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  • Joins in single-table queries

    - by Rob Farley
    Tables are only metadata. They don’t store data. I’ve written something about this before, but I want to take a viewpoint of this idea around the topic of joins, especially since it’s the topic for T-SQL Tuesday this month. Hosted this time by Sebastian Meine (@sqlity), who has a whole series on joins this month. Good for him – it’s a great topic. In that last post I discussed the fact that we write queries against tables, but that the engine turns it into a plan against indexes. My point wasn’t simply that a table is actually just a Clustered Index (or heap, which I consider just a special type of index), but that data access always happens against indexes – never tables – and we should be thinking about the indexes (specifically the non-clustered ones) when we write our queries. I described the scenario of looking up phone numbers, and how it never really occurs to us that there is a master list of phone numbers, because we think in terms of the useful non-clustered indexes that the phone companies provide us, but anyway – that’s not the point of this post. So a table is metadata. It stores information about the names of columns and their data types. Nullability, default values, constraints, triggers – these are all things that define the table, but the data isn’t stored in the table. The data that a table describes is stored in a heap or clustered index, but it goes further than this. All the useful data is going to live in non-clustered indexes. Remember this. It’s important. Stop thinking about tables, and start thinking about indexes. So let’s think about tables as indexes. This applies even in a world created by someone else, who doesn’t have the best indexes in mind for you. I’m sure you don’t need me to explain Covering Index bit – the fact that if you don’t have sufficient columns “included” in your index, your query plan will either have to do a Lookup, or else it’ll give up using your index and use one that does have everything it needs (even if that means scanning it). If you haven’t seen that before, drop me a line and I’ll run through it with you. Or go and read a post I did a long while ago about the maths involved in that decision. So – what I’m going to tell you is that a Lookup is a join. When I run SELECT CustomerID FROM Sales.SalesOrderHeader WHERE SalesPersonID = 285; against the AdventureWorks2012 get the following plan: I’m sure you can see the join. Don’t look in the query, it’s not there. But you should be able to see the join in the plan. It’s an Inner Join, implemented by a Nested Loop. It’s pulling data in from the Index Seek, and joining that to the results of a Key Lookup. It clearly is – the QO wouldn’t call it that if it wasn’t really one. It behaves exactly like any other Nested Loop (Inner Join) operator, pulling rows from one side and putting a request in from the other. You wouldn’t have a problem accepting it as a join if the query were slightly different, such as SELECT sod.OrderQty FROM Sales.SalesOrderHeader AS soh JOIN Sales.SalesOrderDetail as sod on sod.SalesOrderID = soh.SalesOrderID WHERE soh.SalesPersonID = 285; Amazingly similar, of course. This one is an explicit join, the first example was just as much a join, even thought you didn’t actually ask for one. You need to consider this when you’re thinking about your queries. But it gets more interesting. Consider this query: SELECT SalesOrderID FROM Sales.SalesOrderHeader WHERE SalesPersonID = 276 AND CustomerID = 29522; It doesn’t look like there’s a join here either, but look at the plan. That’s not some Lookup in action – that’s a proper Merge Join. The Query Optimizer has worked out that it can get the data it needs by looking in two separate indexes and then doing a Merge Join on the data that it gets. Both indexes used are ordered by the column that’s indexed (one on SalesPersonID, one on CustomerID), and then by the CIX key SalesOrderID. Just like when you seek in the phone book to Farley, the Farleys you have are ordered by FirstName, these seek operations return the data ordered by the next field. This order is SalesOrderID, even though you didn’t explicitly put that column in the index definition. The result is two datasets that are ordered by SalesOrderID, making them very mergeable. Another example is the simple query SELECT CustomerID FROM Sales.SalesOrderHeader WHERE SalesPersonID = 276; This one prefers a Hash Match to a standard lookup even! This isn’t just ordinary index intersection, this is something else again! Just like before, we could imagine it better with two whole tables, but we shouldn’t try to distinguish between joining two tables and joining two indexes. The Query Optimizer can see (using basic maths) that it’s worth doing these particular operations using these two less-than-ideal indexes (because of course, the best indexese would be on both columns – a composite such as (SalesPersonID, CustomerID – and it would have the SalesOrderID column as part of it as the CIX key still). You need to think like this too. Not in terms of excusing single-column indexes like the ones in AdventureWorks2012, but in terms of having a picture about how you’d like your queries to run. If you start to think about what data you need, where it’s coming from, and how it’s going to be used, then you will almost certainly write better queries. …and yes, this would include when you’re dealing with regular joins across multiples, not just against joins within single table queries.

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  • Puppet: Making Windows Awesome Since 2011

    - by Robz / Fervent Coder
    Originally posted on: http://geekswithblogs.net/robz/archive/2014/08/07/puppet-making-windows-awesome-since-2011.aspxPuppet was one of the first configuration management (CM) tools to support Windows, way back in 2011. It has the heaviest investment on Windows infrastructure with 1/3 of the platform client development staff being Windows folks.  It appears that Microsoft believed an end state configuration tool like Puppet was the way forward, so much so that they cloned Puppet’s DSL (domain-specific language) in many ways and are calling it PowerShell DSC. Puppet Labs is pushing the envelope on Windows. Here are several things to note: Puppet x64 Ruby support for Windows coming in v3.7.0. An awesome ACL module (with order, SIDs and very granular control of permissions it is best of any CM). A wealth of modules that work with Windows on the Forge (and more on GitHub). Documentation solely for Windows folks - https://docs.puppetlabs.com/windows. Some of the common learning points with Puppet on Windows user are noted in this recent blog post. Microsoft OpenTech supports Puppet. Azure has the ability to deploy a Puppet Master (http://puppetlabs.com/solutions/microsoft). At Microsoft //Build 2014 in the Day 2 Keynote Puppet Labs CEO Luke Kanies co-presented with Mark Russonivich (http://channel9.msdn.com/Events/Build/2014/KEY02  fast forward to 19:30)! Puppet has a Visual Studio Plugin! It can be overwhelming learning a new tool like Puppet at first, but Puppet Labs has some resources to help you on that path. Take a look at the Learning VM, which has a quest-based learning tool. For real-time questions, feel free to drop onto #puppet on freenode.net (yes, some folks still use IRC) with questions, and #puppet-dev with thoughts/feedback on the language itself. You can subscribe to puppet-users / puppet-dev mailing lists. There is also ask.puppetlabs.com for questions and Server Fault if you want to go to a Stack Exchange site. There are books written on learning Puppet. There are even Puppet User Groups (PUGs) and other community resources! Puppet does take some time to learn, but with anything you need to learn, you need to weigh the benefits versus the ramp up time. I learned NHibernate once, it had a very high ramp time back then but was the only game on the street. Puppet’s ramp up time is considerably less than that. The advantage is that you are learning a DSL, and it can apply to multiple platforms (Linux, Windows, OS X, etc.) with the same Puppet resource constructs. As you learn Puppet you may wonder why it has a DSL instead of just leveraging the language of Ruby (or maybe this is one of those things that keeps you up wondering at night). I like the DSL over a small layer on top of Ruby. It allows the Puppet language to be portable and go more places. It makes you think about the end state of what you want to achieve in a declarative sense instead of in an imperative sense. You may also find that right now Puppet doesn’t run manifests (scripts) in order of the way resources are specified. This is the number one learning point for most folks. As a long time consternation of some folks about Puppet, manifest ordering was not possible in the past. In fact it might be why some other CMs exist! As of 3.3.0, Puppet can do manifest ordering, and it will be the default in Puppet 4. http://puppetlabs.com/blog/introducing-manifest-ordered-resources You may have caught earlier that I mentioned PowerShell DSC. But what about DSC? Shouldn’t that be what Windows users want to choose? Other CMs are integrating with DSC, will Puppet follow suit and integrate with DSC? The biggest concern that I have with DSC is it’s lack of visibility in fine-grained reporting of changes (which Puppet has). The other is that it is a very young Microsoft product (pre version 3, you know what they say :) ). I tried getting it working in December and ran into some issues. I’m hoping that newer releases are there that actually work, it does have some promising capabilities, it just doesn’t quite come up to the standard of something that should be used in production. In contrast Puppet is almost a ten year old language with an active community! It’s very stable, and when trusting your business to configuration management, you want something that has been around awhile and has been proven. Give DSC another couple of releases and you might see more folks integrating with it. That said there may be a future with DSC integration. Portability and fine-grained reporting of configuration changes are reasons to take a closer look at Puppet on Windows. Yes, Puppet on Windows is here to stay and it’s continually getting better folks.

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  • Optimizing AES modes on Solaris for Intel Westmere

    - by danx
    Optimizing AES modes on Solaris for Intel Westmere Review AES is a strong method of symmetric (secret-key) encryption. It is a U.S. FIPS-approved cryptographic algorithm (FIPS 197) that operates on 16-byte blocks. AES has been available since 2001 and is widely used. However, AES by itself has a weakness. AES encryption isn't usually used by itself because identical blocks of plaintext are always encrypted into identical blocks of ciphertext. This encryption can be easily attacked with "dictionaries" of common blocks of text and allows one to more-easily discern the content of the unknown cryptotext. This mode of encryption is called "Electronic Code Book" (ECB), because one in theory can keep a "code book" of all known cryptotext and plaintext results to cipher and decipher AES. In practice, a complete "code book" is not practical, even in electronic form, but large dictionaries of common plaintext blocks is still possible. Here's a diagram of encrypting input data using AES ECB mode: Block 1 Block 2 PlainTextInput PlainTextInput | | | | \/ \/ AESKey-->(AES Encryption) AESKey-->(AES Encryption) | | | | \/ \/ CipherTextOutput CipherTextOutput Block 1 Block 2 What's the solution to the same cleartext input producing the same ciphertext output? The solution is to further process the encrypted or decrypted text in such a way that the same text produces different output. This usually involves an Initialization Vector (IV) and XORing the decrypted or encrypted text. As an example, I'll illustrate CBC mode encryption: Block 1 Block 2 PlainTextInput PlainTextInput | | | | \/ \/ IV >----->(XOR) +------------->(XOR) +---> . . . . | | | | | | | | \/ | \/ | AESKey-->(AES Encryption) | AESKey-->(AES Encryption) | | | | | | | | | \/ | \/ | CipherTextOutput ------+ CipherTextOutput -------+ Block 1 Block 2 The steps for CBC encryption are: Start with a 16-byte Initialization Vector (IV), choosen randomly. XOR the IV with the first block of input plaintext Encrypt the result with AES using a user-provided key. The result is the first 16-bytes of output cryptotext. Use the cryptotext (instead of the IV) of the previous block to XOR with the next input block of plaintext Another mode besides CBC is Counter Mode (CTR). As with CBC mode, it also starts with a 16-byte IV. However, for subsequent blocks, the IV is just incremented by one. Also, the IV ix XORed with the AES encryption result (not the plain text input). Here's an illustration: Block 1 Block 2 PlainTextInput PlainTextInput | | | | \/ \/ AESKey-->(AES Encryption) AESKey-->(AES Encryption) | | | | \/ \/ IV >----->(XOR) IV + 1 >---->(XOR) IV + 2 ---> . . . . | | | | \/ \/ CipherTextOutput CipherTextOutput Block 1 Block 2 Optimization Which of these modes can be parallelized? ECB encryption/decryption can be parallelized because it does more than plain AES encryption and decryption, as mentioned above. CBC encryption can't be parallelized because it depends on the output of the previous block. However, CBC decryption can be parallelized because all the encrypted blocks are known at the beginning. CTR encryption and decryption can be parallelized because the input to each block is known--it's just the IV incremented by one for each subsequent block. So, in summary, for ECB, CBC, and CTR modes, encryption and decryption can be parallelized with the exception of CBC encryption. How do we parallelize encryption? By interleaving. Usually when reading and writing data there are pipeline "stalls" (idle processor cycles) that result from waiting for memory to be loaded or stored to or from CPU registers. Since the software is written to encrypt/decrypt the next data block where pipeline stalls usually occurs, we can avoid stalls and crypt with fewer cycles. This software processes 4 blocks at a time, which ensures virtually no waiting ("stalling") for reading or writing data in memory. Other Optimizations Besides interleaving, other optimizations performed are Loading the entire key schedule into the 128-bit %xmm registers. This is done once for per 4-block of data (since 4 blocks of data is processed, when present). The following is loaded: the entire "key schedule" (user input key preprocessed for encryption and decryption). This takes 11, 13, or 15 registers, for AES-128, AES-192, and AES-256, respectively The input data is loaded into another %xmm register The same register contains the output result after encrypting/decrypting Using SSSE 4 instructions (AESNI). Besides the aesenc, aesenclast, aesdec, aesdeclast, aeskeygenassist, and aesimc AESNI instructions, Intel has several other instructions that operate on the 128-bit %xmm registers. Some common instructions for encryption are: pxor exclusive or (very useful), movdqu load/store a %xmm register from/to memory, pshufb shuffle bytes for byte swapping, pclmulqdq carry-less multiply for GCM mode Combining AES encryption/decryption with CBC or CTR modes processing. Instead of loading input data twice (once for AES encryption/decryption, and again for modes (CTR or CBC, for example) processing, the input data is loaded once as both AES and modes operations occur at in the same function Performance Everyone likes pretty color charts, so here they are. I ran these on Solaris 11 running on a Piketon Platform system with a 4-core Intel Clarkdale processor @3.20GHz. Clarkdale which is part of the Westmere processor architecture family. The "before" case is Solaris 11, unmodified. Keep in mind that the "before" case already has been optimized with hand-coded Intel AESNI assembly. The "after" case has combined AES-NI and mode instructions, interleaved 4 blocks at-a-time. « For the first table, lower is better (milliseconds). The first table shows the performance improvement using the Solaris encrypt(1) and decrypt(1) CLI commands. I encrypted and decrypted a 1/2 GByte file on /tmp (swap tmpfs). Encryption improved by about 40% and decryption improved by about 80%. AES-128 is slighty faster than AES-256, as expected. The second table shows more detail timings for CBC, CTR, and ECB modes for the 3 AES key sizes and different data lengths. » The results shown are the percentage improvement as shown by an internal PKCS#11 microbenchmark. And keep in mind the previous baseline code already had optimized AESNI assembly! The keysize (AES-128, 192, or 256) makes little difference in relative percentage improvement (although, of course, AES-128 is faster than AES-256). Larger data sizes show better improvement than 128-byte data. Availability This software is in Solaris 11 FCS. It is available in the 64-bit libcrypto library and the "aes" Solaris kernel module. You must be running hardware that supports AESNI (for example, Intel Westmere and Sandy Bridge, microprocessor architectures). The easiest way to determine if AES-NI is available is with the isainfo(1) command. For example, $ isainfo -v 64-bit amd64 applications pclmulqdq aes sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov amd_sysc cx8 tsc fpu 32-bit i386 applications pclmulqdq aes sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov sep cx8 tsc fpu No special configuration or setup is needed to take advantage of this software. Solaris libraries and kernel automatically determine if it's running on AESNI-capable machines and execute the correctly-tuned software for the current microprocessor. Summary Maximum throughput of AES cipher modes can be achieved by combining AES encryption with modes processing, interleaving encryption of 4 blocks at a time, and using Intel's wide 128-bit %xmm registers and instructions. References "Block cipher modes of operation", Wikipedia Good overview of AES modes (ECB, CBC, CTR, etc.) "Advanced Encryption Standard", Wikipedia "Current Modes" describes NIST-approved block cipher modes (ECB,CBC, CFB, OFB, CCM, GCM)

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  • Searching for the Perfect Developer&rsquo;s Laptop.

    - by mbcrump
    I have been in the market for a new computer for several months. I set out with a budget of around $1200. I knew up front that the machine would be used for developing applications and maybe some light gaming. I kept switching between buying a laptop or a desktop but the laptop won because: With a Laptop, I can carry it everywhere and with a desktop I can’t. I searched for about 2 weeks and narrowed it down to a list of must-have’s : i7 Processor (I wasn’t going to settle for an i5 or AMD. I wanted a true Quad-core machine, not 2 dual-core fused together). 15.6” monitor SSD 128GB or Larger. – It’s almost 2011 and I don’t want an old standard HDD in this machine. 8GB of DDR3 Ram. – The more the better, right? 1GB Video Card (Prefer NVidia) – I might want to play games with this. HDMI Port – Almost a standard on new Machines. This would be used when I am on the road and want to stream Netflix to the HDTV in the Hotel room. Webcam Built-in – This would be to video chat with the wife and kids if I am on the road. 6-Cell Battery. – I’ve read that an i7 in a laptop really kills the battery. A 6-cell or 9-cell is even better. That is a pretty long list for a budget of around $1200. I searched around the internet and could not buy this machine prebuilt for under $1200. That was even with coupons and my company’s 10% Dell discount. The only way that I would get a machine like this was to buy a prebuilt and replace parts. I chose the  Lenovo Y560 on Newegg to start as my base. Below is a top-down picture of it.   Part 1: The Hardware The Specs for this machine: Color :  GrayOperating System : Windows 7 Home Premium 64-bitCPU Type : Intel Core i7-740QM(1.73GHz)Screen : 15.6" WXGAMemory Size : 4GB DDR3Hard Disk : 500GBOptical Drive : DVD±R/RWGraphics Card : ATI Mobility Radeon HD 5730Video Memory : 1GBCommunication : Gigabit LAN and WLANCard slot : 1 x Express Card/34Battery Life : Up to 3.5 hoursDimensions : 15.20" x 10.00" x 0.80" - 1.30"Weight : 5.95 lbs. This computer met most of the requirements above except that it didn’t come with an SSD or have 8GB of DDR3 Memory. So, I needed to start shopping except this time for an SSD. I asked around on twitter and other hardware forums and everyone pointed me to the Crucial C300 SSD. After checking prices of the drive, it was going to cost an extra $275 bucks and I was going from a spacious 500GB drive to 128GB. After watching some of the SSD videos on YouTube I started feeling better. Below is a pic of the Crucial C300 SSD. The second thing that I needed to upgrade was the RAM. It came with 4GB of DDR3 RAM, but it was slow. I decided to buy the Crucial 8GB (4GB x 2) Kit from Newegg. This RAM cost an extra $120 and had a CAS Latency of 7. In the end this machine delivered everything that I wanted and it cost around $1300. You are probably saying, well your budget was $1200. I have spare parts that I’m planning on selling on eBay or Anandtech.  =) If you are interested then shoot me an email and I will give you a great deal mbcrump[at]gmail[dot]com. 500GB Laptop 7200RPM HDD 4GB of DDR3 RAM (2GB x 2) faceVision HD 720p Camera – Unopened In the end my Windows Experience Rating of the SSD was 7.7 and the CPU 7.1. The max that you can get is a 7.9. Part 2: The Software I’m very lucky that I get a lot of software for free. When choosing a laptop, the OS really doesn’t matter because I would never keep the bloatware pre-installed or Windows 7 Home Premium on my main development machine. Matter of fact, as soon as I got the laptop, I immediately took out the old HDD without booting into it. After I got the SSD into the machine, I installed Windows 7 Ultimate 64-Bit. The BIOS was out of date, so I updated that to the latest version and started downloading drivers off of Lenovo’s site. I had to download the Wireless Networking Drivers to a USB-Key before I could get my machine on my wireless network. I also discovered that if the date on your computer is off then you cannot join the Windows 7 Homegroup until you fix it. I’m aware that most people like peeking into what programs other software developers use and I went ahead and listed my “essentials” of a fresh build. I am a big Silverlight guy, so naturally some of the software listed below is specific to Silverlight. You should also check out my master list of Tools and Utilities for the .NET Developer. See a killer app that I’m missing? Feel free to leave it in the comments below. My Software Essential List. CPU-Z Dropbox Everything Search Tool Expression Encoder Update Expression Studio 4 Ultimate Foxit Reader Google Chrome Infragistics NetAdvantage Ultimate Edition Keepass Microsoft Office Professional Plus 2010 Microsoft Security Essentials 2  Mindscape Silverlight Elements Notepad 2 (with shell extension) Precode Code Snippet Manager RealVNC Reflector ReSharper v5.1.1753.4 Silverlight 4 Toolkit Silverlight Spy Snagit 10 SyncFusion Reporting Controls for Silverlight Telerik Silverlight RadControls TweetDeck Virtual Clone Drive Visual Studio 2010 Feature Pack 2 Visual Studio 2010 Ultimate VS KB2403277 Update to get Feature Pack 2 to work. Windows 7 Ultimate 64-Bit Windows Live Essentials 2011 Windows Live Writer Backup. Windows Phone Development Tools That is pretty much it, I have a new laptop and am happy with the purchase. If you have any questions then feel free to leave a comment below.  Subscribe to my feed

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  • SQL SERVER – Weekly Series – Memory Lane – #032

    - by Pinal Dave
    Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Complete Series of Database Coding Standards and Guidelines SQL SERVER Database Coding Standards and Guidelines – Introduction SQL SERVER – Database Coding Standards and Guidelines – Part 1 SQL SERVER – Database Coding Standards and Guidelines – Part 2 SQL SERVER Database Coding Standards and Guidelines Complete List Download Explanation and Example – SELF JOIN When all of the data you require is contained within a single table, but data needed to extract is related to each other in the table itself. Examples of this type of data relate to Employee information, where the table may have both an Employee’s ID number for each record and also a field that displays the ID number of an Employee’s supervisor or manager. To retrieve the data tables are required to relate/join to itself. Insert Multiple Records Using One Insert Statement – Use of UNION ALL This is very interesting question I have received from new developer. How can I insert multiple values in table using only one insert? Now this is interesting question. When there are multiple records are to be inserted in the table following is the common way using T-SQL. Function to Display Current Week Date and Day – Weekly Calendar Straight blog post with script to find current week date and day based on the parameters passed in the function.  2008 In my beginning years, I have almost same confusion as many of the developer had in their earlier years. Here are two of the interesting question which I have attempted to answer in my early year. Even if you are experienced developer may be you will still like to read following two questions: Order Of Column In Index Order of Conditions in WHERE Clauses Example of DISTINCT in Aggregate Functions Have you ever used DISTINCT with the Aggregation Function? Here is a simple example about how users can do it. Create a Comma Delimited List Using SELECT Clause From Table Column Straight to script example where I explained how to do something easy and quickly. Compound Assignment Operators SQL SERVER 2008 has introduced new concept of Compound Assignment Operators. Compound Assignment Operators are available in many other programming languages for quite some time. Compound Assignment Operators is operator where variables are operated upon and assigned on the same line. PIVOT and UNPIVOT Table Examples Here is a very interesting question – the answer to the question can be YES or NO both. “If we PIVOT any table and UNPIVOT that table do we get our original table?” Read the blog post to get the explanation of the question above. 2009 What is Interim Table – Simple Definition of Interim Table The interim table is a table that is generated by joining two tables and not the final result table. In other words, when two tables are joined they create an interim table as resultset but the resultset is not final yet. It may be possible that more tables are about to join on the interim table, and more operations are still to be applied on that table (e.g. Order By, Having etc). Besides, it may be possible that there is no interim table; sometimes final table is what is generated when the query is run. 2010 Stored Procedure and Transactions If Stored Procedure is transactional then, it should roll back complete transactions when it encounters any errors. Well, that does not happen in this case, which proves that Stored Procedure does not only provide just the transactional feature to a batch of T-SQL. Generate Database Script for SQL Azure When talking about SQL Azure the most common complaint I hear is that the script generated from stand-along SQL Server database is not compatible with SQL Azure. This was true for some time for sure but not any more. If you have SQL Server 2008 R2 installed you can follow the guideline below to generate a script which is compatible with SQL Azure. Convert IN to EXISTS – Performance Talk It is NOT necessary that every time when IN is replaced by EXISTS it gives better performance. However, in our case listed above it does for sure give better performance. You can read about this subject in the associated blog post. Subquery or Join – Various Options – SQL Server Engine Knows the Best Every single time whenever there is a performance tuning exercise, I hear the conversation from developer where some prefer subquery and some prefer join. In this two part blog post, I explain the same in the detail with examples. Part 1 | Part 2 Merge Operations – Insert, Update, Delete in Single Execution MERGE is a new feature that provides an efficient way to do multiple DML operations. In earlier versions of SQL Server, we had to write separate statements to INSERT, UPDATE, or DELETE data based on certain conditions; however, at present, by using the MERGE statement, we can include the logic of such data changes in one statement that even checks when the data is matched and then just update it, and similarly, when the data is unmatched, it is inserted. 2011 Puzzle – Statistics are not updated but are Created Once Here is the quick scenario about my setup. Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated – WHY? Question to You – When to use Function and When to use Stored Procedure Personally, I believe that they are both different things - they cannot be compared. I can say, it will be like comparing apples and oranges. Each has its own unique use. However, they can be used interchangeably at many times and in real life (i.e., production environment). I have personally seen both of these being used interchangeably many times. This is the precise reason for asking this question. 2012 In year 2012 I had two interesting series ran on the blog. If there is no fun in learning, the learning becomes a burden. For the same reason, I had decided to build a three part quiz around SEQUENCE. The quiz was to identify the next value of the sequence. I encourage all of you to take part in this fun quiz. Guess the Next Value – Puzzle 1 Guess the Next Value – Puzzle 2 Guess the Next Value – Puzzle 3 Guess the Next Value – Puzzle 4 Simple Example to Configure Resource Governor – Introduction to Resource Governor Resource Governor is a feature which can manage SQL Server Workload and System Resource Consumption. We can limit the amount of CPU and memory consumption by limiting /governing /throttling on the SQL Server. If there are different workloads running on SQL Server and each of the workload needs different resources or when workloads are competing for resources with each other and affecting the performance of the whole server resource governor is a very important task. Tricks to Replace SELECT * with Column Names – SQL in Sixty Seconds #017 – Video  Retrieves unnecessary columns and increases network traffic When a new columns are added views needs to be refreshed manually Leads to usage of sub-optimal execution plan Uses clustered index in most of the cases instead of using optimal index It is difficult to debug SQL SERVER – Load Generator – Free Tool From CodePlex The best part of this SQL Server Load Generator is that users can run multiple simultaneous queries again SQL Server using different login account and different application name. The interface of the tool is extremely easy to use and very intuitive as well. A Puzzle – Swap Value of Column Without Case Statement Let us assume there is a single column in the table called Gender. The challenge is to write a single update statement which will flip or swap the value in the column. For example if the value in the gender column is ‘male’ swap it with ‘female’ and if the value is ‘female’ swap it with ‘male’. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Execute TSQL statement with ExecuteStoreQuery in entity framework 4.0

    - by Jalpesh P. Vadgama
    I was playing with entity framework in recent days and I was searching something that how we can execute TSQL statement in entity framework. And I have found one great way to do that with entity framework ‘ExecuteStoreQuery’ method. It’s executes a TSQL statement against data source given enity framework context and returns strongly typed result. You can find more information about ExcuteStoreQuery from following link. http://msdn.microsoft.com/en-us/library/dd487208.aspx So let’s examine how it works. So Let’s first create a table against which we are going to execute TSQL statement. So I have added a SQL Express database as following. Now once we are done with adding a database let’s add a table called Client like following. Here you can see above Client table is very simple. There are only two fields ClientId and ClientName where ClientId is primary key and ClientName is field where we are going to store client name. Now it’s time to add some data to the table. So I have added some test data like following. Now it’s time to add entity framework model class. So right click project->Add new item and select ADO.NET entity model as following. After clicking on add button a wizard will start it will ask whether we need to create model classes from database or not but we already have our client table ready so I have selected generate from database as following. Once you process further in wizard it will be presented a screen where we can select the our table like following. Now once you click finish it will create model classes with for us. Now we need a gridview control where we need to display those data. So in Default.aspx page I have added a grid control like following. <%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="EntityFramework._Default" %> <asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent"> </asp:Content> <asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent"> <h2> Welcome to ASP.NET! </h2> <p> To learn more about ASP.NET visit <a href="http://www.asp.net" title="ASP.NET Website">www.asp.net</a>. </p> <p> You can also find <a href="http://go.microsoft.com/fwlink/?LinkID=152368&amp;clcid=0x409" title="MSDN ASP.NET Docs">documentation on ASP.NET at MSDN</a>. <asp:GridView ID="grdClient" runat="server"> </asp:GridView> </p> </asp:Content> Now once we are done with adding Gridview its time to write code for server side. So I have written following code in Page_load event of default.aspx page. protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { using (var context = new EntityFramework.TestEntities()) { ObjectResult<Client> result = context.ExecuteStoreQuery<Client>("Select * from Client"); grdClient.DataSource = result; grdClient.DataBind(); } } } Here in the above code you can see that I have written create a object of our entity model and then with the help of the ExecuteStoreQuery method I have execute a simple select TSQL statement which will return a object result. I have bind that object result with gridview to display data. So now we are done with coding.So let’s run application in browser. Following is output as expected. That’s it. Hope you like it. Stay tuned for more..Till then happy programming.

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  • Parner Webcast - Innovations in Products Program

    - by Richard Lefebvre
    We are pleased to invite you to join the Innovations in Products –webcast. Innovations in Products will present Oracle Applications' Product's new functions and features including sales positioning. The key objectives of these webcasts are to inspire System Integrator's implementation personnel to conduct successful after sales in their Customer projects. Innovations in Products will be presented on the 1st Monday of each quarter after the billable day (4:00 to 5:00 PM CET). The webcast is intended for System Integrator's Implementation Certified Specialists but Innovations in Products is open for other interested Oracle Applications system Integrator's personnel as well. At first, two Oracle representatives will discuss Oracle's contribution to Partners. Then you will see product breakout session followed by Q&A with Oracle Experts. Each session will last for maximum 1 hour. A Q&A document covering all questions and answers will be made available after the webcast. What are the Benefits for partners? Find out how Innovations in Products helps you to improve your after sales Discover new functions and features so you can enrich your Customers's solution Learn more about Oracle Applications products, especially sales positioning Hear crucial questions raised by colleague alike, learn from their interest Engage and present your questions to subject experts Be inspired of the richness of Oracle Application portfolio – for your and your customer’s benefit Note: Should you already be familiar with a specific Product, then choose another one. Doing so you would expand your knowledge of the overall Applications portfolio. Some presentations contain product demonstration, although these presentations are not intended to be extremely detailed technical presentations. Note: At the latter part of this email you have also 17 links into the recent Applications Products presentations and 6 links into the Public Sector Value Proposition presentations that were presented in Innovations in Industries -program. Product breakout sessions: Topics Speaker To Register Fusion Applications Technology and Extensibility: A next-generation platform that adapts to client needs. Matthew Johnson, Sr. Director, SCM Product Development, EMEA CLICK HERE Fusion Applications - Transforming your Back-Office Accounting Function: Changing how people work in back office functions to drive value add Liam Nolan, Director, ERP Product Development, EMEA CLICK HERE Fusion HCM & Talent Overview & Extensibility: A more in-depth look into a personalized HCM solution Synco Jonkeren, Vice-President HCM Product Development & Management, EMEA CLICK HERE Fusion HCM Compensation Planning: Compensate To Compete Rosie Warner, Director, HCM Sales Development CLICK HERE Enterprise PLM for the Product Value Chain: Oracle Enterprise PLM offers Industry specific solutions that cover the Product Value Chain Ulf Köster, Sales Development Leader Enterprise PLM, Oracle Western Europe CLICK HERE Oracle's Asset Management and Maintenance Solution: What you need to know to successfully implement Oracle Asset Management solutions within Oracle Installed Base Philip Carey, Asset Management and Maintenance Solution Specialist CLICK HERE For more details please visit Innovations in Products and other breakout sessions on OPN page. Delivery Format Innovations in Products –program is a series of FREE prerecorded Applications product presentations followed by Q&A. It will be delivered over the Web. Participants have the opportunity to submit questions during the web cast via chat and subject matter experts will provide verbal answers live. Innovations in Products consists of several parallel prerecorded product breakout sessions, each lasting for max. 1 hour. At first, two Oracle representatives will discuss Oracle’s contribution to Partners. Then you’ll see the product breakout sessions followed by Q&A with Oracle Experts. A Q&A document covering all questions and answers will be made available after the webcast. You can also see Innovations in Products afterwards as its content will be available online for the next 6-12 months. The next Innovations in Products web casts will be presented as follows: July 2nd 2012 October 1st 2012 January 14th 2013 April 8th 2013. Note: Depending on local network bandwidth please allow some seconds time the presentations to download. You might want to refresh your screen by pressing F5. Duration Maximum 1 hour For further information please contact me Markku Rouhiainen. Recent Innovations in Products presentations Applications Products presented on April the 2nd, 2012 Speaker To Register Fusion CRM: Effective, Efficient and Easy James Penfold , Senior Director, Applications Product Development and Product Management CLICK HERE Fusion HCM: Talent management overview performance, goals, talent review Jaime Losantos Viñolas, Director, HCM Sales Development CLICK HERE Distributed Order Management - Fusion SCM Solution Vikram K Singla, Business Development Director, Supply Chain Management Applications, UK CLICK HERE Oracle Transportation Management Dominic Regan, Senior Director Oracle Transportation Management EMEA CLICK HERE Oracle Value Chain Planning: Demantra Sales & Operation Planning and Demantra Demand Management Lionel Albert, Senior Director Value Chain Planning, EMEA CLICK HERE Oracle CX (Customer Experience) - formerly CEM: Powering Great Customer Experiences Maria Ramirez , CRM Presales Consultant, EPC CLICK HERE EPM 11.1.2.2 Overview Nicholas Cox , EMEA Sales Development Director - Enterprise Performance Management CLICK HERE Oracle Hyperion Profitability and Cost Management, 11.1.2.1 Daniela Lazar , Senior EPM Sales Consultant, EPC CLICK HERE January the 16th 2012 Speaker To Register CRM / ATG: Best-in-Class CRM & Commerce Maria Ramirez , Associate CRM Presales Consultant, EPC CLICK HERE CRM / Automate Business Rules for Maximum Efficiency with OPA (Oracle Policy Automation) Marco Nilo, Associate CRM Presales Consultant, EPC CLICK HERE CRM / InQuira Toby Baker, Principal Sales Consultant, CRM Product Specialist Team CLICK HERE EPM / Business Intelligence Foundation Suite – Sales and Product Updates Liviu Nitescu, Senior BI Sales Consultant, EPC CLICK HERE EPM / Hyperion Planning 11.1.2.1 - Sales & Product Updates Andreea Voinea, EPM Sales Consultant, EPC CLICK HERE ERP / JDE EnterpriseOne Fulfillment Management Overview Mirela Andreea Nasta , ERP Presales Consultant, EPC CLICK HERE ERP / Spotlights on iExpenses Elena Nita ,ERP Presales Consultant, EPC CLICK HERE MDM / Master Data Management Martin Boyd , Senior Director Product Strategy CLICK HERE Product break through session Fusion Applications Human Capital Management Rosie Warner , Director, HCM Sales Development CLICK HERE Recent Innovations in Industries Value Proposition presentations January the 16th 2012 Speaker To Register Process Modernisation Iemke Idsingh Public Sector Solutions Director CLICK HERE Shared Services Ann Smith Business Development Director, Shared Services CLICK HERE Strengthening Financial Discipline Whilst Delivering Cashable Savings Philippa Headley UK Sales Development Director Public Sector - EPM Solutions CLICK HERE Social Welfare Industry Solutions Christian Wernberg-Tougaard Industry Director - Social Welfare CLICK HERE Police Industry Solutions Jeff Penrose Solution Sales Director CLICK HERE Tax and Revenue Management Industry Solutions Andre van der Post Global Director - Tax Solutions and Strategy CLICK HERE  

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  • Advanced Continuous Delivery to Azure from TFS, Part 1: Good Enough Is Not Great

    - by jasont
    The folks over on the TFS / Visual Studio team have been working hard at releasing a steady stream of new features for their new hosted Team Foundation Service in the cloud. One of the most significant features released was simple continuous delivery of your solution into your Azure deployments. The original announcement from Brian Harry can be found here. Team Foundation Service is a great platform for .Net developers who are used to working with TFS on-premises. I’ve been using it since it became available at the //BUILD conference in 2011, and when I recently came to work at Stackify, it was one of the first changes I made. Managing work items is much easier than the tool we were using previously, although there are some limitations (more on that in another blog post). However, when continuous deployment was made available, it blew my mind. It was the killer feature I didn’t know I needed. Not to say that I wasn’t previously an advocate for continuous delivery; just that it was always a pain to set up and configure. Having it hosted - and a one-click setup – well, that’s just the best thing since sliced bread. It made perfect sense: my source code is in the cloud, and my deployment is in the cloud. Great! I can queue up a build from my iPad or phone and just let it go! I quickly tore through the quick setup and saw it all work… sort of. This will be the first in a three part series on how to take the building block of Team Foundation Service continuous delivery and build a CD model that will actually work for any team deploying something more advanced than a “Hello World” example. Part 1: Good Enough Is Not Great Part 2: A Model That Works: Branching and Multiple Deployment Environments Part 3: Other Considerations: SQL, Custom Tasks, Etc Good Enough Is Not Great There. I’ve said it. I certainly hope no one on the TFS team is offended, but it’s the truth. Let’s take a look under the hood and understand how it works, and then why it’s not enough to handle real world CD as-is. How it works. (note that I’ve skipped a couple of steps; I already have my accounts set up and something deployed to Azure) The first step is to establish some oAuth magic between your Azure management portal and your TFS Instance. You do this via the management portal. Once it’s done, you have a new build process template in your TFS instance. (Image lifted from the documentation) From here, you’ll get the usual prompts for security, allowing access, etc. But you’ll also get to pick which Solution in your source control to build. Here’s what the bulk of the build definition looks like. All I’ve had to do is add in the solution to build (notice that mine is from a specific branch – Release – more on that later) and I’ve changed the configuration. I trigger the build, and voila! I have an Azure deployment a few minutes later. The beauty of this is that it’s all in the cloud and I’m not waiting for my machine to compile and upload the package. (I also had to enable the build definition first – by default it is created in disabled state, probably a good thing since it will trigger on every.single.checkin by default.) I get to see a history of deployments from the Azure portal, and can link into TFS to see the associated changesets and work items. You’ll notice also that this build definition also automatically put my code in the Staging slot of my Azure deployment – more on this soon. For now, I can VIP swap and be in production. (P.S. I hate VIP swap and “production” and “staging” in Azure. More on that later too.) That’s it. That’s the default out-of-box experience. Easy, right? But it’s full of room for improvement, so let’s get into that….   The Problems Nothing is perfect (except my code – it’s always perfect), and neither is Continuous Deployment without a bit of work to help it fit your dev team’s process. So what are the issues? Issue 1: Staging vs QA vs Prod vs whatever other environments your team may have. This, for me, is the big hairy one. Remember how this automatically deployed to staging rather than prod for us? There are a couple of issues with this model: If I want to deliver to prod, it requires intervention on my part after deployment (via a VIP swap). If I truly want to promote between environments (i.e. Nightly Build –> Stable QA –> Production) I likely have configuration changes between each environment such as database connection strings and this process (and the VIP swap) doesn’t account for this. Yet. Issue 2: Branching and delivering on every check-in. As I mentioned above, I have set this up to target a specific branch – Release – of my code. For the purposes of this example, I have adopted the “basic” branching strategy as defined by the ALM Rangers. This basically establishes a “Main” trunk where you branch off Dev and Release branches. Granted, the Release branch is usually the only thing you will deploy to production, but you certainly don’t want to roll to production automatically when you merge to the Release branch and check-in (unless you like the thrill of it, and in that case, I like your style, cowboy….). Rather, you have nightly build and QA environments, or if you’ve adopted the feature-branch model you have environments for those. Those are the environments you want to continuously deploy to. But that takes us back to Issue 1: we currently have a 1:1 solution to Azure deployment target. Issue 3: SQL and other custom tasks. Let’s be honest and address the elephant in the room: I need to get some sleep because I see an elephant in the room. But seriously, I can’t think of an application I have touched in the last 10 years that doesn’t need to consider SQL changes when deploying code and upgrading an environment. Microsoft seems perfectly content to ignore this elephant for now: yes, they’ve added Data Tier Applications. But let’s be honest with ourselves again: no one really uses it, and it’s not suitable for anything more complex than a Hello World sample project database. Why? Because it doesn’t fit well into a great source control story. Developers make stored procedure and table changes all day long while coding complex applications, and if someone forgets to go update the DACPAC before the automated deployment, you have a broken build until it’s completed. Developers – not just DBAs – also like to work with SQL in SQL tools, not in Visual Studio. I’m really picking on SQL because that’s generally the biggest concern that I hear. But we need to account for any custom tasks as well in the build process.   The Solutions… ? We’ve taken a look at how this all works, and addressed the shortcomings. In my next post (which I promise will be very, very soon), I will detail how I’ve overcome these shortcomings and used this foundation to create a mature, flexible model for deploying my app – any version, any time, to any environment.

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  • SUPINFO International University in Mauritius

    Since a while I'm considering to pick up my activities as a student and I'd like to get a degree in Computer Science. Personal motivation I mean after all this years as a professional software (and database) developer I have the personal urge to complete this part of my education. Having various certifications by Microsoft and being awarded as an Microsoft Most Valuable Professional (MVP) twice looks pretty awesome on a resume but having a "proper" degree would just complete my package. During the last couple of years I already got in touch with C-SAC (local business school with degree courses), the University of Mauritius and BCS, the Chartered Institute for IT to check the options to enroll as an experienced software developer. Quite frankly, it was kind of alienating to receive that feedback: Start from scratch! No seriously? Spending x amount of years to sit for courses that might be outdated and form part of your daily routine? Probably being in an awkward situation in which your professional expertise might exceed the lecturers knowledge? I don't know... but if that's path to walk... Well, then I might have to go for it. SUPINFO International University Some weeks ago I was contacted by the General Manager, Education Recruitment and Development of Medine Education Village, Yamal Matabudul, to have a chat on how the local IT scene, namely the Mauritius Software Craftsmanship Community (MSCC), could assist in their plans to promote their upcoming campus. Medine went into partnership with the French-based SUPINFO International University and Mauritius will be the 36th location world-wide for SUPINFO. Actually, the concept of SUPINFO is very likely to the common understanding of an apprenticeship in Germany. Not only does a student enroll into the programme but will also be placed into various internships as part of the curriculum. It's a big advantage in my opinion as the person stays in touch with the daily procedures and workflows in the real world of IT. Statements like "We just received a 'crash course' of information and learned new technology which is equivalent to 1.5 months of lectures at the university" wouldn't form part of the experience of such an education. Open Day at the Medine Education Village Last Saturday, Medine organised their Open Day and it was the official inauguration of the SUPINFO campus in Mauritius. It's now listed on their website, too - but be warned, the site is mainly in French language although the courses are all done in English. Not only was it a big opportunity to "hang out" on the campus of Medine but it was great to see the first professional partners for their internship programme, too. Oh, just for the records, IOS Indian Ocean Software Ltd. will also be among the future employers for SUPINFO students. More about that in an upcoming blog entry. Open Day at Medine Education Village - SUPINFO International University in Mauritius Mr Alick Mouriesse, President of SUPINFO, arrived the previous day and he gave all attendees a great overview of the roots of SUPINFO, the general development of the educational syllabus and their high emphasis on their partnerships with local IT companies in order to assist their students to get future jobs but also feel the heartbeat of technology live. Something which is completely missing in classic institutions of tertiary education in Computer Science. And since I was on tour with my children, as usual during weekends, he also talked about the outlook of having a SUPINFO campus in Mauritius. Apart from the close connection to IT companies and providing internships to students, SUPINFO clearly works on an international level. Meaning students of SUPINFO can move around the globe and can continue their studies seamlessly. For example, you might enroll for your first year in France, then continue to do 2nd and 3rd year in Canada or any other country with a SUPINFO campus to earn your bachelor degree, and then live and study in Mauritius for the next 2 years to achieve a Master degree. Having a chat with Dale Smith, Expand Technologies, after his interesting session on Technological Entrepreneurship - TechPreneur More questions by other craftsmen of the Mauritius Software Craftsmanship Community And of course, this concept works in any direction, giving Mauritian students a huge (!) opportunity to live, study and work abroad. And thanks to this, Medine already announced that there will be new facilities near Cascavelle to provide dormitories and other facilities to international students coming to our island. Awesome! Okay, but why SUPINFO? Well, coming back to my original statement - I'd like to get a degree in Computer Science - SUPINFO has a process called Validation of Acquired Experience (VAE) which is tailor-made for employees in the field of IT, and allows you to enroll in their course programme. I already got in touch with their online support chat but was only redirected to some FAQs on their website, unfortunately. So, during the Open Day I seized the opportunity to have an one-on-one conversation with Alick Mouriesse, and he clearly encouraged me to gather my certifications and working experience. SUPINFO does an individual evaluation prior to their assignment regarding course level, and hopefully my chances of getting some modules ahead of studies are looking better than compared to the other institutes. Don't get me wrong, I don't want to go down the easy route but why should someone sit for "Database 101" or "Principles of OOP" when applying and preaching database normalisation and practicing Clean Code Developer are like flesh and blood? Anyway, I'll be off to get my transcripts of certificates together with my course assignments from the old days at the university. Yes, I studied Applied Chemistry for a couple of years before intersecting into IT and software development particularly... ;-)

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  • Microsoft Business Intelligence Seminar 2011

    - by DavidWimbush
    I was lucky enough to attend the maiden presentation of this at Microsoft Reading yesterday. It was pretty gripping stuff not only because of what was said but also because of what could only be hinted at. Here's what I took away from the day. (Disclaimer: I'm not a BI guru, just a reasonably experienced BI developer, so I may have misunderstood or misinterpreted a few things. Particularly when so much of the talk was about the vision and subtle hints of what is coming. Please comment if you think I've got anything wrong. I'm also not going to even try to cover Master Data Services as I struggled to imagine how you would actually use it.) I was a bit worried when I learned that the whole day was going to be presented by one guy but Rafal Lukawiecki is a very engaging speaker. He's going to be presenting this about 20 times around the world over the coming months. If you get a chance to hear him speak, I say go for it. No doubt some of the hints will become clearer as Denali gets closer to RTM. Firstly, things are definitely happening in the SQL Server Reporting and BI world. Traditionally IT would build a data warehouse, then cubes on top of that, and then publish them in a structured and controlled way. But, just as with many IT projects in general, by the time it's finished the business has moved on and the system no longer meets their requirements. This not sustainable and something more agile is needed but there has to be some control. Apparently we're going to be hearing the catchphrase 'Balancing agility with control' a lot. More users want more access to more data. Can they define what they want? Of course not, but they'll recognise it when they see it. It's estimated that only 28% of potential BI users have meaningful access to the data they need, so there is a real pent-up demand. The answer looks like: give them some self-service tools so they can experiment and see what works, and then IT can help to support the results. It's estimated that 32% of Excel users are comfortable with its analysis tools such as pivot tables. It's the power user's preferred tool. Why fight it? That's why PowerPivot is an Excel add-in and that's why they released a Data Mining add-in for it as well. It does appear that the strategy is going to be to use Reporting Services (in SharePoint mode), PowerPivot, and possibly something new (smiles and hints but no details) to create reports and explore data. Everything will be published and managed in SharePoint which gives users the ability to mash-up, share and socialise what they've found out. SharePoint also gives IT tools to understand what people are looking at and where to concentrate effort. If PowerPivot report X becomes widely used, it's time to check that it shows what they think it does and perhaps get it a bit more under central control. There was more SharePoint detail that went slightly over my head regarding where Excel Services and Excel Web Application fit in, the differences between them, and the suggestion that it is likely they will one day become one (but not in the immediate future). That basic pattern is set to be expanded upon by further exploiting Vertipaq (the columnar indexing engine that enables PowerPivot to store and process a lot of data fast and in a small memory footprint) to provide scalability 'from the desktop to the data centre', and some yet to be detailed advances in 'frictionless deployment' (part of which is about making the difference between local and the cloud pretty much irrelevant). Excel looks like becoming Microsoft's primary BI client. It already has: the ability to consume cubes strong visualisation tools slicers (which are part of Excel not PowerPivot) a data mining add-in PowerPivot A major hurdle for self-service BI is presenting the data in a consumable format. You can't just give users PowerPivot and a server with a copy of the OLTP database(s). Building cubes is labour intensive and doesn't always give the user what they need. This is where the BI Semantic Model (BISM) comes in. I gather it's a layer of metadata you define that can combine multiple data sources (and types of data source) into a clear 'interface' that users can work with. It comes with a new query language called DAX. SSAS cubes are unlikely to go away overnight because, with their pre-calculated results, they are still the most efficient way to work with really big data sets. A few other random titbits that came up: Reporting Services is going to get some good new stuff in Denali. Keep an eye on www.projectbotticelli.com for the slides. You can also view last year's seminar sessions which covered a lot of the same ground as far as the overall strategy is concerned. They plan to add more material as Denali's features are publicly exposed. Check out the PASS keynote address for a showing of Yahoo's SQL BI servers. Apparently they wheeled the rack out on stage still plugged in and running! Check out the Excel 2010 Data Mining Add-Ins. 32 bit only at present but 64 bit is on the way. There are lots of data sets, many of them free, at the Windows Azure Marketplace Data Market (where you can also get ESRI shape files). If you haven't already seen it, have a look at the Silverlight Pivot Viewer (http://weblogs.asp.net/scottgu/archive/2010/06/29/silverlight-pivotviewer-now-available.aspx). The Bing Maps Data Connector is worth a look if you're into spatial stuff (http://www.bing.com/community/site_blogs/b/maps/archive/2010/07/13/data-connector-sql-server-2008-spatial-amp-bing-maps.aspx).  

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  • Changing CSS with jQuery syntax in Silverlight using jLight

    - by Timmy Kokke
    Lately I’ve ran into situations where I had to change elements or had to request a value in the DOM from Silverlight. jLight, which was introduced in an earlier article, can help with that. jQuery offers great ways to change CSS during runtime. Silverlight can access the DOM, but it isn’t as easy as jQuery. All examples shown in this article can be looked at in this online demo. The code can be downloaded here.   Part 1: The easy stuff Selecting and changing properties is pretty straight forward. Setting the text color in all <B> </B> elements can be done using the following code:   jQuery.Select("b").Css("color", "red");   The Css() method is an extension method on jQueryObject which is return by the jQuery.Select() method. The Css() method takes to parameters. The first is the Css style property. All properties used in Css can be entered in this string. The second parameter is the value you want to give the property. In this case the property is “color” and it is changed to “red”. To specify which element you want to select you can add a :selector parameter to the Select() method as shown in the next example.   jQuery.Select("b:first").Css("font-family", "sans-serif");   The “:first” pseudo-class selector selects only the first element. This example changes the “font-family” property of the first <B></B> element to “sans-serif”. To make use of intellisense in Visual Studio I’ve added a extension methods to help with the pseudo-classes. In the example below the “font-weight” of every “Even” <LI></LI> is set to “bold”.   jQuery.Select("li".Even()).Css("font-weight", "bold");   Because the Css() extension method returns a jQueryObject it is possible to chain calls to Css(). The following example show setting the “color”, “background-color” and the “font-size” of all headers in one go.   jQuery.Select(":header").Css("color", "#12FF70") .Css("background-color", "yellow") .Css("font-size", "25px");   Part 2: More complex stuff In only a few cases you need to change only one style property. More often you want to change an entire set op style properties all in one go.  You could chain a lot of Css() methods together. A better way is to add a class to a stylesheet and define all properties in there. With the AddClass() method you can set a style class to a set of elements. This example shows how to add the “demostyle” class to all <B></B> in the document.   jQuery.Select("b").AddClass("demostyle");   Removing the class works in the same way:   jQuery.Select("b").RemoveClass("demostyle");   jLight is build for interacting with to the DOM from Silverlight using jQuery. A jQueryObjectCss object can be used to define different sets of style properties in Silverlight. The over 60 most common Css style properties are defined in the jQueryObjectCss class. A string indexer can be used to access all style properties ( CssObject1[“background-color”] equals CssObject1.BackgroundColor). In the code below, two jQueryObjectCss objects are defined and instantiated.   private jQueryObjectCss CssObject1; private jQueryObjectCss CssObject2;   public Demo2() { CssObject1 = new jQueryObjectCss { BackgroundColor = "Lime", Color="Black", FontSize = "12pt", FontFamily = "sans-serif", FontWeight = "bold", MarginLeft = 150, LineHeight = "28px", Border = "Solid 1px #880000" }; CssObject2 = new jQueryObjectCss { FontStyle = "Italic", FontSize = "48", Color = "#225522" }; InitializeComponent(); }   Now instead of chaining to set all different properties you can just pass one of the jQueryObjectCss objects to the Css() method. In this case all <LI></LI> elements are set to match this object.   jQuery.Select("li").Css(CssObject1); When using the jQueryObjectCss objects chaining is still possible. In the following example all headers are given a blue backgroundcolor and the last is set to match CssObject2.   jQuery.Select(":header").Css(new jQueryObjectCss{BackgroundColor = "Blue"}) .Eq(-1).Css(CssObject2);   Part 3: The fun stuff Having Silverlight call JavaScript and than having JavaScript to call Silverlight requires a lot of plumbing code. Everything has to be registered and strings are passed back and forth to execute the JavaScript. jLight makes this kind of stuff so easy, it becomes fun to use. In a lot of situations jQuery can call a function to decide what to do, setting a style class based on complex expressions for example. jLight can do the same, but the callback methods are defined in Silverlight. This example calls the function() method for each <LI></LI> element. The callback method has to take a jQueryObject, an integer and a string as parameters. In this case jLight differs a bit from the actual jQuery implementation. jQuery uses only the index and the className parameters. A jQueryObject is added to make it simpler to access the attributes and properties of the element. If the text of the listitem starts with a ‘D’ or an ‘M’ the class is set. Otherwise null is returned and nothing happens.   private void button1_Click(object sender, RoutedEventArgs e) { jQuery.Select("li").AddClass(function); }   private string function(jQueryObject obj, int index, string className) { if (obj.Text[0] == 'D' || obj.Text[0] == 'M') return "demostyle"; return null; }   The last thing I would like to demonstrate uses even more Silverlight and less jLight, but demonstrates the power of the combination. Animating a style property using a Storyboard with easing functions. First a dependency property is defined. In this case it is a double named Intensity. By handling the changed event the color is set using jQuery.   public double Intensity { get { return (double)GetValue(IntensityProperty); } set { SetValue(IntensityProperty, value); } }   public static readonly DependencyProperty IntensityProperty = DependencyProperty.Register("Intensity", typeof(double), typeof(Demo3), new PropertyMetadata(0.0, IntensityChanged));   private static void IntensityChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { var i = (byte)(double)e.NewValue; jQuery.Select("span").Css("color", string.Format("#{0:X2}{0:X2}{0:X2}", i)); }   An animation has to be created. This code defines a Storyboard with one keyframe that uses a bounce ease as an easing function. The animation is set to target the Intensity dependency property defined earlier.   private Storyboard CreateAnimation(double value) { Storyboard storyboard = new Storyboard(); var da = new DoubleAnimationUsingKeyFrames(); var d = new EasingDoubleKeyFrame { EasingFunction = new BounceEase(), KeyTime = KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1.0)), Value = value }; da.KeyFrames.Add(d); Storyboard.SetTarget(da, this); Storyboard.SetTargetProperty(da, new PropertyPath(Demo3.IntensityProperty)); storyboard.Children.Add(da); return storyboard; }   Initially the Intensity is set to 128 which results in a gray color. When one of the buttons is pressed, a new animation is created an played. One to animate to black, and one to animate to white.   public Demo3() { InitializeComponent(); Intensity = 128; }   private void button2_Click(object sender, RoutedEventArgs e) { CreateAnimation(255).Begin(); }   private void button3_Click(object sender, RoutedEventArgs e) { CreateAnimation(0).Begin(); }   Conclusion As you can see jLight can make the life of a Silverlight developer a lot easier when accessing the DOM. Almost all jQuery functions that are defined in jLight use the same constructions as described above. I’ve tried to stay as close as possible to the real jQuery. Having JavaScript perform callbacks to Silverlight using jLight will be described in more detail in a future tutorial about AJAX or eventing.

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  • The Business of Winning Innovation: An Exclusive Blog Series

    - by Kerrie Foy
    "The Business of Winning Innovation” is a series of articles authored by Oracle Agile PLM experts on what it takes to make innovation a successful and lucrative competitive advantage. Our customers have proven Agile PLM applications to be enormously flexible and comprehensive, so we’ve launched this article series to showcase some of the most fascinating, value-packed use cases. In this article by Keith Colonna, we kick-off the series by taking a look at the science side of innovation within the Consumer Products industry and how PLM can help companies innovate faster, cheaper, smarter. This article will review how innovation has become the lifeline for growth within consumer products companies and how certain companies are “winning” by creating a competitive advantage for themselves by taking a more enterprise-wide,systematic approach to “innovation”.   Managing the Science of Innovation within the Consumer Products Industry By: Keith Colonna, Value Chain Solution Manager, Oracle The consumer products (CP) industry is very mature and competitive. Most companies within this industry have saturated North America (NA) with their products thus maximizing their NA growth potential. Future growth is expected to come from either expansion outside of North America and/or by way of new ideas and products. Innovation plays an integral role in both of these strategies, whether you’re innovating business processes or the products themselves, and may cause several challenges for the typical CP company, Becoming more innovative is both an art and a science. Most CP companies are very good at the art of coming up with new innovative ideas, but many struggle with perfecting the science aspect that involves the best practice processes that help companies quickly turn ideas into sellable products and services. Symptoms and Causes of Business Pain Struggles associated with the science of innovation show up in a variety of ways, like: · Establishing and storing innovative product ideas and data · Funneling these ideas to the chosen few · Time to market cycle time and on-time launch rates · Success rates, or how often the best idea gets chosen · Imperfect decision making (i.e. the ability to kill projects that are not projected to be winners) · Achieving financial goals · Return on R&D investment · Communicating internally and externally as more outsource partners are added globally · Knowing your new product pipeline and project status These challenges (and others) can be consolidated into three root causes: A lack of visibility Poor data with limited access The inability to truly collaborate enterprise-wide throughout your extended value chain Choose the Right Remedy Product Lifecycle Management (PLM) solutions are uniquely designed to help companies solve these types challenges and their root causes. However, PLM solutions can vary widely in terms of configurability, functionality, time-to-value, etc. Business leaders should evaluate PLM solution in terms of their own business drivers and long-term vision to determine the right fit. Many of these solutions are point solutions that can help you cure only one or two business pains in the short term. Others have been designed to serve other industries with different needs. Then there are those solutions that demo well but are owned by companies that are either unable or unwilling to continuously improve their solution to stay abreast of the ever changing needs of the CP industry to grow through innovation. What the Right PLM Solution Should Do for You Based on more than twenty years working in the CP industry, I recommend investing in a single solution that can help you solve all of the issues associated with the science of innovation in a totally integrated fashion. By integration I mean the (1) integration of the all of the processes associated with the development, maintenance and delivery of your product data, and (2) the integration, or harmonization of this product data with other downstream sources, like ERP, product catalogues and the GS1 Global Data Synchronization Network (or GDSN, which is now a CP industry requirement for doing business with most retailers). The right PLM solution should help you: Increase Revenue. A best practice PLM solution should help a company grow its revenues by consolidating product development cycle-time and helping companies get new and improved products to market sooner. PLM should also eliminate many of the root causes for a product being returned, refused and/or reclaimed (which takes away from top-line growth) by creating an enterprise-wide, collaborative, workflow-driven environment. Reduce Costs. A strong PLM solution should help shave many unnecessary costs that companies typically take for granted. Rationalizing SKU’s, components (ingredients and packaging) and suppliers is a major opportunity at most companies that PLM should help address. A natural outcome of this rationalization is lower direct material spend and a reduction of inventory. Another cost cutting opportunity comes with PLM when it helps companies avoid certain costs associated with process inefficiencies that lead to scrap, rework, excess and obsolete inventory, poor end of life administration, higher cost of quality and regulatory and increased expediting. Mitigate Risk. Risks are the hardest to quantify but can be the most costly to a company. Food safety, recalls, line shutdowns, customer dissatisfaction and, worst of all, the potential tarnishing of your brands are a few of the debilitating risks that CP companies deal with on a daily basis. These risks are so uniquely severe that they require an enterprise PLM solution specifically designed for the CP industry that safeguards product information and processes while still allowing the art of innovation to flourish. Many CP companies have already created a winning advantage by leveraging a single, best practice PLM solution to establish an enterprise-wide, systematic approach to innovation. Oracle’s Answer for the Consumer Products Industry Oracle is dedicated to solving the growth and innovation challenges facing the CP industry. Oracle’s Agile Product Lifecycle Management for Process solution was originally developed with and for CP companies and is driven by a specialized development staff solely focused on maintaining and continuously improving the solution per the latest industry requirements. Agile PLM for Process helps CP companies handle all of the processes associated with managing the science of the innovation process, including: specification management, new product development/project and portfolio management, formulation optimization, supplier management, and quality and regulatory compliance to name a few. And as I mentioned earlier, integration is absolutely critical. Many Oracle CP customers, both with Oracle ERP systems and non-Oracle ERP systems, report benefits from Oracle’s Agile PLM for Process. In future articles we will explain in greater detail how both existing Oracle customers (like Gallo, Smuckers, Land-O-Lakes and Starbucks) and new Oracle customers (like ConAgra, Tyson, McDonalds and Heinz) have all realized the benefits of Agile PLM for Process and its integration to their ERP systems. More to Come Stay tuned for more articles in our blog series “The Business of Winning Innovation.” While we will also feature articles focused on other industries, look forward to more on how Agile PLM for Process addresses innovation challenges facing the CP industry. Additional topics include: Innovation Data Management (IDM), New Product Development (NPD), Product Quality Management (PQM), Menu Management,Private Label Management, and more! . Watch this video for more info about Agile PLM for Process

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  • ANTS Memory Profiler 7.0

    - by James Michael Hare
    I had always been a fan of ANTS products (Reflector is absolutely invaluable, and their performance profiler is great as well – very easy to use!), so I was curious to see what the ANTS Memory Profiler could show me. Background While a performance profiler will track how much time is typically spent in each unit of code, a memory profiler gives you much more detail on how and where your memory is being consumed and released in a program. As an example, I’d been working on a data access layer at work to call a market data web service.  This web service would take a list of symbols to quote and would return back the quote data.  To help consolidate the thousands of web requests per second we get and reduce load on the web services, we implemented a 5-second cache of quote data.  Not quite long enough to where customers will typically notice a quote go “stale”, but just long enough to be able to collapse multiple quote requests for the same symbol in a short period of time. A 5-second cache may not sound like much, but it actually pays off by saving us roughly 42% of our web service calls, while still providing relatively up-to-date information.  The question is whether or not the extra memory involved in maintaining the cache was worth it, so I decided to fire up the ANTS Memory Profiler and take a look at memory usage. First Impressions The main thing I’ve always loved about the ANTS tools is their ease of use.  Pretty much everything is right there in front of you in a way that makes it easy for you to find what you need with little digging required.  I’ve worked with other, older profilers before (that shall remain nameless other than to hint it was created by a very large chip maker) where it was a mind boggling experience to figure out how to do simple tasks. Not so with AMP.  The opening dialog is very straightforward.  You can choose from here whether to debug an executable, a web application (either in IIS or from VS’s web development server), windows services, etc. So I chose a .NET Executable and navigated to the build location of my test harness.  Then began profiling. At this point while the application is running, you can see a chart of the memory as it ebbs and wanes with allocations and collections.  At any given point in time, you can take snapshots (to compare states) zoom in, or choose to stop at any time.  Snapshots Taking a snapshot also gives you a breakdown of the managed memory heaps for each generation so you get an idea how many objects are staying around for extended periods of time (as an object lives and survives collections, it gets promoted into higher generations where collection becomes less frequent). Generating a snapshot brings up an analysis view with very handy graphs that show your generation sizes.  Almost all my memory is in Generation 1 in the managed memory component of the first graph, which is good news to me, because Gen 2 collections are much rarer.  I once3 made the mistake once of caching data for 30 minutes and found it didn’t get collected very quick after I released my reference because it had been promoted to Gen 2 – doh! Analysis It looks like (from the second pie chart) that the majority of the allocations were in the string class.  This also is expected for me because the majority of the memory allocated is in the web service responses, so it doesn’t seem the entities I’m adapting to (to prevent being too tightly coupled to the web service proxy classes, which can change easily out from under me) aren’t taking a significant portion of memory. I also appreciate that they have clear summary text in key places such as “No issues with large object heap fragmentation were detected”.  For novice users, this type of summary information can be critical to getting them to use a tool and develop a good working knowledge of it. There is also a handy link at the bottom for “What to look for on the summary” which loads a web page of help on key points to look for. Clicking over to the session overview, it’s easy to compare the samples at each snapshot to see how your memory is growing, shrinking, or staying relatively the same.  Looking at my snapshots, I’m pretty happy with the fact that memory allocation and heap size seems to be fairly stable and in control: Once again, you can check on the large object heap, generation one heap, and generation two heap across each snapshot to spot trends. Back on the analysis tab, we can go to the [Class List] button to get an idea what classes are making up the majority of our memory usage.  As was little surprise to me, System.String was the clear majority of my allocations, though I found it surprising that the System.Reflection.RuntimeMehtodInfo came in second.  I was curious about this, so I selected it and went into the [Instance Categorizer].  This view let me see where these instances to RuntimeMehtodInfo were coming from. So I scrolled back through the graph, and discovered that these were being held by the System.ServiceModel.ChannelFactoryRefCache and I was satisfied this was just an artifact of my WCF proxy. I also like that down at the bottom of the Instance Categorizer it gives you a series of filters and offers to guide you on which filter to use based on the problem you are trying to find.  For example, if I suspected a memory leak, I might try to filter for survivors in growing classes.  This means that for instances of a class that are growing in memory (more are being created than cleaned up), which ones are survivors (not collected) from garbage collection.  This might allow me to drill down and find places where I’m holding onto references by mistake and not freeing them! Finally, if you want to really see all your instances and who is holding onto them (preventing collection), you can go to the “Instance Retention Graph” which creates a graph showing what references are being held in memory and who is holding onto them. Visual Studio Integration Of course, VS has its own profiler built in – and for a free bundled profiler it is quite capable – but AMP gives a much cleaner and easier-to-use experience, and when you install it you also get the option of letting it integrate directly into VS. So once you go back into VS after installation, you’ll notice an ANTS menu which lets you launch the ANTS profiler directly from Visual Studio.   Clicking on one of these options fires up the project in the profiler immediately, allowing you to get right in.  It doesn’t integrate with the Visual Studio windows themselves (like the VS profiler does), but still the plethora of information it provides and the clear and concise manner in which it presents it makes it well worth it. Summary If you like the ANTS series of tools, you shouldn’t be disappointed with the ANTS Memory Profiler.  It was so easy to use that I was able to jump in with very little product knowledge and get the information I was looking it for. I’ve used other profilers before that came with 3-inch thick tomes that you had to read in order to get anywhere with the tool, and this one is not like that at all.  It’s built for your everyday developer to get in and find their problems quickly, and I like that! Tweet Technorati Tags: Influencers,ANTS,Memory,Profiler

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  • Cost Comparison Hard Disk Drive to Solid State Drive on Price per Gigabyte - dispelling a myth!

    - by tonyrogerson
    It is often said that Hard Disk Drive storage is significantly cheaper per GiByte than Solid State Devices – this is wholly inaccurate within the database space. People need to look at the cost of the complete solution and not just a single component part in isolation to what is really required to meet the business requirement. Buying a single Hitachi Ultrastar 600GB 3.5” SAS 15Krpm hard disk drive will cost approximately £239.60 (http://scan.co.uk, 22nd March 2012) compared to an OCZ 600GB Z-Drive R4 CM84 PCIe costing £2,316.54 (http://scan.co.uk, 22nd March 2012); I’ve not included FusionIO ioDrive because there is no public pricing available for it – something I never understand and personally when companies do this I immediately think what are they hiding, luckily in FusionIO’s case the product is proven though is expensive compared to OCZ enterprise offerings. On the face of it the single 15Krpm hard disk has a price per GB of £0.39, the SSD £3.86; this is what you will see in the press and this is what sales people will use in comparing the two technologies – do not be fooled by this bullshit people! What is the requirement? The requirement is the database will have a static size of 400GB kept static through archiving so growth and trim will balance the database size, the client requires resilience, there will be several hundred call centre staff querying the database where queries will read a small amount of data but there will be no hot spot in the data so the randomness will come across the entire 400GB of the database, estimates predict that the IOps required will be approximately 4,000IOps at peak times, because it’s a call centre system the IO latency is important and must remain below 5ms per IO. The balance between read and write is 70% read, 30% write. The requirement is now defined and we have three of the most important pieces of the puzzle – space required, estimated IOps and maximum latency per IO. Something to consider with regard SQL Server; write activity requires synchronous IO to the storage media specifically the transaction log; that means the write thread will wait until the IO is completed and hardened off until the thread can continue execution, the requirement has stated that 30% of the system activity will be write so we can expect a high amount of synchronous activity. The hardware solution needs to be defined; two possible solutions: hard disk or solid state based; the real question now is how many hard disks are required to achieve the IO throughput, the latency and resilience, ditto for the solid state. Hard Drive solution On a test on an HP DL380, P410i controller using IOMeter against a single 15Krpm 146GB SAS drive, the throughput given on a transfer size of 8KiB against a 40GiB file on a freshly formatted disk where the partition is the only partition on the disk thus the 40GiB file is on the outer edge of the drive so more sectors can be read before head movement is required: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 3,733 IOps at an average latency of 34.06ms (34 MiB/s). The same test was done on the same disk but the test file was 130GiB: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 528 IOps at an average latency of 217.49ms (4 MiB/s). From the result it is clear random performance gets worse as the disk fills up – I’m currently writing an article on short stroking which will cover this in detail. Given the work load is random in nature looking at the random performance of the single drive when only 40 GiB of the 146 GB is used gives near the IOps required but the latency is way out. Luckily I have tested 6 x 15Krpm 146GB SAS 15Krpm drives in a RAID 0 using the same test methodology, for the same test above on a 130 GiB for each drive added the performance boost is near linear, for each drive added throughput goes up by 5 MiB/sec, IOps by 700 IOps and latency reducing nearly 50% per drive added (172 ms, 94 ms, 65 ms, 47 ms, 37 ms, 30 ms). This is because the same 130GiB is spread out more as you add drives 130 / 1, 130 / 2, 130 / 3 etc. so implicit short stroking is occurring because there is less file on each drive so less head movement required. The best latency is still 30 ms but we have the IOps required now, but that’s on a 130GiB file and not the 400GiB we need. Some reality check here: a) the drive randomness is more likely to be 50/50 and not a full 100% but the above has highlighted the effect randomness has on the drive and the more a drive fills with data the worse the effect. For argument sake let us assume that for the given workload we need 8 disks to do the job, for resilience reasons we will need 16 because we need to RAID 1+0 them in order to get the throughput and the resilience, RAID 5 would degrade performance. Cost for hard drives: 16 x £239.60 = £3,833.60 For the hard drives we will need disk controllers and a separate external disk array because the likelihood is that the server itself won’t take the drives, a quick spec off DELL for a PowerVault MD1220 which gives the dual pathing with 16 disks 146GB 15Krpm 2.5” disks is priced at £7,438.00, note its probably more once we had two controller cards to sit in the server in, racking etc. Minimum cost taking the DELL quote as an example is therefore: {Cost of Hardware} / {Storage Required} £7,438.60 / 400 = £18.595 per GB £18.59 per GiB is a far cry from the £0.39 we had been told by the salesman and the myth. Yes, the storage array is composed of 16 x 146 disks in RAID 10 (therefore 8 usable) giving an effective usable storage availability of 1168GB but the actual storage requirement is only 400 and the extra disks have had to be purchased to get the  IOps up. Solid State Drive solution A single card significantly exceeds the IOps and latency required, for resilience two will be required. ( £2,316.54 * 2 ) / 400 = £11.58 per GB With the SSD solution only two PCIe sockets are required, no external disk units, no additional controllers, no redundant controllers etc. Conclusion I hope by showing you an example that the myth that hard disk drives are cheaper per GiB than Solid State has now been dispelled - £11.58 per GB for SSD compared to £18.59 for Hard Disk. I’ve not even touched on the running costs, compare the costs of running 18 hard disks, that’s a lot of heat and power compared to two PCIe cards!Just a quick note: I've left a fair amount of information out due to this being a blog! If in doubt, email me :)I'll also deal with the myth that SSD's wear out at a later date as well - that's just way over done still, yes, 5 years ago, but now - no.

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  • IE9 not rendering box-shadow Elements inside of Table Cells

    - by Rick Strahl
    Ran into an annoying problem today with IE 9. Slowly updating some older sites with CSS 3 tags and for the most part IE9 does a reasonably decent job of working with the new CSS 3 features. Not all by a long shot but at least some of the more useful ones like border-radius and box-shadow are supported. Until today I was happy to see that IE supported box-shadow just fine, but I ran into a problem with some old markup that uses tables for its main layout sections. I found that inside of a table cell IE fails to render a box-shadow. Below are images from Chrome (left) and IE 9 (right) of the same content: The download and purchase images are rendered with: <a href="download.asp" style="display:block;margin: 10px;"><img src="../images/download.gif" class="boxshadow roundbox" /></a> where the .boxshadow and .roundbox styles look like this:.boxshadow { -moz-box-shadow: 3px 3px 5px #535353; -webkit-box-shadow: 3px 3px 5px #535353; box-shadow: 3px 3px 5px #535353; } .roundbox { -moz-border-radius: 6px 6px 6px 6px; -webkit-border-radius: 6px; border-radius: 6px 6px 6px 6px; } And the Problem is… collapsed Table Borders Now normally these two styles work just fine in IE 9 when applied to elements. But the box-shadow doesn't work inside of this markup - because the parent container is a table cell.<td class="sidebar" style="border-collapse: collapse"> … <a href="download.asp" style="display:block;margin: 10px;"><img src="../images/download.gif" class="boxshadow roundbox" /></a> …</td> This HTML causes the image to not show a shadow. In actuality I'm not styling inline, but as part of my browser Reset I have the following in my master .css file:table { border-collapse: collapse; border-spacing: 0; } which has the same effect as the inline style. border-collapse by default inherits from the parent and so the TD inherits from table and tr - so TD tags are effectively collapsed. You can check out a test document that demonstrates this behavior here in this CodePaste.net snippet or run it here. How to work around this Issue To get IE9 to render the shadows inside of the TD tag correctly, I can just change the style explicitly NOT to use border-collapse:<td class="sidebar" style="border-collapse: separate; border-width: 0;"> Or better yet (thanks to David's comment below), you can add the border-collapse: separate to the .boxshadow style like this:.boxshadow { -moz-box-shadow: 3px 3px 5px #535353; -webkit-box-shadow: 3px 3px 5px #535353; box-shadow: 3px 3px 5px #535353; border-collapse: separate; } With either of these approaches IE renders the shadows correctly. Do you really need border-collapse? Should you bother with border-collapse? I think so! Collapsed borders render flat as a single fat line if a border-width and border-color are assigned, while separated borders render a thin line with a bunch of weird white space around it or worse render a old skool 3D raised border which is terribly ugly as well. So as a matter of course in any app my browser Reset includes the above code to make sure all tables with borders render the same flat borders. As you probably know, IE has all sorts of rendering issues in tables and on backgrounds (opacity backgrounds or image backgrounds) most of which is caused by the way that IE internally uses ActiveX filters to apply these effects. Apparently collapsed borders are yet one more item that causes problems with rendering. There you have it. Another crappy failure in IE we have to check for now, just one more reason to hate Internet Explorer. Luckily this one has a reasonably easy workaround. I hope this helps out somebody and saves them the hour I spent trying to figure out what caused this problem in the first place. Resources Sample HTML document that demonstrates the behavior Run the Sample© Rick Strahl, West Wind Technologies, 2005-2012Posted in HTML  Internet Explorer   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • Oracle Flashback Technologies - Overview

    - by Sridhar_R-Oracle
    Oracle Flashback Technologies - IntroductionIn his May 29th 2014 blog, my colleague Joe Meeks introduced Oracle Maximum Availability Architecture (MAA) and discussed both planned and unplanned outages. Let’s take a closer look at unplanned outages. These can be caused by physical failures (e.g., server, storage, network, file deletion, physical corruption, site failures) or by logical failures – cases where all components and files are physically available, but data is incorrect or corrupt. These logical failures are usually caused by human errors or application logic errors. This blog series focuses on these logical errors – what causes them and how to address and recover from them using Oracle Database Flashback. In this introductory blog post, I’ll provide an overview of the Oracle Database Flashback technologies and will discuss the features in detail in future blog posts. Let’s get started. We are all human beings (unless a machine is reading this), and making mistakes is a part of what we do…often what we do best!  We “fat finger”, we spill drinks on keyboards, unplug the wrong cables, etc.  In addition, many of us, in our lives as DBAs or developers, must have observed, caused, or corrected one or more of the following unpleasant events: Accidentally updated a table with wrong values !! Performed a batch update that went wrong - due to logical errors in the code !! Dropped a table !! How do DBAs typically recover from these types of errors? First, data needs to be restored and recovered to the point-in-time when the error occurred (incomplete or point-in-time recovery).  Moreover, depending on the type of fault, it’s possible that some services – or even the entire database – would have to be taken down during the recovery process.Apart from error conditions, there are other questions that need to be addressed as part of the investigation. For example, what did the data look like in the morning, prior to the error? What were the various changes to the row(s) between two timestamps? Who performed the transaction and how can it be reversed?  Oracle Database includes built-in Flashback technologies, with features that address these challenges and questions, and enable you to perform faster, easier, and convenient recovery from logical corruptions. HistoryFlashback Query, the first Flashback Technology, was introduced in Oracle 9i. It provides a simple, powerful and completely non-disruptive mechanism for data verification and recovery from logical errors, and enables users to view the state of data at a previous point in time.Flashback Technologies were further enhanced in Oracle 10g, to provide fast, easy recovery at the database, table, row, and even at a transaction level.Oracle Database 11g introduced an innovative method to manage and query long-term historical data with Flashback Data Archive. The 11g release also introduced Flashback Transaction, which provides an easy, one-step operation to back out a transaction. Oracle Database versions 11.2.0.2 and beyond further enhanced the performance of these features. Note that all the features listed here work without requiring any kind of restore operation.In addition, Flashback features are fully supported with the new multi-tenant capabilities introduced with Oracle Database 12c, Flashback Features Oracle Flashback Database enables point-in-time-recovery of the entire database without requiring a traditional restore and recovery operation. It rewinds the entire database to a specified point in time in the past by undoing all the changes that were made since that time.Oracle Flashback Table enables an entire table or a set of tables to be recovered to a point in time in the past.Oracle Flashback Drop enables accidentally dropped tables and all dependent objects to be restored.Oracle Flashback Query enables data to be viewed at a point-in-time in the past. This feature can be used to view and reconstruct data that was lost due to unintentional change(s) or deletion(s). This feature can also be used to build self-service error correction into applications, empowering end-users to undo and correct their errors.Oracle Flashback Version Query offers the ability to query the historical changes to data between two points in time or system change numbers (SCN) Oracle Flashback Transaction Query enables changes to be examined at the transaction level. This capability can be used to diagnose problems, perform analysis, audit transactions, and even revert the transaction by undoing SQLOracle Flashback Transaction is a procedure used to back-out a transaction and its dependent transactions.Flashback technologies eliminate the need for a traditional restore and recovery process to fix logical corruptions or make enquiries. Using these technologies, you can recover from the error in the same amount of time it took to generate the error. All the Flashback features can be accessed either via SQL command line (or) via Enterprise Manager.  Most of the Flashback technologies depend on the available UNDO to retrieve older data. The following table describes the various Flashback technologies: their purpose, dependencies and situations where each individual technology can be used.   Example Syntax Error investigation related:The purpose is to investigate what went wrong and what the values were at certain points in timeFlashback Queries  ( select .. as of SCN | Timestamp )   - Helps to see the value of a row/set of rows at a point in timeFlashback Version Queries  ( select .. versions between SCN | Timestamp and SCN | Timestamp)  - Helps determine how the value evolved between certain SCNs or between timestamps Flashback Transaction Queries (select .. XID=)   - Helps to understand how the transaction caused the changes.Error correction related:The purpose is to fix the error and correct the problems,Flashback Table  (flashback table .. to SCN | Timestamp)  - To rewind the table to a particular timestamp or SCN to reverse unwanted updates Flashback Drop (flashback table ..  to before drop )  - To undrop or undelete a table Flashback Database (flashback database to SCN  | Restore Point )  - This is the rewind button for Oracle databases. You can revert the entire database to a particular point in time. It is a fast way to perform a PITR (point-in-time recovery). Flashback Transaction (DBMS_FLASHBACK.TRANSACTION_BACKOUT(XID..))  - To reverse a transaction and its related transactions Advanced use cases Flashback technology is integrated into Oracle Recovery Manager (RMAN) and Oracle Data Guard. So, apart from the basic use cases mentioned above, the following use cases are addressed using Oracle Flashback. Block Media recovery by RMAN - to perform block level recovery Snapshot Standby - where the standby is temporarily converted to a read/write environment for testing, backup, or migration purposes Re-instate old primary in a Data Guard environment – this avoids the need to restore an old backup and perform a recovery to make it a new standby. Guaranteed Restore Points - to bring back the entire database to an older point-in-time in a guaranteed way. and so on..I hope this introductory overview helps you understand how Flashback features can be used to investigate and recover from logical errors.  As mentioned earlier, I will take a deeper-dive into to some of the critical Flashback features in my upcoming blogs and address common use cases.

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  • Guide to MySQL & NoSQL, Webinar Q&A

    - by Mat Keep
    0 0 1 959 5469 Homework 45 12 6416 14.0 Normal 0 false false false EN-US JA X-NONE /* 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-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} Yesterday we ran a webinar discussing the demands of next generation web services and how blending the best of relational and NoSQL technologies enables developers and architects to deliver the agility, performance and availability needed to be successful. Attendees posted a number of great questions to the MySQL developers, serving to provide additional insights into areas like auto-sharding and cross-shard JOINs, replication, performance, client libraries, etc. So I thought it would be useful to post those below, for the benefit of those unable to attend the webinar. Before getting to the Q&A, there are a couple of other resources that maybe useful to those looking at NoSQL capabilities within MySQL: - On-Demand webinar (coming soon!) - Slides used during the webinar - Guide to MySQL and NoSQL whitepaper  - MySQL Cluster demo, including NoSQL interfaces, auto-sharing, high availability, etc.  So here is the Q&A from the event  Q. Where does MySQL Cluster fit in to the CAP theorem? A. MySQL Cluster is flexible. A single Cluster will prefer consistency over availability in the presence of network partitions. A pair of Clusters can be configured to prefer availability over consistency. A full explanation can be found on the MySQL Cluster & CAP Theorem blog post.  Q. Can you configure the number of replicas? (the slide used a replication factor of 1) Yes. A cluster is configured by an .ini file. The option NoOfReplicas sets the number of originals and replicas: 1 = no data redundancy, 2 = one copy etc. Usually there's no benefit in setting it >2. Q. Interestingly most (if not all) of the NoSQL databases recommend having 3 copies of data (the replication factor).    Yes, with configurable quorum based Reads and writes. MySQL Cluster does not need a quorum of replicas online to provide service. Systems that require a quorum need > 2 replicas to be able to tolerate a single failure. Additionally, many NoSQL systems take liberal inspiration from the original GFS paper which described a 3 replica configuration. MySQL Cluster avoids the need for a quorum by using a lightweight arbitrator. You can configure more than 2 replicas, but this is a tradeoff between incrementally improved availability, and linearly increased cost. Q. Can you have cross node group JOINS? Wouldn't that run into the risk of flooding the network? MySQL Cluster 7.2 supports cross nodegroup joins. A full cross-join can require a large amount of data transfer, which may bottleneck on network bandwidth. However, for more selective joins, typically seen with OLTP and light analytic applications, cross node-group joins give a great performance boost and network bandwidth saving over having the MySQL Server perform the join. Q. Are the details of the benchmark available anywhere? According to my calculations it results in approx. 350k ops/sec per processor which is the largest number I've seen lately The details are linked from Mikael Ronstrom's blog The benchmark uses a benchmarking tool we call flexAsynch which runs parallel asynchronous transactions. It involved 100 byte reads, of 25 columns each. Regarding the per-processor ops/s, MySQL Cluster is particularly efficient in terms of throughput/node. It uses lock-free minimal copy message passing internally, and maximizes ID cache reuse. Note also that these are in-memory tables, there is no need to read anything from disk. Q. Is access control (like table) planned to be supported for NoSQL access mode? Currently we have not seen much need for full SQL-like access control (which has always been overkill for web apps and telco apps). So we have no plans, though especially with memcached it is certainly possible to turn-on connection-level access control. But specifically table level controls are not planned. Q. How is the performance of memcached APi with MySQL against memcached+MySQL or any other Object Cache like Ecache with MySQL DB? With the memcache API we generally see a memcached response in less than 1 ms. and a small cluster with one memcached server can handle tens of thousands of operations per second. Q. Can .NET can access MemcachedAPI? Yes, just use a .Net memcache client such as the enyim or BeIT memcache libraries. Q. Is the row level locking applicable when you update a column through memcached API? An update that comes through memcached uses a row lock and then releases it immediately. Memcached operations like "INCREMENT" are actually pushed down to the data nodes. In most cases the locks are not even held long enough for a network round trip. Q. Has anyone published an example using something like PHP? I am assuming that you just use the PHP memcached extension to hook into the memcached API. Is that correct? Not that I'm aware of but absolutely you can use it with php or any of the other drivers Q. For beginner we need more examples. Take a look here for a fully worked example Q. Can I access MySQL using Cobol (Open Cobol) or C and if so where can I find the coding libraries etc? A. There is a cobol implementation that works well with MySQL, but I do not think it is Open Cobol. Also there is a MySQL C client library that is a standard part of every mysql distribution Q. Is there a place to go to find help when testing and/implementing the NoSQL access? If using Cluster then you can use the [email protected] alias or post on the MySQL Cluster forum Q. Are there any white papers on this?  Yes - there is more detail in the MySQL Guide to NoSQL whitepaper If you have further questions, please don’t hesitate to use the comments below!

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  • T4 Performance Counters explained

    - by user13346607
    Now that T4 is out for a few month some people might have wondered what details of the new pipeline you can monitor. A "cpustat -h" lists a lot of events that can be monitored, and only very few are self-explanatory. I will try to give some insight on all of them, some of these "PIC events" require an in-depth knowledge of T4 pipeline. Over time I will try to explain these, for the time being these events should simply be ignored. (Side note: some counters changed from tape-out 1.1 (*only* used in the T4 beta program) to tape-out 1.2 (used in the systems shipping today) The table only lists the tape-out 1.2 counters) 0 0 1 1058 6033 Oracle Microelectronics 50 14 7077 14.0 Normal 0 false false false EN-US JA X-NONE /* 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-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} pic name (cpustat) Prose Comment Sel-pipe-drain-cycles, Sel-0-[wait|ready], Sel-[1,2] Sel-0-wait counts cycles a strand waits to be selected. Some reasons can be counted in detail; these are: Sel-0-ready: Cycles a strand was ready but not selected, that can signal pipeline oversubscription Sel-1: Cycles only one instruction or µop was selected Sel-2: Cycles two instructions or µops were selected Sel-pipe-drain-cycles: cf. PRM footnote 8 to table 10.2 Pick-any, Pick-[0|1|2|3] Cycles one, two, three, no or at least one instruction or µop is picked Instr_FGU_crypto Number of FGU or crypto instructions executed on that vcpu Instr_ld dto. for load Instr_st dto. for store SPR_ring_ops dto. for SPR ring ops Instr_other dto. for all other instructions not listed above, PRM footnote 7 to table 10.2 lists the instructions Instr_all total number of instructions executed on that vcpu Sw_count_intr Nr of S/W count instructions on that vcpu (sethi %hi(fc000),%g0 (whatever that is))  Atomics nr of atomic ops, which are LDSTUB/a, CASA/XA, and SWAP/A SW_prefetch Nr of PREFETCH or PREFETCHA instructions Block_ld_st Block loads or store on that vcpu IC_miss_nospec, IC_miss_[L2_or_L3|local|remote]\ _hit_nospec Various I$ misses, distinguished by where they hit. All of these count per thread, but only primary events: T4 counts only the first occurence of an I$ miss on a core for a certain instruction. If one strand misses in I$ this miss is counted, but if a second strand on the same core misses while the first miss is being resolved, that second miss is not counted This flavour of I$ misses counts only misses that are caused by instruction that really commit (note the "_nospec") BTC_miss Branch target cache miss ITLB_miss ITLB misses (synchronously counted) ITLB_miss_asynch dto. but asynchronously [I|D]TLB_fill_\ [8KB|64KB|4MB|256MB|2GB|trap] H/W tablewalk events that fill ITLB or DTLB with translation for the corresponding page size. The “_trap” event occurs if the HWTW was not able to fill the corresponding TLB IC_mtag_miss, IC_mtag_miss_\ [ptag_hit|ptag_miss|\ ptag_hit_way_mismatch] I$ micro tag misses, with some options for drill down Fetch-0, Fetch-0-all fetch-0 counts nr of cycles nothing was fetched for this particular strand, fetch-0-all counts cycles nothing was fetched for all strands on a core Instr_buffer_full Cycles the instruction buffer for a strand was full, thereby preventing any fetch BTC_targ_incorrect Counts all occurences of wrongly predicted branch targets from the BTC [PQ|ROB|LB|ROB_LB|SB|\ ROB_SB|LB_SB|RB_LB_SB|\ DTLB_miss]\ _tag_wait ST_q_tag_wait is listed under sl=20. These counters monitor pipeline behaviour therefore they are not strand specific: PQ_...: cycles Rename stage waits for a Pick Queue tag (might signal memory bound workload for single thread mode, cf. Mail from Richard Smith) ROB_...: cycles Select stage waits for a ROB (ReOrderBuffer) tag LB_...: cycles Select stage waits for a Load Buffer tag SB_...: cycles Select stage waits for Store Buffer tag combinations of the above are allowed, although some of these events can overlap, the counter will only be incremented once per cycle if any of these occur DTLB_...: cycles load or store instructions wait at Pick stage for a DTLB miss tag [ID]TLB_HWTW_\ [L2_hit|L3_hit|L3_miss|all] Counters for HWTW accesses caused by either DTLB or ITLB misses. Canbe further detailed by where they hit IC_miss_L2_L3_hit, IC_miss_local_remote_remL3_hit, IC_miss I$ prefetches that were dropped because they either miss in L2$ or L3$ This variant counts misses regardless if the causing instruction commits or not DC_miss_nospec, DC_miss_[L2_L3|local|remote_L3]\ _hit_nospec D$ misses either in general or detailed by where they hit cf. the explanation for the IC_miss in two flavours for an explanation of _nospec and the reasoning for two DC_miss counters DTLB_miss_asynch counts all DTLB misses asynchronously, there is no way to count them synchronously DC_pref_drop_DC_hit, SW_pref_drop_[DC_hit|buffer_full] L1-D$ h/w prefetches that were dropped because of a D$ hit, counted per core. The others count software prefetches per strand [Full|Partial]_RAW_hit_st_[buf|q] Count events where a load wants to get data that has not yet been stored, i. e. it is still inside the pipeline. The data might be either still in the store buffer or in the store queue. If the load's data matches in the SB and in the store queue the data in buffer takes precedence of course since it is younger [IC|DC]_evict_invalid, [IC|DC|L1]_snoop_invalid, [IC|DC|L1]_invalid_all Counter for invalidated cache evictions per core St_q_tag_wait Number of cycles pipeline waits for a store queue tag, of course counted per core Data_pref_[drop_L2|drop_L3|\ hit_L2|hit_L3|\ hit_local|hit_remote] Data prefetches that can be further detailed by either why they were dropped or where they did hit St_hit_[L2|L3], St_L2_[local|remote]_C2C, St_local, St_remote Store events distinguished by where they hit or where they cause a L2 cache-to-cache transfer, i.e. either a transfer from another L2$ on the same die or from a different die DC_miss, DC_miss_\ [L2_L3|local|remote]_hit D$ misses either in general or detailed by where they hit cf. the explanation for the IC_miss in two flavours for an explanation of _nospec and the reasoning for two DC_miss counters L2_[clean|dirty]_evict Per core clean or dirty L2$ evictions L2_fill_buf_full, L2_wb_buf_full, L2_miss_buf_full Per core L2$ buffer events, all count number of cycles that this state was present L2_pipe_stall Per core cycles pipeline stalled because of L2$ Branches Count branches (Tcc, DONE, RETRY, and SIT are not counted as branches) Br_taken Counts taken branches (Tcc, DONE, RETRY, and SIT are not counted as branches) Br_mispred, Br_dir_mispred, Br_trg_mispred, Br_trg_mispred_\ [far_tbl|indir_tbl|ret_stk] Counter for various branch misprediction events.  Cycles_user counts cycles, attribute setting hpriv, nouser, sys controls addess space to count in Commit-[0|1|2], Commit-0-all, Commit-1-or-2 Number of times either no, one, or two µops commit for a strand. Commit-0-all counts number of times no µop commits for the whole core, cf. footnote 11 to table 10.2 in PRM for a more detailed explanation on how this counters interacts with the privilege levels

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  • SQL University: What and why of database refactoring

    - by Mladen Prajdic
    This is a post for a great idea called SQL University started by Jorge Segarra also famously known as SqlChicken on Twitter. It’s a collection of blog posts on different database related topics contributed by several smart people all over the world. So this week is mine and we’ll be talking about database testing and refactoring. In 3 posts we’ll cover: SQLU part 1 - What and why of database testing SQLU part 2 - What and why of database refactoring SQLU part 3 - Tools of the trade This is a second part of the series and in it we’ll take a look at what database refactoring is and why do it. Why refactor a database To know why refactor we first have to know what refactoring actually is. Code refactoring is a process where we change module internals in a way that does not change that module’s input/output behavior. For successful refactoring there is one crucial thing we absolutely must have: Tests. Automated unit tests are the only guarantee we have that we haven’t broken the input/output behavior before refactoring. If you haven’t go back ad read my post on the matter. Then start writing them. Next thing you need is a code module. Those are views, UDFs and stored procedures. By having direct table access we can kiss fast and sweet refactoring good bye. One more point to have a database abstraction layer. And no, ORM’s don’t fall into that category. But also know that refactoring is NOT adding new functionality to your code. Many have fallen into this trap. Don’t be one of them and resist the lure of the dark side. And it’s a strong lure. We developers in general love to add new stuff to our code, but hate fixing our own mistakes or changing existing code for no apparent reason. To be a good refactorer one needs discipline and focus. Now we know that refactoring is all about changing inner workings of existing code. This can be due to performance optimizations, changing internal code workflows or some other reason. This is a typical black box scenario to the outside world. If we upgrade the car engine it still has to drive on the road (preferably faster) and not fly (no matter how cool that would be). Also be aware that white box tests will break when we refactor. What to refactor in a database Refactoring databases doesn’t happen that often but when it does it can include a lot of stuff. Let us look at a few common cases. Adding or removing database schema objects Adding, removing or changing table columns in any way, adding constraints, keys, etc… All of these can be counted as internal changes not visible to the data consumer. But each of these carries a potential input/output behavior change. Dropping a column can result in views not working anymore or stored procedure logic crashing. Adding a unique constraint shows duplicated data that shouldn’t exist. Foreign keys break a truncate table command executed from an application that runs once a month. All these scenarios are very real and can happen. With the proper database abstraction layer fully covered with black box tests we can make sure something like that does not happen (hopefully at all). Changing physical structures Physical structures include heaps, indexes and partitions. We can pretty much add or remove those without changing the data returned by the database. But the performance can be affected. So here we use our performance tests. We do have them, right? Just by adding a single index we can achieve orders of magnitude performance improvement. Won’t that make users happy? But what if that index causes our write operations to crawl to a stop. again we have to test this. There are a lot of things to think about and have tests for. Without tests we can’t do successful refactoring! Fixing bad code We all have some bad code in our systems. We usually refer to that code as code smell as they violate good coding practices. Examples of such code smells are SQL injection, use of SELECT *, scalar UDFs or cursors, etc… Each of those is huge code smell and can result in major code changes. Take SELECT * from example. If we remove a column from a table the client using that SELECT * statement won’t have a clue about that until it runs. Then it will gracefully crash and burn. Not to mention the widely unknown SELECT * view refresh problem that Tomas LaRock (@SQLRockstar on Twitter) and Colin Stasiuk (@BenchmarkIT on Twitter) talk about in detail. Go read about it, it’s informative. Refactoring this includes replacing the * with column names and most likely change to application using the database. Breaking apart huge stored procedures Have you ever seen seen a stored procedure that was 2000 lines long? I have. It’s not pretty. It hurts the eyes and sucks the will to live the next 10 minutes. They are a maintenance nightmare and turn into things no one dares to touch. I’m willing to bet that 100% of time they don’t have a single test on them. Large stored procedures (and functions) are a clear sign that they contain business logic. General opinion on good database coding practices says that business logic has no business in the database. That’s the applications part. Refactoring such behemoths requires writing lots of edge case tests for the stored procedure input/output behavior and then start to refactor it. First we split the logic inside into smaller parts like new stored procedures and UDFs. Those then get called from the master stored procedure. Once we’ve successfully modularized the database code it’s best to transfer that logic into the applications consuming it. This only leaves the stored procedure with common data manipulation logic. Of course this isn’t always possible so having a plethora of performance and behavior unit tests is absolutely necessary to confirm we’ve actually improved the codebase in some way.   Refactoring is not a popular chore amongst developers or managers. The former don’t like fixing old code, the latter can’t see the financial benefit. Remember how we talked about being lousy at estimating future costs in the previous post? But there comes a time when it must be done. Hopefully I’ve given you some ideas how to get started. In the last post of the series we’ll take a look at the tools to use and an example of testing and refactoring.

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  • How-to delete a tree node using the context menu

    - by frank.nimphius
    Hierarchical trees in Oracle ADF make use of View Accessors, which means that only the top level node needs to be exposed as a View Object instance on the ADF Business Components Data Model. This also means that only the top level node has a representation in the PageDef file as a tree binding and iterator binding reference. Detail nodes are accessed through tree rule definitions that use the accessor mentioned above (or nested collections in the case of POJO or EJB business services). The tree component is configured for single node selection, which however can be declaratively changed for users to press the ctrl key and selecting multiple nodes. In the following, I explain how to create a context menu on the tree for users to delete the selected tree nodes. For this, the context menu item will access a managed bean, which then determines the selected node(s), the internal ADF node bindings and the rows they represent. As mentioned, the ADF Business Components Data Model only needs to expose the top level node data sources, which in this example is an instance of the Locations View Object. For the tree to work, you need to have associations defined between entities, which usually is done for you by Oracle JDeveloper if the database tables have foreign keys defined Note: As a general hint of best practices and to simplify your life: Make sure your database schema is well defined and designed before starting your development project. Don't treat the database as something organic that grows and changes with the requirements as you proceed in your project. Business service refactoring in response to database changes is possible, but should be treated as an exception, not the rule. Good database design is a necessity – even for application developers – and nothing evil. To create the tree component, expand the Data Controls panel and drag the View Object collection to the view. From the context menu, select the tree component entry and continue with defining the tree rules that make up the hierarchical structure. As you see, when pressing the green plus icon  in the Edit Tree Binding  dialog, the data structure, Locations -  Departments – Employees in my sample, shows without you having created a View Object instance for each of the nodes in the ADF Business Components Data Model. After you configured the tree structure in the Edit Tree Binding dialog, you press OK and the tree is created. Select the tree in the page editor and open the Structure Window (ctrl+shift+S). In the Structure window, expand the tree node to access the conextMenu facet. Use the right mouse button to insert a Popup  into the facet. Repeat the same steps to insert a Menu and a Menu Item into the Popup you created. The Menu item text should be changed to something meaningful like "Delete". Note that the custom menu item later is added to the context menu together with the default context menu options like expand and expand all. To define the action that is executed when the menu item is clicked on, you select the Action Listener property in the Property Inspector and click the arrow icon followed by the Edit menu option. Create or select a managed bean and define a method name for the action handler. Next, select the tree component and browse to its binding property in the Property Inspector. Again, use the arrow icon | Edit option to create a component binding in the same managed bean that has the action listener defined. The tree handle is used in the action listener code, which is shown below: public void onTreeNodeDelete(ActionEvent actionEvent) {   //access the tree from the JSF component reference created   //using the af:tree "binding" property. The "binding" property   //creates a pair of set/get methods to access the RichTree instance   RichTree tree = this.getTreeHandler();   //get the list of selected row keys   RowKeySet rks = tree.getSelectedRowKeys();   //access the iterator to loop over selected nodes   Iterator rksIterator = rks.iterator();          //The CollectionModel represents the tree model and is   //accessed from the tree "value" property   CollectionModel model = (CollectionModel) tree.getValue();   //The CollectionModel is a wrapper for the ADF tree binding   //class, which is JUCtrlHierBinding   JUCtrlHierBinding treeBinding =                  (JUCtrlHierBinding) model.getWrappedData();          //loop over the selected nodes and delete the rows they   //represent   while(rksIterator.hasNext()){     List nodeKey = (List) rksIterator.next();     //find the ADF node binding using the node key     JUCtrlHierNodeBinding node =                       treeBinding.findNodeByKeyPath(nodeKey);     //delete the row.     Row rw = node.getRow();       rw.remove();   }          //only refresh the tree if tree nodes have been selected   if(rks.size() > 0){     AdfFacesContext adfFacesContext =                          AdfFacesContext.getCurrentInstance();     adfFacesContext.addPartialTarget(tree);   } } Note: To enable multi node selection for a tree, select the tree and change the row selection setting from "single" to "multiple". Note: a fully pictured version of this post will become available at the end of the month in a PDF summary on ADF Code Corner : http://www.oracle.com/technetwork/developer-tools/adf/learnmore/index-101235.html 

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  • Clarity is important, both in question and in answer.

    - by gerrylowry
    clarity is important ... i'm often reminded of the Clouseau movie in which Peter Sellers as Chief Inspector Clouseau asks a hotel clerk "Does your dog bite?" ... the clerk answers "no" ... after Clouseau has been bitten by the dog, he looks at the hotel clerk who says "That's not my dog".  Clarity is important, both in question and in answer. i've been a member of forums.asp.net since 2008 ... like many of my peers at forums.asp.net, i've answered my fair share of questions. FWIW, the purpose of this, my first web log post to http://weblogs.asp.net/gerrylowry is to help new members ask better questions and in turn get better answers. TIMTOWTDI  =.  there is more than one way to do it imho, the best way to ask a question in any forum, or even person to person, is to first formulate your question and then ask yourself to answer your own question. Things to consider when asking (the more complete your question, the more likely you'll get the answer you require): -- have you searched Google and/or your favourite search engine(s) before posting your question to forums.asp.net; examples: site:msdn.microsoft.com entity framework 5.0 c#http://lmgtfy.com/?q=site%3Amsdn.microsoft.com+entity+framework+5.0+c%23 site:forums.asp.net MVC tutorial c#http://lmgtfy.com/?q=site%3Aforums.asp.net+MVC+tutorial+c%23 -- are you asking your question in the correct forum?  look at the forums' descriptions at http://forums.asp.net/; examples: Getting Started If you have a general ASP.NET question on a topic that's not covered by one of the other more specific forums - ask it here. MVC Discussions regarding ASP.NET Model-View-Controller (MVC) C# Questions about using C# for ASP.NET development Note:  if your question pertains more to c# than to MVC, choosing the C# forum is likely to be more appropriate. -- is your post subject clear and concise, yet not too vague? compare these three subjects (all three had something to do with GridView):     (1)    please help     (2)    gridview      (3)    How to show newline in GridView  -- have you clearly explained your scenario? compare:  my leg hurts   with   when i walk too much, my right knee hurts in the knee joint  compare:  my code does not work    with    when i enter a date as 2012-11-8, i get a FormatException -- have you checked your spelling, your grammar, and your English? for better or worse, English is the language of forums.asp.net ... many of the currently 170000++ forums.asp.net are not native speakers of English; that's okay ... however, there are times when choosing the more appropriate words will likely get one a better answer; fortunately, there are web tools to help you formulate your question, for example, http://translate.google.com/.  -- have you provided relevant information about your environment? here are a few examples ... feel free to include other items to your question ... rule of thumb:  if you think a given detail is relevant, it likely is -- what technology are you using?    ASP.NET MVC 4, ASP.NET MVC 3, WebForms, ...  -- what version of Visual Studio are you using?  vs2012 (ultimate, professional, express), vs2010, vs2008 ... -- are you hosting your own website?  are you using a shared hosting service? -- are you experience difficulties in just one browser? more than one browser? -- what browser version(s) are you using?   ie8? ie9? ... -- what is your operating system?     win8, win7, vista, XP, server 2008 R2 ... -- what is your database?   SQL Server 2008 R2, ss2005, MySQL, Oracle, ... -- what is your web server?  iis 7.5, iis 6, .... -- have you provided enough information for someone to be able to answer your question? Here's an actual example from an O.P. that i hope is self-explanatory: I'm trying to make a simple calculator when i write the code in windows application it worked when i tried it in web application it doesn't work and there are no errors what should i do ??!! -- have you included unnecessary information? more than once, i've seen the O.P. (original post, original poster) include many extra lines of code that were not relevant to the actual question; the more unnecessary code that you include, the less likely your volunteer peers will be motivated to donate their time to help you. -- have you asked the question that you want answered? "Does this dog bite?" -- are your expectations reasonable? -- generally, persons who are going to answer your questions are your peers ... they are unpaid volunteers ... -- are you looking for help with your homework, work assignment, or hobby? or, are you expecting someone else to do your work for you?  -- do you expect a complete solution or are you simply looking for guidance and direction? -- you are likely to get more help by first making a reasonable effort to help yourself first Clarity is important, both in question and in answer. if you are answering someone else's question, please remember that clear answers are just as important as clear questions; would you understand your own answer? Things to consider when answering: -- have you tested your code example?  if you have, say so; if you've not tested your code example, also say so -- imho, it's okay to guess as long as you clearly state that you're guessing ... sometimes a wrong guess can still help the O.P. find her/his way to the right answer -- meanness does not contribute to being helpful; sometimes one may become frustrated with the O.P. and/or others participating in a thread, if that happens to you, be kind regardless; speaking from my own experience, at least once i've allowed myself to be frustrated into writing something inappropriate that i've regretted later ... being a meany does not feel good ... being kind and helpful feels fantastic! Tip:  before asking your question, read more than a few existing questions and answers to get a sense of how your peers ask and answer questions. Gerry P.S.:  try to avoid necroposting and piggy backing. necroposting is adding to an old post, especially one that was resolved months ago. piggy backing is adding your own question to someone else's thread.

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  • My First Weeks at Red Gate

    - by Jess Nickson
    Hi, my name’s Jess and early September 2012 I started working at Red Gate as a Software Engineer down in The Agency (the Publishing team). This was a bit of a shock, as I didn’t think this team would have any developers! I admit, I was a little worried when it was mentioned that my role was going to be different from normal dev. roles within the company. However, as luck would have it, I was placed within a team that was responsible for the development and maintenance of Simple-Talk and SQL Server Central (SSC). I felt rather unprepared for this role. I hadn’t used many of the technologies involved and of those that I had, I hadn’t looked at them for quite a while. I was, nevertheless, quite excited about this turn of events. As I had predicted, the role has been quite challenging so far. I expected that I would struggle to get my head round the large codebase already in place, having never used anything so much as a fraction of the size of this before. However, I was perhaps a bit naive when it came to how quickly things would move. I was required to start learning/remembering a number of different languages and technologies within time frames I would never have tried to set myself previously. Having said that, my first week was pretty easy. It was filled with meetings that were designed to get the new starters up to speed with the different departments, ideals and rules within the company. I also attended some lightning talks being presented by other employees, which were pretty useful. These occur once a fortnight and normally consist of around four speakers. In my spare time, we set up the Simple-Talk codebase on my computer and I started exploring it and worked on my first feature – redirecting requests for URLs that used incorrect casing! It was also during this time that I was given my first introduction to test-driven development (TDD) with Michael via a code kata. Although I had heard of the general ideas behind TDD, I had definitely never tried it before. Indeed, I hadn’t really done any automated testing of code before, either. The session was therefore very useful and gave me insights as to some of the coding practices used in my team. Although I now understand the importance of TDD, it still seems odd in my head and I’ve yet to master how to sensibly step up the functionality of the code a bit at a time. The second week was both easier and more difficult than the first. I was given a new project to work on, meaning I was no longer using the codebase already in place. My job was to take some designs, a WordPress theme, and some initial content and build a page that allowed users of the site to read provided resources and give feedback. This feedback could include their thoughts about the resource, the topics covered and the page design itself. Although it didn’t sound the most challenging of projects when compared to fixing bugs in our current codebase, it nevertheless provided a few sneaky problems that had me stumped. I really enjoyed working on this project as it allowed me to play around with HTML, CSS and JavaScript; all things that I like working with but rarely have a chance to use. I completed the aims for the project on time and was happy with the final outcome – though it still needs a good designer to take a look at it! I am now into my third week at Red Gate and I have temporarily been pulled off the website from week 2. I am again back to figuring out the Simple-Talk codebase. Monday provided me with the chance to learn a bunch of new things: system level testing, Selenium and Python. I was set the challenge of testing a bug fix dealing with the search bars in Simple-Talk. The exercise was pretty fun, although Mike did have to point me in the right direction when I started making the tests a bit too complex. The rest of the week looks set to be focussed on pair programming with Mike as we work together on a new feature. I look forward to the challenges that still face me and hope that I will be able to get up to speed quickly. *fingers crossed*

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  • SSIS: Building SQL databases on-the-fly using concatenated SQL scripts

    - by DrJohn
    Over the years I have developed many techniques which help automate the whole SQL Server build process. In my current process, where I need to build entire OLAP data marts on-the-fly, I make regular use of a simple but very effective mechanism to concatenate all the SQL Scripts together from my SSMS (SQL Server Management Studio) projects. This proves invaluable because in two clicks I can redeploy an entire SQL Server database with all tables, views, stored procedures etc. Indeed, I can also use the concatenated SQL scripts with SSIS to build SQL Server databases on-the-fly. You may be surprised to learn that I often redeploy the database several times per day, or even several times per hour, during the development process. This is because the deployment errors are logged and you can quickly see where SQL Scripts have object dependency errors. For example, after changing a table structure you may have forgotten to change any related views. The deployment log immediately points out all the objects which failed to build so you can fix and redeploy the database very quickly. The alternative approach (i.e. doing changes in the database directly using the SSMS UI) would require you to check all dependent objects before making changes. The chances are that you will miss something and wonder why your app returns the wrong data – a common problem caused by changing a table without re-creating dependent views. Using SQL Projects in SSMS A great many developers fail to make use of SQL Projects in SSMS (SQL Server Management Studio). To me they are invaluable way of organizing your SQL Scripts. The screenshot below shows a typical SSMS solution made up of several projects – one project for tables, another for views etc. The key point is that the projects naturally fall into the right order in file system because of the project name. The number in the folder or file name ensures that the projects the SQL scripts are concatenated together in the order that they need to be executed. Hence the script filenames start with 100, 110 etc. Concatenating SQL Scripts To concatenate the SQL Scripts together into one file, I use notepad.exe to create a simple batch file (see example screenshot) which uses the TYPE command to write the content of the SQL Script files into a combined file. As the SQL Scripts are in several folders, I simply use several TYPE command multiple times and append the output together. If you are unfamiliar with batch files, you may not know that the angled bracket (>) means write output of the program into a file. Two angled brackets (>>) means append output of this program into a file. So the command-line DIR > filelist.txt would write the content of the DIR command into a file called filelist.txt. In the example shown above, the concatenated file is called SB_DDS.sql If, like me you place the concatenated file under source code control, then the source code control system will change the file's attribute to "read-only" which in turn would cause the TYPE command to fail. The ATTRIB command can be used to remove the read-only flag. Using SQLCmd to execute the concatenated file Now that the SQL Scripts are all in one big file, we can execute the script against a database using SQLCmd using another batch file as shown below: SQLCmd has numerous options, but the script shown above simply executes the SS_DDS.sql file against the SB_DDS_DB database on the local machine and logs the errors to a file called SB_DDS.log. So after executing the batch file you can simply check the error log to see if your database built without a hitch. If you have errors, then simply fix the source files, re-create the concatenated file and re-run the SQLCmd to rebuild the database. This two click operation allows you to quickly identify and fix errors in your entire database definition.Using SSIS to execute the concatenated file To execute the concatenated SQL script using SSIS, you simply drop an Execute SQL task into your package and set the database connection as normal and then select File Connection as the SQLSourceType (as shown below). Create a file connection to your concatenated SQL script and you are ready to go.   Tips and TricksAdd a new-line at end of every fileThe most common problem encountered with this approach is that the GO statement on the last line of one file is placed on the same line as the comment at the top of the next file by the TYPE command. The easy fix to this is to ensure all your files have a new-line at the end.Remove all USE database statementsThe SQLCmd identifies which database the script should be run against.  So you should remove all USE database commands from your scripts - otherwise you may get unintentional side effects!!Do the Create Database separatelyIf you are using SSIS to create the database as well as create the objects and populate the database, then invoke the CREATE DATABASE command against the master database using a separate package before calling the package that executes the concatenated SQL script.    

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  • Day 3 - XNA: Hacking around with images

    - by dapostolov
    Yay! Today I'm going to get into some code! My mind has been on this all day! I find it amusing how I practice, daily, to be "in the moment" or "present" and the excitement and anticipation of this project seems to snatch it away from me frequently. WELL!!! (Shakes Excitedly) Let's do this =)! Let's code! For these next few days it is my intention to better understand image rendering using XNA; after said prototypes are complete I should (fingers crossed) be able to dive into my game code using the design document I hammered out the other night. On a personal note, I think the toughest thing right now is finding the time to do this project. Each night, after my little ones go to bed I can only really afford a couple hours of work on this project. However, I hope to utilise this time as best as I can because this is the first time in a while I've found a project that I've been passionate about. A friend recently asked me if I intend to go 3D or extend the game design. Yes. For now I'm keeping it simple. Lastly, just as a note, as I was doing some further research into image rendering this morning I came across some other XNA content and lessons learned. I believe this content could have probably been posted in the first couple of posts, however, I will share the new content as I learn it at the end of each day. Maybe I'll take some time later to fix the posts but for now Installation and Deployment - Lessons Learned I had installed the XNA studio  (Day 1) and the site instructions were pretty easy to follow. However, I had a small difficulty with my development environment. You see, I run a virtual desktop development environment. Even though I was able to code and compile all the tutorials the game failed to run...because I lacked a 3D capable card; it was not detected on the virtual box... First Lesson: The XNA runtime needs to "see" the 3D card! No sweat, Il copied the files over to my parent box and executed the program. ERROR. Hmm... Second Lesson (which I should have probably known but I let the excitement get the better of me): you need the XNA runtime on the client PC to run the game, oh, and don't forget the .Net Runtime! Sprite, it ain't just a Soft Drink... With these prototypes I intend to understand and perform the following tasks. learn game development terminology how to place and position (rotate) a static image on the screen how to layer static images on the screen understand image scaling can we reuse images? understand how framerate is handled in XNA how to display text , basic shapes, and colors on the screen how to interact with an image (collision of user input?) how to animate an image and understand basic animation techniques how to detect colliding images or screen edges how to manipulate the image, lets say colors, stretching how to focus on a segment of an image...like only displaying a frame on a film reel what's the best way to manage images (compression, storage, location, prevent artwork theft, etc.) Well, let's start with this "prototype" task list for now...Today, let's get an image on the screen and maybe I can mark a few of the tasks as completed... C# Prototype1 New Visual Studio Project Select the XNA Game Studio 3.1 Project Type Select the Windows Game 3.1 Template Type Prototype1 in the Name textbox provided Press OK. At this point code has auto-magically been created. Feel free to press the F5 key to run your first XNA program. You should have a blue screen infront of you. Without getting into the nitty gritty right, the code that was generated basically creates some basic code to clear the window content with the lovely CornFlowerBlue color. Something to notice, when you move your mouse into the window...nothing. ooooo spoooky. Let's put an image on that screen! Step A - Get an Image into the solution Under "Content" in your Solution Explorer, right click and add a new folder and name it "Sprites". Copy a small image in there; I copied a "Royalty Free" wizard hat from a quick google search and named it wizards_hat.jpg (rightfully so!) Step B - Add the sprite and position fields Now, open/edit  Game1.cs Locate the following line:  SpriteBatch spriteBatch; Under this line type the following:         SpriteBatch spriteBatch; // the line you are looking for...         Texture2D sprite;         Vector2 position; Step C - Load the image asset Locate the "Load Content" Method and duplicate the following:             protected override void LoadContent()         {             spriteBatch = new SpriteBatch(GraphicsDevice);             // your image name goes here...             sprite = Content.Load<Texture2D>("Sprites\\wizards_hat");             position = new Vector2(200, 100);             base.LoadContent();         } Step D - Draw the image Locate the "Draw" Method and duplicate the following:        protected override void Draw(GameTime gameTime)         {             GraphicsDevice.Clear(Color.CornflowerBlue);             spriteBatch.Begin(SpriteBlendMode.AlphaBlend);             spriteBatch.Draw(sprite, position, Color.White);             spriteBatch.End();             base.Draw(gameTime);         }  Step E - Compile and Run Engage! (F5) - Debug! Your image should now display on a cornflowerblue window about 200 pixels from the left and 100 pixels from the top. Awesome! =) Pretty cool how we only coded a few lines to display an image, but believe me, there is plenty going on behind the scenes. However, for now, I'm going to call it a night here. Blogging all this progress certainly takes time... However, tomorrow night I'm going to detail what we just did, plus start checking off points on that list! I'm wondering right now if I should add pictures / code to this post...let me know if you want them =) Best Regards, D.

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  • SQL SERVER – Curious Case of Disappearing Rows – ON UPDATE CASCADE and ON DELETE CASCADE – Part 1 of 2

    - by pinaldave
    Social media has created an Always Connected World for us. Recently I enrolled myself to learn new technologies as a student. I had decided to focus on learning and decided not to stay connected on the internet while I am in the learning session. On the second day of the event after the learning was over, I noticed lots of notification from my friend on my various social media handle. He had connected with me on Twitter, Facebook, Google+, LinkedIn, YouTube as well SMS, WhatsApp on the phone, Skype messages and not to forget with a few emails. I right away called him up. The problem was very unique – let us hear the problem in his own words. “Pinal – we are in big trouble we are not able to figure out what is going on. Our product details table is continuously loosing rows. Lots of rows have disappeared since morning and we are unable to find why the rows are getting deleted. We have made sure that there is no DELETE command executed on the table as well. The matter of the fact, we have removed every single place the code which is referencing the table. We have done so many crazy things out of desperation but no luck. The rows are continuously deleted in a random pattern. Do you think we have problems with intrusion or virus?” After describing the problems he had pasted few rants about why I was not available during the day. I think it will be not smart to post those exact words here (due to many reasons). Well, my immediate reaction was to get online with him. His problem was unique to him and his team was all out to fix the issue since morning. As he said he has done quite a lot out in desperation. I started asking questions from audit, policy management and profiling the data. Very soon I realize that I think this problem was not as advanced as it looked. There was no intrusion, SQL Injection or virus issue. Well, long story short first - It was a very simple issue of foreign key created with ON UPDATE CASCADE and ON DELETE CASCADE.  CASCADE allows deletions or updates of key values to cascade through the tables defined to have foreign key relationships that can be traced back to the table on which the modification is performed. ON DELETE CASCADE specifies that if an attempt is made to delete a row with a key referenced by foreign keys in existing rows in other tables, all rows containing those foreign keys are also deleted. ON UPDATE CASCADE specifies that if an attempt is made to update a key value in a row, where the key value is referenced by foreign keys in existing rows in other tables, all of the foreign key values are also updated to the new value specified for the key. (Reference: BOL) In simple words – due to ON DELETE CASCASE whenever is specified when the data from Table A is deleted and if it is referenced in another table using foreign key it will be deleted as well. In my friend’s case, they had two tables, Products and ProductDetails. They had created foreign key referential integrity of the product id between the table. Now the as fall was up they were updating their catalogue. When they were updating the catalogue they were deleting products which are no more available. As the changes were cascading the corresponding rows were also deleted from another table. This is CORRECT. The matter of the fact, there is no error or anything and SQL Server is behaving how it should be behaving. The problem was in the understanding and inappropriate implementations of business logic.  What they needed was Product Master Table, Current Product Catalogue, and Product Order Details History tables. However, they were using only two tables and without proper understanding the relation between them was build using foreign keys. If there were only two table, they should have used soft delete which will not actually delete the record but just hide it from the original product table. This workaround could have got them saved from cascading delete issues. I will be writing a detailed post on the design implications etc in my future post as in above three lines I cannot cover every issue related to designing and it is also not the scope of the blog post. More about designing in future blog posts. Once they learn their mistake, they were happy as there was no intrusion but trust me sometime we are our own enemy and this is a great example of it. In tomorrow’s blog post we will go over their code and workarounds. Feel free to share your opinions, experiences and comments. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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