We will error out here. This program was design for bootable ISO’s of which this one is NOT. No problem because what fails it the writing of the bootable data to the drive that isn’t there. No biggie…. Forget the STARTOVER button is even there and click the dialog’s CLOSE button and exit the program. Now go to Windows Explorer and navigate to the USB Device. You can now access everything and even add stuff to the drive. But for me I want to keep this drive for one purpose and that is to install VS2010 on various machines. So the only stuff I’ll add to this is a folder of notes on things on visual studio that I might want to put on other machines I’m installing VS2010 on to. So that is it. Have a nice day! The Ron

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• Minidlna Directory Issues

  - by Somnambulist

  I've done my searching and can't find an answer to THIS specific issue. I have my minidlna set up and running - but it's not really done properly. First off, when I open the server on my bluray player, all of my movies are listed twice - when they are certainly not saved on my external twice. Second, when I open the server - rather than reading "Movies" "TV" "Music", etc - It just mashes all of my movies, tv, and some other folders all together with no real organization. I never had this problem when I had my Windows set up, so I know it's something configured improperly more-so than my external drive giving me gruff. Here's my minidlna.conf file: # This is the configuration file for the MiniDLNA daemon, a DLNA/UPnP-AV media # server. # # Unless otherwise noted, the commented out options show their default value. # # On Debian, you can also refer to the minidlna.conf(5) man page for # documentation about this file. media_dir=/media/somnambulist/Ghost In You # This option can be specified more than once if you want multiple directories # scanned. # # If you want to restrict a media_dir to a specific content type, you can # prepend the directory name with a letter representing the type (A, P or V), # followed by a comma, as so: # * "A" for audio (eg. media_dir=A,/var/lib/minidlna/music) # * "P" for pictures (eg. media_dir=P,/var/lib/minidlna/pictures) # * "V" for video (eg. media_dir=V,/var/lib/minidlna/videos) # # WARNING: After changing this option, you need to rebuild the database. Either # run minidlna with the '-R' option, or delete the 'files.db' file # from the db_dir directory (see below). # On Debian, you can run, as root, 'service minidlna force-reload' instead. #media_dir=/var/lib/minidlna media_dir=V,/media/somnambulist/Ghost In You/Movies media_dir=V,/media/somnambulist/Ghost In You/TV media_dir=P,/home/somnambulist/Pictures # Path to the directory that should hold the database and album art cache. db_dir=/home/somnambulist/serverart # Path to the directory that should hold the log file. log_dir=/home/somnambulist/serverlog # Minimum level of importance of messages to be logged. # Must be one of "off", "fatal", "error", "warn", "info" or "debug". # "off" turns of logging entirely, "fatal" is the highest level of importance # and "debug" the lowest. #log_level=warn # Use a different container as the root of the directory tree presented to # clients. The possible values are: # * "." - standard container # * "B" - "Browse Directory" # * "M" - "Music" # * "P" - "Pictures" # * "V" - "Video" # if you specify "B" and client device is audio-only then "Music/Folders" will be used as root root_container=B # Network interface(s) to bind to (e.g. eth0), comma delimited. #network_interface= # IPv4 address to listen on (e.g. 192.0.2.1). #listening_ip= # Port number for HTTP traffic (descriptions, SOAP, media transfer). port=8200 # URL presented to clients. # The default is the IP address of the server on port 80. #presentation_url=http://example.com:80 # Name that the DLNA server presents to clients. friendly_name=Somnambulist Media Server # Serial number the server reports to clients. serial=12345678 # Model name the server reports to clients. #model_name=Windows Media Connect compatible (MiniDLNA) # Model number the server reports to clients. model_number=1 # Automatic discovery of new files in the media_dir directory. #inotify=yes # List of file names to look for when searching for album art. Names should be # delimited with a forward slash ("/"). album_art_names=Cover.jpg/cover.jpg/AlbumArtSmall.jpg/albumartsmall.jpg/AlbumArt.jpg/albumart.jpg/Album.jpg/album.jpg/Folder.jpg/folder.jpg/Thumb.jpg/thumb.jpg # Strictly adhere to DLNA standards. # This allows server-side downscaling of very large JPEG images, which may # decrease JPEG serving performance on (at least) Sony DLNA products. #strict_dlna=no # Support for streaming .jpg and .mp3 files to a TiVo supporting HMO. #enable_tivo=no # Notify interval, in seconds. #notify_interval=895 # Path to the MiniSSDPd socket, for MiniSSDPd support. #minissdpdsocket=/run/minissdpd.sock` And here's the error I get in terminal when I run: sudo service minidlna restart sudo service minidlna force-reload Force restart error: Restarting DLNA/UPnP-AV media server minidlna [2013/08/12 21:19:27] minidlna.c:474: error: Media directory "/media/somnambulist/Ghost In You/Movies" not accessible! [Permission denied] [2013/08/12 21:19:27] minidlna.c:474: error: Media directory "/media/somnambulist/Ghost In You/TV" not accessible! [Permission denied] Force-reload error: Restarting DLNA/UPnP-AV media server minidlna [2013/08/12 21:19:46] minidlna.c:474: error: Media directory "/media/somnambulist/Ghost In You/Movies" not accessible! [Permission denied] [2013/08/12 21:19:46] minidlna.c:474: error: Media directory "/media/somnambulist/Ghost In You/TV" not accessible! [Permission denied] rm: cannot remove ‘/home/somnambulist/serverart/files.db’: Permission denied rm: cannot remove ‘/home/somnambulist/serverart/art_cache/media/somnambulist/Ghost In You/Movies/Slumdog Millionaire/Slumdog.Millionaire.Cover.jpg’: Permission denied rm: cannot remove ‘/home/somnambulist/serverart/art_cache/media/somnambulist/Ghost In You/Movies/Zack and Miri Make a Porno/ZackAndMiriMakeAPornoCover.jpg’: Permission denied [2013/08/12 21:19:46] minidlna.c:744: warn: Failed to clean old file cache. [ OK ] I've spent hours on this at this point, read through various files - and even had a friend who is relatively Ubuntu-savvy try to help me via chat - no such luck. Thanks in advance for any help.

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• Identity Management Monday at Oracle OpenWorld

  - by Tanu Sood

  What a great start to Oracle OpenWorld! Did you catch Larry Ellison’s keynote last evening? As expected, it was a packed house and the keynote received a tremendous response both from the live audience as well as the online community as evidenced by the frequent spontaneous applause in house and the twitter buzz. Here’s but a sampling of some of the tweets that flowed in: @paulvallee: I freaking love that #oracle has been born again in it's interest in core tech #oow (so good for #pythian) @rwang0: MyPOV: #oracle just leapfrogged the competition on the tech front across the board. All they need is the content delivery network #oow12 @roh1: LJE more astute & engaging this year. Nice announcements this year with 12c the MTDB sounding real good. #oow12 @brooke: Cool to see @larryellison interrupted multiple times by applause from the audience. Great speaker. #OOW And there’s lot more to come this week. Identity Management sessions kick-off today. Here’s a quick preview of what’s in store for you today for Identity Management: CON9405: Trends in Identity Management 10:45 a.m. – 11:45 a.m., Moscone West 3003 Hear directly from subject matter experts from Kaiser Permanente and SuperValu who would share the stage with Amit Jasuja, Senior Vice President, Oracle Identity Management and Security, to discuss how the latest advances in Identity Management that made it in Oracle Identity Management 11g Release 2 are helping customers address emerging requirements for securely enabling cloud, social and mobile environments. CON9492: Simplifying your Identity Management Implementation 3:15 p.m. – 4:15 p.m., Moscone West 3008 Implementation experts from British Telecom, Kaiser Permanente and UPMC participate in a panel to discuss best practices, key strategies and lessons learned based on their own experiences. Attendees will hear first-hand what they can do to streamline and simplify their identity management implementation framework for a quick return-on-investment and maximum efficiency. This session will also explore the architectural simplifications of Oracle Identity Governance 11gR2, focusing on how these enhancements simply deployments. CON9444: Modernized and Complete Access Management 4:45 p.m. – 5:45 p.m., Moscone West 3008 We have come a long way from the days of web single sign-on addressing the core business requirements. Today, as technology and business evolves, organizations are seeking new capabilities like federation, token services, fine grained authorizations, web fraud prevention and strong authentication. This session will explore the emerging requirements for access management, what a complete solution is like, complemented with real-world customer case studies from ETS, Kaiser Permanente and TURKCELL and product demonstrations. HOL10478: Complete Access Management Monday, October 1, 1:45 p.m. – 2:45 p.m., Marriott Marquis - Salon 1/2 And, get your hands on technology today. Register and attend the Hands-On-Lab session that demonstrates Oracle’s complete and scalable access management solution, which includes single sign-on, authorization, federation, and integration with social identity providers. Further, the session shows how to securely extend identity services to mobile applications and devices—all while leveraging a common set of policies and a single instance. Product Demonstrations The latest technology in Identity Management is also being showcased in the Exhibition Hall so do find some time to visit our product demonstrations there. Experts will be at hand to answer any questions. DEMOS LOCATION EXHIBITION HALL HOURS Access Management: Complete and Scalable Access Management Moscone South, Right - S-218 Monday, October 1 9:30 a.m.–6:00 p.m. 9:30 a.m.–10:45 a.m. (Dedicated Hours) Tuesday, October 2 9:45 a.m.–6:00 p.m. 2:15 p.m.–2:45 p.m. (Dedicated Hours) Wednesday, October 3 9:45 a.m.–4:00 p.m. 2:15 p.m.–3:30 p.m. (Dedicated Hours) Access Management: Federating and Leveraging Social Identities Moscone South, Right - S-220 Access Management: Mobile Access Management Moscone South, Right - S-219 Access Management: Real-Time Authorizations Moscone South, Right - S-217 Access Management: Secure SOA and Web Services Security Moscone South, Right - S-223 Identity Governance: Modern Administration and Tooling Moscone South, Right - S-210 Identity Management Monitoring with Oracle Enterprise Manager Moscone South, Right - S-212 Oracle Directory Services Plus: Performant, Cloud-Ready Moscone South, Right - S-222 Oracle Identity Management: Closed-Loop Access Certification Moscone South, Right - S-221 We recommend you keep the Focus on Identity Management document handy. And don’t forget, if you are not on site, you can catch all the keynotes LIVE from the comfort of your desk on YouTube.com/Oracle. Keep the conversation going on @oracleidm. Use #OOW and #IDM and get engaged today. Photo Courtesy: @OracleOpenWorld

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• SQL Saturday #44 Huntington Beach Recap

  What a great day. It was long and tiring, but rewarding in so many ways. On Sunday morning, I was driving home and I decided to take the Pacific Coast Highway from Huntington Beach.  It was a great chance to exhale and just enjoy the sun and smells of the beach (I really love SoCal sometimes). And for future reference for all you speakers, the beach and ocean are only 5 minutes from the SQL Saturday location.  I just could help noticing also the shocking number of high priced cars on the road (4 Bentleys, 3 Ferraris, 1 Aston Martins, 3 Maserati, 1 Rolls Royce, and 2 Lamborghinis).  It made me think about this: Price of all those cars: $ 150,000+.  Impacting the ability of people to learn: Priceless.  We have positively impacted the education, knowledge, capabilities of not only our attendees, but also all of their companies and people they might help as well.  That is just staggering and something to be immensely proud of. To all of my fellow community leaders, I salute you. So lets talk about the event Overall We had over 220 people register for the event and had 180+ people attend the event. I was shooting for the magical 200 number, but I guess it just gives us more motivation to make it even bigger and better next time. We had a few snags along the way, but what event doesnt, but I think everything turned out great. I did not hear any negative comments and heard lots of positive comments along with people asking when the next one is going to be (More on that later). Location- Golden West College We could not have asked for a better partner for the event. Herb Cohen from Golden West College was the wizard behind the curtains. From the beginning, he was our advocate to the GWC Board and was instrumental in getting our event approved. The day off, Herb was a HUGE help getting any and all logistics that we needed taken care of. In the craziness of the early morning registration crush it was a big help knowing that he and Bret Stateham (Blog | Twitter) were taking care of testing projectors in all the rooms. Anything we needed he was there and was even proactive in getting some things that I had not even thought of (i.e. a dumpster for all of our garbage). I cannot thank Herb enough along with other members of the GWC staff including Minnie Higgins of the Career and Technical Education Division office, Jack Taylor, public safety, and Ron Pryor, Tech Services Support. And last, but not least, the Wireless on campus was absolutely FANTASTIC! Some lessons learned Unless you are a glutton for punishment, as I no doubt am, you most certainly want to give yourself more than six weeks to plan the event. I am lucky that I have a very understanding wife and had a wonderful set of co-coordinators helping me out. A big thanks goes out to Phil, Marlon (Blog | Twitter), Nitin (Twitter), Thomas (Blog | Twitter), Bret (Blog | Twitter), Ben, and Laurie. Thankfully, the sponsor and speaker community was hugely supportive and we were able to fill out the entire event with speakers and sponsors. I have to say that there is not a lot that I would change after this years event. There are obviously going to be some things that we can do better or differently next time, but overall I think it was a great event and I was more than happy with the response we received from the community. Sponsors We obviously could not have put together our event without our sponsors. So certainly have to show them some love. Platinum Sponsors Quest Software http://www.quest.com My Space http://www.myspace.com/ Gold Strategy Companion http://www.strategycompanion.com Silver Fusion-IO http://www.fusionio.com Bronze WestClinTech http://westclintech.com Professional Association For SQL Server http://www.sqlpass.org Attunity http://www.attunity.com Sharepoint 360 http://www.sharepoint360.com Some additional Thanks Andy Warren (Blog | Twitter) Always there to answer my question and help out when I had some issues or questions with the website. The amount of work that he and everyone else put into SQL Saturday is very amazing. What a great gift to the community! Einstein Bros. Bagels They were our Breakfast Vendor and arrived perfectly on time with yummy bagels, sweets and most importantly coffee. Luccis Deli (http://www.luccisdeli.com) Luccis was out Lunch Vendor. They were great to work with and the food was excellent. They worked with us to give us a great price. Heard lots of great comments about the lunches. Definitely not your ordinary box lunch. Moving Forward Unfortunately, the work does not end after the event. We have a few things to clear up such as surveys, sponsor stuff, presentations uploaded to the website, expense reimbursement, stuff like that. Hopefully, all that should be cleared up within the next couple weeks. After that as a group we are going to get together and decide what our next steps are. We definitely want to keep some of the momentum that we are building as a SQL Community and channel that into future SQL Saturdays and other types of community events. In the meantime, for additional training be sure to check out your local User Group and PASS. San Diego SQL Server Users Group ( http://www.sdsqlug.org/home/index.cfm ) Orange County SQL Server Users Group ( http://www.sqloc.com/ ) L.A. SQL Server Users Group ( http://www.sql.la/ ) SQL PASS ( http://www.sqlpass.org/ ) 24 Hours of PASS ( http://www.sqlpass.org/24hours/2010/ ) So stay tuned, there will be more events to come in SoCal!!Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• IOUG and Oracle Enterprise Manager User Community Twitter Chat and Sessions at OpenWorld

  - by Anand Akela

  Like last many years, we will have annual Oracle Users Forum on Sunday, September 30th, 2012 at Moscone West, Levels 2 & 3 . It will be open to all registered attendees of Oracle Open World and conferences running from September 29 to October 5, 2012 . This will be a great  opportunity to meet with colleagues, peers, and subject matter experts to share best practices, tips, and techniques around Oracle technologies. You could sit in on a special interest group (SIG) meeting or session and learn how to get more out of Oracle technologies and applications. IOUG and Oracle Enterprise Manager team invites you to join a Twitter Chat on Sunday, Sep. 30th from 11:30 AM to 12:30 PM.  IOUG leaders, Enterprise Manager SIG contributors and many Oracle Users Forum speakers will answer questions related to their experience with Oracle Enterprise Manager and the activities and resources available for  Enterprise Manager SIG members. You can participate in the chat using hash tag #em12c on Twitter.com or by going to  tweetchat.com/room/em12c      (Needs Twitter credential for participating).  Feel free to join IOUG and Enterprise team members at the User Group Pavilion on 2nd Floor, Moscone West. Here is the complete list of Oracle Enterprise Manager sessions during the Oracle Users Forum : Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Time Session Title Speakers Location 8:00AM - 8:45AM UGF4569 - Oracle RAC Migration with Oracle Automatic Storage Management and Oracle Enterprise Manager 12c VINOD Emmanuel -Database Engineering, Dell, Inc. Wendy Chen - Sr. Systems Engineer, Dell, Inc. Moscone West - 2011 8:00AM - 8:45AM UGF10389 -  Monitoring Storage Systems for Oracle Enterprise Manager 12c Anand Ranganathan - Product Manager, NetApp Moscone West - 2016 9:00AM - 10:00AM UGF2571 - Make Oracle Enterprise Manager Sing and Dance with the Command-Line Interface Ray Smith - Senior Database Administrator, Portland General Electric Moscone West - 2011 10:30AM - 11:30AM UGF2850 - Optimal Support: Oracle Enterprise Manager 12c Cloud Control, My Oracle Support, and More April Sims - DBA, Southern Utah University Moscone West - 2011 11:30AM - 12:30PM IOUG and Oracle Enterprise Manager Joint Tweet Chat  Join IOUG Leaders, IOUG's Enterprise Manager SIG Contributors and Speakers on Twitter and ask questions related to practitioner's experience with Oracle Enterprise Manager and the new IOUG 's Enterprise Manager SIG. To attend and participate in the chat, please use hash tag #em12c on twitter.com or your favorite Twitter client. You can also go to tweetchat.com/room/em12c to watch the conversation or login with your twitter credentials to ask questions. User Group Pavilion 2nd Floor, Moscone West 12:30PM-2:00PM UGF5131 - Migrating from Oracle Enterprise Manager 10g Grid Control to 12c Cloud Control    Leighton Nelson - Database Administrator, Mercy Moscone West - 2011 2:15PM-3:15PM UGF6511 -  Database Performance Tuning: Get the Best out of Oracle Enterprise Manager 12c Cloud Control Mike Ault - Oracle Guru, TEXAS MEMORY SYSTEMS INC Tariq Farooq - CEO/Founder, BrainSurface Moscone West - 2011 3:30PM-4:30PM UGF4556 - Will It Blend? Verifying Capacity in Server and Database Consolidations Jeremiah Wilton - Database Technology, Blue Gecko / DatAvail Moscone West - 2018 3:30PM-4:30PM UGF10400 - Oracle Enterprise Manager 12c: Monitoring, Metric Extensions, and Configuration Best Practices Kellyn Pot'Vin - Sr. Technical Consultant, Enkitec Moscone West - 2011 Stay Connected: Twitter |  Face book |  You Tube |  Linked in |  Newsletter

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• To ref or not to ref

  - by nmarun

  So the question is what is the point of passing a reference type along with the ref keyword? I have an Employee class as below: 1: public class Employee 2: { 3: public string FirstName { get; set; } 4: public string LastName { get; set; } 5:  6: public override string ToString() 7: { 8: return string.Format("{0}-{1}", FirstName, LastName); 9: } 10: } In my calling class, I say: 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(Employee employee) 16: { 17: employee.FirstName = "Smith"; 18: employee.LastName = "Doe"; 19: } 20: }   After having a look at the code, you’ll probably say, Well, an instance of a class gets passed as a reference, so any changes to the instance inside the CallSomeMethod, actually modifies the original object. Hence the output will be ‘John-Doe’ on the first call and ‘Smith-Doe’ on the second. And you’re right: So the question is what’s the use of passing this Employee parameter as a ref? 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(ref employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(ref Employee employee) 16: { 17: employee.FirstName = "Smith"; 18: employee.LastName = "Doe"; 19: } 20: } The output is still the same: Ok, so is there really a need to pass a reference type using the ref keyword? I’ll remove the ‘ref’ keyword and make one more change to the CallSomeMethod method. 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(Employee employee) 16: { 17: employee = new Employee 18: { 19: FirstName = "Smith", 20: LastName = "John" 21: }; 22: } 23: } In line 17 you’ll see I’ve ‘new’d up the incoming Employee parameter and then set its properties to new values. The output tells me that the original instance of the Employee class does not change. Huh? But an instance of a class gets passed by reference, so why did the values not change on the original instance or how do I keep the two instances in-sync all the times? Aah, now here’s the answer. In order to keep the objects in sync, you pass them using the ‘ref’ keyword. 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(ref employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(ref Employee employee) 16: { 17: employee = new Employee 18: { 19: FirstName = "Smith", 20: LastName = "John" 21: }; 22: } 23: } Viola! Now, to prove it beyond doubt, I said, let me try with another reference type: string. 1: class Program 2: { 3: static void Main() 4: { 5: string name = "abc"; 6: Console.WriteLine(name); 7: CallSomeMethod(ref name); 8: Console.WriteLine(name); 9: } 10:  11: private static void CallSomeMethod(ref string name) 12: { 13: name = "def"; 14: } 15: } The output was as expected, first ‘abc’ and then ‘def’ - proves the 'ref' keyword works here as well. Now, what if I remove the ‘ref’ keyword? The output should still be the same as the above right, since string is a reference type? 1: class Program 2: { 3: static void Main() 4: { 5: string name = "abc"; 6: Console.WriteLine(name); 7: CallSomeMethod(name); 8: Console.WriteLine(name); 9: } 10:  11: private static void CallSomeMethod(string name) 12: { 13: name = "def"; 14: } 15: } Wrong, the output shows ‘abc’ printed twice. Wait a minute… now how could this be? This is because string is an immutable type. This means that any time you modify an instance of string, new memory address is allocated to the instance. The effect is similar to ‘new’ing up the Employee instance inside the CallSomeMethod in the absence of the ‘ref’ keyword. Verdict: ref key came to the rescue and saved the planet… again!

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• Unique Business Value vs. Unique IT

  - by barry.perkins

  When the age of computing started, technology was new, exciting, full of potential and had a long way to grow. Vendor architectures were proprietary, and limited in function at first, growing in capability and complexity over time. There were few if any "standards", let alone "open standards" and the concepts of "open systems", and "open architectures" were far in the future. Companies employed intelligent, talented and creative people to implement the best possible solutions for their company. At first, those solutions were "unique" to each company. As time progressed, standards emerged, companies shared knowledge, business capability supplied by technology grew, and companies continued to expand their use of technology. Taking advantage of change required companies to struggle through periodic "revolutionary" change cycles, struggling through costly changes that were fraught with risk, resulted in solutions with an increasingly shorter half-life, and frequently required altering existing business processes and retraining employees and partner businesses. The pace of technological invention and implementation grew at an ever increasing rate, making the "revolutionary" approach based upon "proprietary" or "closed" architectures or technologies no longer viable. Concurrent with the advancement of technology, the rate of change in business increased, leading us to the incredibly fast paced, highly charged, and competitive global economy that we have today, where the most successful companies are companies that are good at implementing, leveraging and exploiting change. Fast forward to today, a world where dramatic changes in business and technology happen continually, a world where "evolutionary" change is crucial. Companies can no longer afford to build "unique IT", nor can they afford regular intervals of "revolutionary" change, with the associated costs and risks. Human ingenuity was once again up to the task, turning technology into a platform supporting business through evolutionary change, by employing "open": open standards; open systems; open architectures; and open solutions. Employing "open", enables companies to implement systems based upon technology, capability and standards that will evolve over time, providing a solid platform upon which a company can drive business needs, requirements, functions, and processes down into the technology, rather than exposing technology to the business, allowing companies to focus on providing "unique business value" rather than "unique IT". The big question! Does moving from "older" technology that no longer meets the needs of today's business, to new "open" technology require yet another "revolutionary change"? A "revolutionary" change with a short half-life, camouflaging reality with great marketing? The answer is "perhaps". With the endless options available to choose from, it is entirely possible to implement a solution that may work well today, but in 5 years time will become yet another albatross for the company to bear. Some solutions may look good today, solving a budget challenge by reducing cost, or solving a specific tactical challenge, but result in highly complex environments, that may be difficult to manage and maintain and limit the future potential of your business. Put differently, some solutions might push today's challenge into the future, resulting in a more complex and expensive solution. There is no such thing as a "1 size fits all" IT solution for business. If all companies implemented business solutions based upon technology that required, or forced the same business processes across all businesses in an industry, it would be extremely difficult to show competitive advantage through "unique business value". It would be equally difficult to "evolve" to meet or exceed business needs and keep up with today's rapid pace of change. How does one ensure that they do not jump from one trap directly into another? Or to put it positively, there are solutions available today that can address these challenges and issues. How does one ensure that the buying decision of today will serve the business well for years into the future? Intelligent & Informed decisions - "buying right" In a previous blog entry, we discussed the value of linking tactical to strategic The key is driving the focus to what is best for your business, handling today's tactical issues while also aligning with a roadmap/strategy that is tightly aligned with your strategic business objectives. When considering the plethora of possible options that provide various approaches to solving today's complex business problems, it is extremely important to ensure that vendors supplying those options, focus on what is best for your business, supplying sufficient information, providing adequate answers to questions, addressing challenges, issues, concerns and objections honestly and openly, and focus on supplying solutions that are tailored for, and deliver the most business value possible for your business. Here are a few questions to consider relative to the proposed options that should help ensure that today's solution doesn't become tomorrow's problem. Do the proposed solutions: Solve the problem(s) you are trying to address? Provide a solid foundation upon which to grow/enhance your business? Provide tactical gains that align with and enable your strategic business goals/objectives? Provide an infrastructure that can be leveraged with subsequent projects? Solve problems for the business overall, the lines of business, or just IT? Simplify your current environment Provide the basis for business: Efficiency Agility Clarity governance, risk, compliance real time business visibility and trend analysis Does your IT staff have the knowledge/experience to successfully manage the proposed systems once they are deployed in production? Done well, you will be presented with options tailored to your business, that enable you to drive the "unique business value" necessary to help your business stand out from others, creating a distinct competitive advantage, delivering what your customers need, when they need it, so you can attract new customers, new business, and grow top line revenue, all at a cost that provides a strong Return on Investment/Return on Assets. The net result is growth with managed cost providing significantly improved profit margin and shareholder value.

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• Partition Wise Joins

  - by jean-pierre.dijcks

  Some say they are the holy grail of parallel computing and PWJ is the basis for a shared nothing system and the only join method that is available on a shared nothing system (yes this is oversimplified!). The magic in Oracle is of course that is one of many ways to join data. And yes, this is the old flexibility vs. simplicity discussion all over, so I won't go there... the point is that what you must do in a shared nothing system, you can do in Oracle with the same speed and methods. The Theory A partition wise join is a join between (for simplicity) two tables that are partitioned on the same column with the same partitioning scheme. In shared nothing this is effectively hard partitioning locating data on a specific node / storage combo. In Oracle is is logical partitioning. If you now join the two tables on that partitioned column you can break up the join in smaller joins exactly along the partitions in the data. Since they are partitioned (grouped) into the same buckets, all values required to do the join live in the equivalent bucket on either sides. No need to talk to anyone else, no need to redistribute data to anyone else... in short, the optimal join method for parallel processing of two large data sets. PWJ's in Oracle Since we do not hard partition the data across nodes in Oracle we use the Partitioning option to the database to create the buckets, then set the Degree of Parallelism (or run Auto DOP - see here) and get our PWJs. The main questions always asked are: How many partitions should I create? What should my DOP be? In a shared nothing system the answer is of course, as many partitions as there are nodes which will be your DOP. In Oracle we do want you to look at the workload and concurrency, and once you know that to understand the following rules of thumb. Within Oracle we have more ways of joining of data, so it is important to understand some of the PWJ ideas and what it means if you have an uneven distribution across processes. Assume we have a simple scenario where we partition the data on a hash key resulting in 4 hash partitions (H1 -H4). We have 2 parallel processes that have been tasked with reading these partitions (P1 - P2). The work is evenly divided assuming the partitions are the same size and we can scan this in time t1 as shown below. Now assume that we have changed the system and have a 5th partition but still have our 2 workers P1 and P2. The time it takes is actually 50% more assuming the 5th partition has the same size as the original H1 - H4 partitions. In other words to scan these 5 partitions, the time t2 it takes is not 1/5th more expensive, it is a lot more expensive and some other join plans may now start to look exciting to the optimizer. Just to post the disclaimer, it is not as simple as I state it here, but you get the idea on how much more expensive this plan may now look... Based on this little example there are a few rules of thumb to follow to get the partition wise joins. First, choose a DOP that is a factor of two (2). So always choose something like 2, 4, 8, 16, 32 and so on... Second, choose a number of partitions that is larger or equal to 2* DOP. Third, make sure the number of partitions is divisible through 2 without orphans. This is also known as an even number... Fourth, choose a stable partition count strategy, which is typically hash, which can be a sub partitioning strategy rather than the main strategy (range - hash is a popular one). Fifth, make sure you do this on the join key between the two large tables you want to join (and this should be the obvious one...). Translating this into an example: DOP = 8 (determined based on concurrency or by using Auto DOP with a cap due to concurrency) says that the number of partitions >= 16. Number of hash (sub) partitions = 32, which gives each process four partitions to work on. This number is somewhat arbitrary and depends on your data and system. In this case my main reasoning is that if you get more room on the box you can easily move the DOP for the query to 16 without repartitioning... and of course it makes for no leftovers on the table... And yes, we recommend up-to-date statistics. And before you start complaining, do read this post on a cool way to do stats in 11.

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