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• Michael Crump&rsquo;s notes for 70-563 PRO &ndash; Designing and Developing Windows Applications usi

  - by mbcrump

  TIME TO GO PRO! This is my notes for 70-563 PRO – Designing and Developing Windows Applications using .NET Framework 3.5 I created it using several resources (various certification web sites, msdn, official ms 70-548 book). The reason that I created this review is because a) I am taking the exam. b) MS did not create a book for this exam. Use the(MS 70-548)book. c) To make sure I am familiar with each before the exam. I hope that it provides a good start for your own notes. I hope that someone finds this useful. At least, it will give you a starting point of what to expect to know on the PRO exam. Also, for those wondering, the PRO exam does contains very little code. It is basically all theory. 1. Validation Controls – How to prevent users from entering invalid data on forms. (MaskedTextBox control and RegEx) 2. ServiceController – used to start and control the behavior of existing services. 3. User Feedback (know winforms Status Bar, Tool Tips, Color, Error Provider, Context-Sensitive and Accessibility) 4. Specific (derived) exceptions must be handled before general (base class) exceptions. By moving the exception handling for the base type Exception to after exception handling of ArgumentNullException, all ArgumentNullException thrown by the Helper method will be caught and logged correctly. 5. A heartbeat method is a method exposed by a Web service that allows external applications to check on the status of the service. 6. New users must master key tasks quickly. Giving these tasks context and appropriate detail will help. However, advanced users will demand quicker paths. Shortcuts, accelerators, or toolbar buttons will speed things along for the advanced user. 7. MSBuild uses project files to instruct the build engine what to build and how to build it. MSBuild project files are XML files that adhere to the MSBuild XML schema. The MSBuild project files contain complete file, build action, and dependency information for each individual projects. 8. Evaluating whether or not to fix a bug involves a triage process. You must identify the bug's impact, set the priority, categorize it, and assign a developer. Many times the person doing the triage work will assign the bug to a developer for further investigation. In fact, the workflow for the bug work item inside of Team System supports this step. Developers are often asked to assess the impact of a given bug. This assessment helps the person doing the triage make a decision on how to proceed. When assessing the impact of a bug, you should consider time and resources to fix it, bug risk, and impacts of the bug. 9. In large projects it is generally impossible and unfeasible to fix all bugs because of the impact on schedule and budget. 10. Code reviews should be conducted by a technical lead or a technical peer. 11. Testing Applications 12. WCF Services – application state 13. SQL Server 2005 / 2008 Express Edition – reliable storage of data / Microsoft SQL Server 3.5 Compact Database– used for client computers to retrieve and save data from a shared location. 14. SQL Server 2008 Compact Edition – used for minimum possible memory and can synchronize data with a corporate SQL Server 2008 Database. Supports offline user and minimum dependency on external components. 15. MDI and SDI Forms (specifically IsMDIContainer) 16. GUID – in the case of data warehousing, it is important to define unique keys. 17. Encrypting / Security Data 18. Understanding of Isolated Storage/Proper location to store items 19. LINQ to SQL 20. Multithreaded access 21. ADO.NET Entity Framework model 22. Marshal.ReleaseComObject 23. Common User Interface Layout (ComboBox, ListBox, Listview, MaskedTextBox, TextBox, RichTextBox, SplitContainer, TableLayoutPanel, TabControl) 24. DataSets Class - http://msdn.microsoft.com/en-us/library/system.data.dataset%28VS.71%29.aspx 25. SQL Server 2008 Reporting Services (SSRS) 26. SystemIcons.Shield (Vista UAC) 27. Leverging stored procedures to perform data manipulation for a database schema that can change. 28. DataContext 29. Microsoft Windows Installer Packages, ClickOnce(bootstrapping features), XCopy. 30. Client Application Services – will authenticate users by using the same data source as a ASP.NET web application. 31. SQL Server 2008 Caching 32. StringBuilder 33. Accessibility Guidelines for Windows Applications http://msdn.microsoft.com/en-us/library/ms228004.aspx 34. Logging erros 35. Testing performance related issues. 36. Role Based Security, GenericIdentity and GenericPrincipal 37. System.Net.CookieContainer will store session data for webapps (see isolated storage for winforms) 38. .NET CLR Profiler tool will identify objects that cause performance issues. 39. ADO.NET Synchronization (SyncGroup) 40. Globalization - CultureInfo 41. IDisposable Interface- reports on several questions relating to this. 42. Adding timestamps to determine whether data has changed or not. 43. Converting applications to .NET Framework 3.5 44. MicrosoftReportViewer 45. Composite Controls 46. Windows Vista KNOWN folders. 47. Microsoft Sync Framework 48. TypeConverter -Provides a unified way of converting types of values to other types, as well as for accessing standard values and sub properties. http://msdn.microsoft.com/en-us/library/system.componentmodel.typeconverter.aspx 49. Concurrency control mechanisms The main categories of concurrency control mechanisms are: Optimistic - Delay the checking of whether a transaction meets the isolation rules (e.g., serializability and recoverability) until its end, without blocking any of its (read, write) operations, and then abort a transaction, if the desired rules are violated. Pessimistic - Block operations of a transaction, if they may cause violation of the rules. Semi-optimistic - Block operations in some situations, and do not block in other situations, while delaying rules checking to transaction's end, as done with optimistic. 50. AutoResetEvent 51. Microsoft Messaging Queue (MSMQ) 4.0 52. Bulk imports 53. KeyDown event of controls 54. WPF UI components 55. UI process layer 56. GAC (installing, removing and queuing) 57. Use a local database cache to reduce the network bandwidth used by applications. 58. Sound can easily be annoying and distracting to users, so use it judiciously. Always give users the option to turn sound off. Because a user might have sound off, never convey important information through sound alone.

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• ODI 12c - Parallel Table Load

  - by David Allan

  In this post we will look at the ODI 12c capability of parallel table load from the aspect of the mapping developer and the knowledge module developer - two quite different viewpoints. This is about parallel table loading which isn't to be confused with loading multiple targets per se. It supports the ability for ODI mappings to be executed concurrently especially if there is an overlap of the datastores that they access, so any temporary resources created may be uniquely constructed by ODI. Temporary objects can be anything basically - common examples are staging tables, indexes, views, directories - anything in the ETL to help the data integration flow do its job. In ODI 11g users found a few workarounds (such as changing the technology prefixes - see here) to build unique temporary names but it was more of a challenge in error cases. ODI 12c mappings by default operate exactly as they did in ODI 11g with respect to these temporary names (this is also true for upgraded interfaces and scenarios) but can be configured to support the uniqueness capabilities. We will look at this feature from two aspects; that of a mapping developer and that of a developer (of procedures or KMs). 1. Firstly as a Mapping Developer..... 1.1 Control when uniqueness is enabled A new property is available to set unique name generation on/off. When unique names have been enabled for a mapping, all temporary names used by the collection and integration objects will be generated using unique names. This property is presented as a check-box in the Property Inspector for a deployment specification. 1.2 Handle cleanup after successful execution Provided that all temporary objects that are created have a corresponding drop statement then all of the temporary objects should be removed during a successful execution. This should be the case with the KMs developed by Oracle. 1.3 Handle cleanup after unsuccessful execution If an execution failed in ODI 11g then temporary tables would have been left around and cleaned up in the subsequent run. In ODI 12c, KM tasks can now have a cleanup-type task which is executed even after a failure in the main tasks. These cleanup tasks will be executed even on failure if the property 'Remove Temporary Objects on Error' is set. If the agent was to crash and not be able to execute this task, then there is an ODI tool (OdiRemoveTemporaryObjects here) you can invoke to cleanup the tables - it supports date ranges and the like. That's all there is to it from the aspect of the mapping developer it's much, much simpler and straightforward. You can now execute the same mapping concurrently or execute many mappings using the same resource concurrently without worrying about conflict.  2. Secondly as a Procedure or KM Developer..... In the ODI Operator the executed code shows the actual name that is generated - you can also see the runtime code prior to execution (introduced in 11.1.1.7), for example below in the code type I selected 'Pre-executed Code' this lets you see the code about to be processed and you can also see the executed code (which is the default view). References to the collection (C$) and integration (I$) names will be automatically made unique by using the odiRef APIs - these objects will have unique names whenever concurrency has been enabled for a particular mapping deployment specification. It's also possible to use name uniqueness functions in procedures and your own KMs. 2.1 New uniqueness tags  You can also make your own temporary objects have unique names by explicitly including either %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG in the name passed to calls to the odiRef APIs. Such names would always include the unique tag regardless of the concurrency setting. To illustrate, let's look at the getObjectName() method. At <% expansion time, this API will append %UNIQUE_STEP_TAG to the object name for collection and integration tables. The name parameter passed to this API may contain  %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG. This API always generates to the <? version of getObjectName() At execution time this API will replace the unique tag macros with a string that is unique to the current execution scope. The returned name will conform to the name-length restriction for the target technology, and its pattern for the unique tag. Any necessary truncation will be performed against the initial name for the object and any other fixed text that may have been specified. Examples are:- <?=odiRef.getObjectName("L", "%COL_PRFEMP%UNIQUE_STEP_TAG", "D")?> SCOTT.C$_EABH7QI1BR1EQI3M76PG9SIMBQQ <?=odiRef.getObjectName("L", "EMP%UNIQUE_STEP_TAG_AE", "D")?> SCOTT.EMPAO96Q2JEKO0FTHQP77TMSAIOSR_ Methods which have this kind of support include getFrom, getTableName, getTable, getObjectShortName and getTemporaryIndex. There are APIs for retrieving this tag info also, the getInfo API has been extended with the following properties (the UNIQUE* properties can also be used in ODI procedures); UNIQUE_STEP_TAG - Returns the unique value for the current step scope, e.g. 5rvmd8hOIy7OU2o1FhsF61 Note that this will be a different value for each loop-iteration when the step is in a loop. UNIQUE_SESSION_TAG - Returns the unique value for the current session scope, e.g. 6N38vXLrgjwUwT5MseHHY9 IS_CONCURRENT - Returns info about the current mapping, will return 0 or 1 (only in % phase) GUID_SRC_SET - Returns the UUID for the current source set/execution unit (only in % phase) The getPop API has been extended with the IS_CONCURRENT property which returns info about an mapping, will return 0 or 1.  2.2 Additional APIs Some new APIs are provided including getFormattedName which will allow KM developers to construct a name from fixed-text or ODI symbols that can be optionally truncate to a max length and use a specific encoding for the unique tag. It has syntax getFormattedName(String pName[, String pTechnologyCode]) This API is available at both the % and the ? phase.  The format string can contain the ODI prefixes that are available for getObjectName(), e.g. %INT_PRF, %COL_PRF, %ERR_PRF, %IDX_PRF alongwith %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG. The latter tags will be expanded into a unique string according to the specified technology. Calls to this API within the same execution context are guaranteed to return the same unique name provided that the same parameters are passed to the call. e.g. <%=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG_AE", "ORACLE")%> <?=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG_AE", "ORACLE")?> C$_MY_TAB7wDiBe80vBog1auacS1xB_AE <?=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG.log", "FILE")?> C2_MY_TAB7wDiBe80vBog1auacS1xB.log 2.3 Name length generation  As part of name generation, the length of the generated name will be compared with the maximum length for the target technology and truncation may need to be applied. When a unique tag is included in the generated string it is important that uniqueness is not compromised by truncation of the unique tag. When a unique tag is NOT part of the generated name, the name will be truncated by removing characters from the end - this is the existing 11g algorithm. When a unique tag is included, the algorithm will first truncate the <postfix> and if necessary  the <prefix>. It is recommended that users will ensure there is sufficient uniqueness in the <prefix> section to ensure uniqueness of the final resultant name. SUMMARY To summarize, ODI 12c make it much simpler to utilize mappings in concurrent cases and provides APIs for helping developing any procedures or custom knowledge modules in such a way they can be used in highly concurrent, parallel scenarios. 

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• SQL SERVER – Introduction to SQL Server 2014 In-Memory OLTP

  - by Pinal Dave

  In SQL Server 2014 Microsoft has introduced a new database engine component called In-Memory OLTP aka project “Hekaton” which is fully integrated into the SQL Server Database Engine. It is optimized for OLTP workloads accessing memory resident data. In-memory OLTP helps us create memory optimized tables which in turn offer significant performance improvement for our typical OLTP workload. The main objective of memory optimized table is to ensure that highly transactional tables could live in memory and remain in memory forever without even losing out a single record. The most significant part is that it still supports majority of our Transact-SQL statement. Transact-SQL stored procedures can be compiled to machine code for further performance improvements on memory-optimized tables. This engine is designed to ensure higher concurrency and minimal blocking. In-Memory OLTP alleviates the issue of locking, using a new type of multi-version optimistic concurrency control. It also substantially reduces waiting for log writes by generating far less log data and needing fewer log writes. Points to remember Memory-optimized tables refer to tables using the new data structures and key words added as part of In-Memory OLTP. Disk-based tables refer to your normal tables which we used to create in SQL Server since its inception. These tables use a fixed size 8 KB pages that need to be read from and written to disk as a unit. Natively compiled stored procedures refer to an object Type which is new and is supported by in-memory OLTP engine which convert it into machine code, which can further improve the data access performance for memory –optimized tables. Natively compiled stored procedures can only reference memory-optimized tables, they can’t be used to reference any disk –based table. Interpreted Transact-SQL stored procedures, which is what SQL Server has always used. Cross-container transactions refer to transactions that reference both memory-optimized tables and disk-based tables. Interop refers to interpreted Transact-SQL that references memory-optimized tables. Using In-Memory OLTP In-Memory OLTP engine has been available as part of SQL Server 2014 since June 2013 CTPs. Installation of In-Memory OLTP is part of the SQL Server setup application. The In-Memory OLTP components can only be installed with a 64-bit edition of SQL Server 2014 hence they are not available with 32-bit editions. Creating Databases Any database that will store memory-optimized tables must have a MEMORY_OPTIMIZED_DATA filegroup. This filegroup is specifically designed to store the checkpoint files needed by SQL Server to recover the memory-optimized tables, and although the syntax for creating the filegroup is almost the same as for creating a regular filestream filegroup, it must also specify the option CONTAINS MEMORY_OPTIMIZED_DATA. Here is an example of a CREATE DATABASE statement for a database that can support memory-optimized tables: CREATE DATABASE InMemoryDB ON PRIMARY(NAME = [InMemoryDB_data], FILENAME = 'D:\data\InMemoryDB_data.mdf', size=500MB), FILEGROUP [SampleDB_mod_fg] CONTAINS MEMORY_OPTIMIZED_DATA (NAME = [InMemoryDB_mod_dir], FILENAME = 'S:\data\InMemoryDB_mod_dir'), (NAME = [InMemoryDB_mod_dir], FILENAME = 'R:\data\InMemoryDB_mod_dir') LOG ON (name = [SampleDB_log], Filename='L:\log\InMemoryDB_log.ldf', size=500MB) COLLATE Latin1_General_100_BIN2; Above example code creates files on three different drives (D:  S: and R:) for the data files and in memory storage so if you would like to run this code kindly change the drive and folder locations as per your convenience. Also notice that binary collation was specified as Windows (non-SQL). BIN2 collation is the only collation support at this point for any indexes on memory optimized tables. It is also possible to add a MEMORY_OPTIMIZED_DATA file group to an existing database, use the below command to achieve the same. ALTER DATABASE AdventureWorks2012 ADD FILEGROUP hekaton_mod CONTAINS MEMORY_OPTIMIZED_DATA; GO ALTER DATABASE AdventureWorks2012 ADD FILE (NAME='hekaton_mod', FILENAME='S:\data\hekaton_mod') TO FILEGROUP hekaton_mod; GO Creating Tables There is no major syntactical difference between creating a disk based table or a memory –optimized table but yes there are a few restrictions and a few new essential extensions. Essentially any memory-optimized table should use the MEMORY_OPTIMIZED = ON clause as shown in the Create Table query example. DURABILITY clause (SCHEMA_AND_DATA or SCHEMA_ONLY) Memory-optimized table should always be defined with a DURABILITY value which can be either SCHEMA_AND_DATA or  SCHEMA_ONLY the former being the default. A memory-optimized table defined with DURABILITY=SCHEMA_ONLY will not persist the data to disk which means the data durability is compromised whereas DURABILITY= SCHEMA_AND_DATA ensures that data is also persisted along with the schema. Indexing Memory Optimized Table A memory-optimized table must always have an index for all tables created with DURABILITY= SCHEMA_AND_DATA and this can be achieved by declaring a PRIMARY KEY Constraint at the time of creating a table. The following example shows a PRIMARY KEY index created as a HASH index, for which a bucket count must also be specified. CREATE TABLE Mem_Table ( [Name] VARCHAR(32) NOT NULL PRIMARY KEY NONCLUSTERED HASH WITH (BUCKET_COUNT = 100000), [City] VARCHAR(32) NULL, [State_Province] VARCHAR(32) NULL, [LastModified] DATETIME NOT NULL, ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA); Now as you can see in the above query example we have used the clause MEMORY_OPTIMIZED = ON to make sure that it is considered as a memory optimized table and not just a normal table and also used the DURABILITY Clause= SCHEMA_AND_DATA which means it will persist data along with metadata and also you can notice this table has a PRIMARY KEY mentioned upfront which is also a mandatory clause for memory-optimized tables. We will talk more about HASH Indexes and BUCKET_COUNT in later articles on this topic which will be focusing more on Row and Index storage on Memory-Optimized tables. So stay tuned for that as well. Now as we covered the basics of Memory Optimized tables and understood the key things to remember while using memory optimized tables, let’s explore more using examples to understand the Performance gains using memory-optimized tables. I will be using the database which i created earlier in this article i.e. InMemoryDB in the below Demo Exercise. USE InMemoryDB GO -- Creating a disk based table CREATE TABLE dbo.Disktable ( Id INT IDENTITY, Name CHAR(40) ) GO CREATE NONCLUSTERED INDEX IX_ID ON dbo.Disktable (Id) GO -- Creating a memory optimized table with similar structure and DURABILITY = SCHEMA_AND_DATA CREATE TABLE dbo.Memorytable_durable ( Id INT NOT NULL PRIMARY KEY NONCLUSTERED Hash WITH (bucket_count =1000000), Name CHAR(40) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA) GO -- Creating an another memory optimized table with similar structure but DURABILITY = SCHEMA_Only CREATE TABLE dbo.Memorytable_nondurable ( Id INT NOT NULL PRIMARY KEY NONCLUSTERED Hash WITH (bucket_count =1000000), Name CHAR(40) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_only) GO -- Now insert 100000 records in dbo.Disktable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Disktable(Name) VALUES('sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END -- Do the same inserts for Memory table dbo.Memorytable_durable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Memorytable_durable VALUES(@i_t, 'sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END -- Now finally do the same inserts for Memory table dbo.Memorytable_nondurable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Memorytable_nondurable VALUES(@i_t, 'sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END The above 3 Inserts took 1.20 minutes, 54 secs, and 2 secs respectively to insert 100000 records on my machine with 8 Gb RAM. This proves the point that memory-optimized tables can definitely help businesses achieve better performance for their highly transactional business table and memory- optimized tables with Durability SCHEMA_ONLY is even faster as it does not bother persisting its data to disk which makes it supremely fast. Koenig Solutions is one of the few organizations which offer IT training on SQL Server 2014 and all its updates. Now, I leave the decision on using memory_Optimized tables on you, I hope you like this article and it helped you understand  the fundamentals of IN-Memory OLTP . Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Koenig

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• Security in Software

  The term security has many meanings based on the context and perspective in which it is used. Security from the perspective of software/system development is the continuous process of maintaining confidentiality, integrity, and availability of a system, sub-system, and system data. This definition at a very high level can be restated as the following: Computer security is a continuous process dealing with confidentiality, integrity, and availability on multiple layers of a system. Key Aspects of Software Security Integrity Confidentiality Availability Integrity within a system is the concept of ensuring only authorized users can only manipulate information through authorized methods and procedures. An example of this can be seen in a simple lead management application.  If the business decided to allow each sales member to only update their own leads in the system and sales managers can update all leads in the system then an integrity violation would occur if a sales member attempted to update someone else’s leads. An integrity violation occurs when a team member attempts to update someone else’s lead because it was not entered by the sales member.  This violates the business rule that leads can only be update by the originating sales member. Confidentiality within a system is the concept of preventing unauthorized access to specific information or tools.  In a perfect world the knowledge of the existence of confidential information/tools would be unknown to all those who do not have access. When this this concept is applied within the context of an application only the authorized information/tools will be available. If we look at the sales lead management system again, leads can only be updated by originating sales members. If we look at this rule then we can say that all sales leads are confidential between the system and the sales person who entered the lead in to the system. The other sales team members would not need to know about the leads let alone need to access it. Availability within a system is the concept of authorized users being able to access the system. A real world example can be seen again from the lead management system. If that system was hosted on a web server then IP restriction can be put in place to limit access to the system based on the requesting IP address. If in this example all of the sales members where accessing the system from the 192.168.1.23 IP address then removing access from all other IPs would be need to ensure that improper access to the system is prevented while approved users can access the system from an authorized location. In essence if the requesting user is not coming from an authorized IP address then the system will appear unavailable to them. This is one way of controlling where a system is accessed. Through the years several design principles have been identified as being beneficial when integrating security aspects into a system. These principles in various combinations allow for a system to achieve the previously defined aspects of security based on generic architectural models. Security Design Principles Least Privilege Fail-Safe Defaults Economy of Mechanism Complete Mediation Open Design Separation Privilege Least Common Mechanism Psychological Acceptability Defense in Depth Least Privilege Design PrincipleThe Least Privilege design principle requires a minimalistic approach to granting user access rights to specific information and tools. Additionally, access rights should be time based as to limit resources access bound to the time needed to complete necessary tasks. The implications of granting access beyond this scope will allow for unnecessary access and the potential for data to be updated out of the approved context. The assigning of access rights will limit system damaging attacks from users whether they are intentional or not. This principle attempts to limit data changes and prevents potential damage from occurring by accident or error by reducing the amount of potential interactions with a resource. Fail-Safe Defaults Design PrincipleThe Fail-Safe Defaults design principle pertains to allowing access to resources based on granted access over access exclusion. This principle is a methodology for allowing resources to be accessed only if explicit access is granted to a user. By default users do not have access to any resources until access has been granted. This approach prevents unauthorized users from gaining access to resource until access is given. Economy of Mechanism Design PrincipleThe Economy of mechanism design principle requires that systems should be designed as simple and small as possible. Design and implementation errors result in unauthorized access to resources that would not be noticed during normal use. Complete Mediation Design PrincipleThe Complete Mediation design principle states that every access to every resource must be validated for authorization. Open Design Design PrincipleThe Open Design Design Principle is a concept that the security of a system and its algorithms should not be dependent on secrecy of its design or implementation Separation Privilege Design PrincipleThe separation privilege design principle requires that all resource approved resource access attempts be granted based on more than a single condition. For example a user should be validated for active status and has access to the specific resource. Least Common Mechanism Design PrincipleThe Least Common Mechanism design principle declares that mechanisms used to access resources should not be shared. Psychological Acceptability Design PrincipleThe Psychological Acceptability design principle refers to security mechanisms not make resources more difficult to access than if the security mechanisms were not present Defense in Depth Design PrincipleThe Defense in Depth design principle is a concept of layering resource access authorization verification in a system reduces the chance of a successful attack. This layered approach to resource authorization requires unauthorized users to circumvent each authorization attempt to gain access to a resource. When designing a system that requires meeting a security quality attribute architects need consider the scope of security needs and the minimum required security qualities. Not every system will need to use all of the basic security design principles but will use one or more in combination based on a company’s and architect’s threshold for system security because the existence of security in an application adds an additional layer to the overall system and can affect performance. That is why the definition of minimum security acceptably is need when a system is design because this quality attributes needs to be factored in with the other system quality attributes so that the system in question adheres to all qualities based on the priorities of the qualities. Resources: Barnum, Sean. Gegick, Michael. (2005). Least Privilege. Retrieved on August 28, 2011 from https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/351-BSI.html Saltzer, Jerry. (2011). BASIC PRINCIPLES OF INFORMATION PROTECTION. Retrieved on August 28, 2011 from  http://web.mit.edu/Saltzer/www/publications/protection/Basic.html Barnum, Sean. Gegick, Michael. (2005). Defense in Depth. Retrieved on August 28, 2011 from  https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/347-BSI.html Bertino, Elisa. (2005). Design Principles for Security. Retrieved on August 28, 2011 from  http://homes.cerias.purdue.edu/~bhargav/cs526/security-9.pdf

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• Scheduling thread tiles with C++ AMP

  - by Daniel Moth

  This post assumes you are totally comfortable with, what some of us call, the simple model of C++ AMP, i.e. you could write your own matrix multiplication. We are now ready to explore the tiled model, which builds on top of the non-tiled one. Tiling the extent We know that when we pass a grid (which is just an extent under the covers) to the parallel_for_each call, it determines the number of threads to schedule and their index values (including dimensionality). For the single-, two-, and three- dimensional cases you can go a step further and subdivide the threads into what we call tiles of threads (others may call them thread groups). So here is a single-dimensional example: extent<1> e(20); // 20 units in a single dimension with indices from 0-19 grid<1> g(e);      // same as extent tiled_grid<4> tg = g.tile<4>(); …on the 3rd line we subdivided the single-dimensional space into 5 single-dimensional tiles each having 4 elements, and we captured that result in a concurrency::tiled_grid (a new class in amp.h). Let's move on swiftly to another example, in pictures, this time 2-dimensional: So we start on the left with a grid of a 2-dimensional extent which has 8*6=48 threads. We then have two different examples of tiling. In the first case, in the middle, we subdivide the 48 threads into tiles where each has 4*3=12 threads, hence we have 2*2=4 tiles. In the second example, on the right, we subdivide the original input into tiles where each has 2*2=4 threads, hence we have 4*3=12 tiles. Notice how you can play with the tile size and achieve different number of tiles. The numbers you pick must be such that the original total number of threads (in our example 48), remains the same, and every tile must have the same size. Of course, you still have no clue why you would do that, but stick with me. First, we should see how we can use this tiled_grid, since the parallel_for_each function that we know expects a grid. Tiled parallel_for_each and tiled_index It turns out that we have additional overloads of parallel_for_each that accept a tiled_grid instead of a grid. However, those overloads, also expect that the lambda you pass in accepts a concurrency::tiled_index (new in amp.h), not an index<N>. So how is a tiled_index different to an index? A tiled_index object, can have only 1 or 2 or 3 dimensions (matching exactly the tiled_grid), and consists of 4 index objects that are accessible via properties: global, local, tile_origin, and tile. The global index is the same as the index we know and love: the global thread ID. The local index is the local thread ID within the tile. The tile_origin index returns the global index of the thread that is at position 0,0 of this tile, and the tile index is the position of the tile in relation to the overall grid. Confused? Here is an example accompanied by a picture that hopefully clarifies things: array_view<int, 2> data(8, 6, p_my_data); parallel_for_each(data.grid.tile<2,2>(), [=] (tiled_index<2,2> t_idx) restrict(direct3d) { /* todo */ }); Given the code above and the picture on the right, what are the values of each of the 4 index objects that the t_idx variables exposes, when the lambda is executed by T (highlighted in the picture on the right)? If you can't work it out yourselves, the solution follows: t_idx.global       = index<2> (6,3) t_idx.local          = index<2> (0,1) t_idx.tile_origin = index<2> (6,2) t_idx.tile             = index<2> (3,1) Don't move on until you are comfortable with this… the picture really helps, so use it. Tiled Matrix Multiplication Example – part 1 Let's paste here the C++ AMP matrix multiplication example, bolding the lines we are going to change (can you guess what the changes will be?) 01: void MatrixMultiplyTiled_Part1(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W) 02: { 03: 04: array_view<const float,2> a(M, W, vA); 05: array_view<const float,2> b(W, N, vB); 06: array_view<writeonly<float>,2> c(M, N, vC); 07: parallel_for_each(c.grid, 08: [=](index<2> idx) restrict(direct3d) { 09: 10: int row = idx[0]; int col = idx[1]; 11: float sum = 0.0f; 12: for(int i = 0; i < W; i++) 13: sum += a(row, i) * b(i, col); 14: c[idx] = sum; 15: }); 16: } To turn this into a tiled example, first we need to decide our tile size. Let's say we want each tile to be 16*16 (which assumes that we'll have at least 256 threads to process, and that c.grid.extent.size() is divisible by 256, and moreover that c.grid.extent[0] and c.grid.extent[1] are divisible by 16). So we insert at line 03 the tile size (which must be a compile time constant). 03: static const int TS = 16; ...then we need to tile the grid to have tiles where each one has 16*16 threads, so we change line 07 to be as follows 07: parallel_for_each(c.grid.tile<TS,TS>(), ...that means that our index now has to be a tiled_index with the same characteristics as the tiled_grid, so we change line 08 08: [=](tiled_index<TS, TS> t_idx) restrict(direct3d) { ...which means, without changing our core algorithm, we need to be using the global index that the tiled_index gives us access to, so we insert line 09 as follows 09: index<2> idx = t_idx.global; ...and now this code just works and it is tiled! Closing thoughts on part 1 The process we followed just shows the mechanical transformation that can take place from the simple model to the tiled model (think of this as step 1). In fact, when we wrote the matrix multiplication example originally, the compiler was doing this mechanical transformation under the covers for us (and it has additional smarts to deal with the cases where the total number of threads scheduled cannot be divisible by the tile size). The point is that the thread scheduling is always tiled, even when you use the non-tiled model. But with this mechanical transformation, we haven't gained anything… Hint: our goal with explicitly using the tiled model is to gain even more performance. In the next post, we'll evolve this further (beyond what the compiler can automatically do for us, in this first release), so you can see the full usage of the tiled model and its benefits… Comments about this post by Daniel Moth welcome at the original blog.

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• Master-slave vs. peer-to-peer archictecture: benefits and problems

  - by Ashok_Ora

  Normal 0 false false false EN-US X-NONE X-NONE Almost two decades ago, I was a member of a database development team that introduced adaptive locking. Locking, the most popular concurrency control technique in database systems, is pessimistic. Locking ensures that two or more conflicting operations on the same data item don’t “trample” on each other’s toes, resulting in data corruption. In a nutshell, here’s the issue we were trying to address. In everyday life, traffic lights serve the same purpose. They ensure that traffic flows smoothly and when everyone follows the rules, there are no accidents at intersections. As I mentioned earlier, the problem with typical locking protocols is that they are pessimistic. Regardless of whether there is another conflicting operation in the system or not, you have to hold a lock! Acquiring and releasing locks can be quite expensive, depending on how many objects the transaction touches. Every transaction has to pay this penalty. To use the earlier traffic light analogy, if you have ever waited at a red light in the middle of nowhere with no one on the road, wondering why you need to wait when there’s clearly no danger of a collision, you know what I mean. The adaptive locking scheme that we invented was able to minimize the number of locks that a transaction held, by detecting whether there were one or more transactions that needed conflicting eyou could get by without holding any lock at all. In many “well-behaved” workloads, there are few conflicts, so this optimization is a huge win. If, on the other hand, there are many concurrent, conflicting requests, the algorithm gracefully degrades to the “normal” behavior with minimal cost. We were able to reduce the number of lock requests per TPC-B transaction from 178 requests down to 2! Wow! This is a dramatic improvement in concurrency as well as transaction latency. The lesson from this exercise was that if you can identify the common scenario and optimize for that case so that only the uncommon scenarios are more expensive, you can make dramatic improvements in performance without sacrificing correctness. So how does this relate to the architecture and design of some of the modern NoSQL systems? NoSQL systems can be broadly classified as master-slave sharded, or peer-to-peer sharded systems. NoSQL systems with a peer-to-peer architecture have an interesting way of handling changes. Whenever an item is changed, the client (or an intermediary) propagates the changes synchronously or asynchronously to multiple copies (for availability) of the data. Since the change can be propagated asynchronously, during some interval in time, it will be the case that some copies have received the update, and others haven’t. What happens if someone tries to read the item during this interval? The client in a peer-to-peer system will fetch the same item from multiple copies and compare them to each other. If they’re all the same, then every copy that was queried has the same (and up-to-date) value of the data item, so all’s good. If not, then the system provides a mechanism to reconcile the discrepancy and to update stale copies. So what’s the problem with this? There are two major issues: First, IT’S HORRIBLY PESSIMISTIC because, in the common case, it is unlikely that the same data item will be updated and read from different locations at around the same time! For every read operation, you have to read from multiple copies. That’s a pretty expensive, especially if the data are stored in multiple geographically separate locations and network latencies are high. Second, if the copies are not all the same, the application has to reconcile the differences and propagate the correct value to the out-dated copies. This means that the application program has to handle discrepancies in the different versions of the data item and resolve the issue (which can further add to cost and operation latency). Resolving discrepancies is only one part of the problem. What if the same data item was updated independently on two different nodes (copies)? In that case, due to the asynchronous nature of change propagation, you might land up with different versions of the data item in different copies. In this case, the application program also has to resolve conflicts and then propagate the correct value to the copies that are out-dated or have incorrect versions. This can get really complicated. My hunch is that there are many peer-to-peer-based applications that don’t handle this correctly, and worse, don’t even know it. Imagine have 100s of millions of records in your database – how can you tell whether a particular data item is incorrect or out of date? And what price are you willing to pay for ensuring that the data can be trusted? Multiple network messages per read request? Discrepancy and conflict resolution logic in the application, and potentially, additional messages? All this overhead, when all you were trying to do was to read a data item. Wouldn’t it be simpler to avoid this problem in the first place? Master-slave architectures like the Oracle NoSQL Database handles this very elegantly. A change to a data item is always sent to the master copy. Consequently, the master copy always has the most current and authoritative version of the data item. The master is also responsible for propagating the change to the other copies (for availability and read scalability). Client drivers are aware of master copies and replicas, and client drivers are also aware of the “currency” of a replica. In other words, each NoSQL Database client knows how stale a replica is. This vastly simplifies the job of the application developer. If the application needs the most current version of the data item, the client driver will automatically route the request to the master copy. If the application is willing to tolerate some staleness of data (e.g. a version that is no more than 1 second out of date), the client can easily determine which replica (or set of replicas) can satisfy the request, and route the request to the most efficient copy. This results in a dramatic simplification in application logic and also minimizes network requests (the driver will only send the request to exactl the right replica, not many). So, back to my original point. A well designed and well architected system minimizes or eliminates unnecessary overhead and avoids pessimistic algorithms wherever possible in order to deliver a highly efficient and high performance system. If you’ve every programmed an Oracle NoSQL Database application, you’ll know the difference! /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

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• SQL Navigator startup error: Unhandled Exception at startup - Cannot find OCI DLL: oci.dll

  - by Imageree

  I am using 64 bits Windows 7. Oracle Development Tool: SQL Navigator 5.5 was installed on my computer. When I try to start the program I get this error: "Unhandled Exception at startup - Cannot find OCI DLL: oci.dll" Then I get this error: "Access violation at address 0101916B in module 'SQLNav5.exe'. Read of address 00000000" and then the program is terminatied. Any ideas what is the problem? Update: I am trying to install Oracle client - sql navigator - not sure if the server is 64 bits or not.

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• SQL Navigator startup error: Unhandled Exception at startup - Cannot find OCI DLL: oci.dll

  - by Imageree

  I am using 64 bits Windows 7. Oracle Development Tool: SQL Navigator 5.5 was installed on my computer. When I try to start the program I get this error: "Unhandled Exception at startup - Cannot find OCI DLL: oci.dll" Then I get this error: "Access violation at address 0101916B in module 'SQLNav5.exe'. Read of address 00000000" and then the program is terminatied. Any ideas what is the problem? Update: I am trying to install Oracle client - sql navigator - not sure if the server is 64 bits or not.

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• CodePlex Daily Summary for Friday, May 14, 2010

  CodePlex Daily Summary for Friday, May 14, 2010New ProjectsCampfire#: Campfire# is a campfire client written in .NET 4.0 using WPF, which uses the Campfire API.CHESS: Systematic Concurrency Testing: CHESS is a tool for systematic and disciplined concurrency testing. Given a concurrent test, CHESS systematically enumerates the possible thread sc...cmpp: cmppcycloid: Arcanoid gameDotNetNuke® C#: The DotNetNuke® project is developed and maintained on a Visual Basic codebase, however a C# version has always been a popular request. This is a ...EasyBuildingCMS.NET: EasyBuildingCMS is an easy use content management system.fluidCMS: Provide for flexible management of web content that is not tightly integrated with the layout and rendering of sites that consume the content.Golem: An automation tool oriented to localization engineering environmentHB Batch Encoder Mk 2: HandBrake Batch Encoder Mk II This Program was adapted from an original project downloaded from codeplex by the name of "Handbrake Batch Encoder"...Integrating Social Media Networks: This is part of my pos graduation project.Ketonic: The Ketonic project aims to improve development of websites based on the Kentico CMS. LinkSharp: LinkSharp is a short-URL provider that can be used to generate short static non changing URL's. The web interface allows you to easily add / edit /...PUC NET (C++ Network Library - PUC Minas): This is an Academic Library for an Easy Development of Applications and Games based on Network Communication.Regular Expression Tester: Small utility for testing regular expressionsSharePoint User Management WebPart: SharePoint User Management WebPartSharpBox: SharpBox makes it easier for .NET developers to interact with existing cloud storage service, e.g. DropBox or Amazon S3Snipivit: Snipivit is a snippet manager service and VS2010 plugin that allows small development teams to store all their code snippets on a central database,...Software Factories Applied: Software Factories Applied is a project collecting the companion bits for the eponymous book to be published by Wiley & Sons in 2011. The authors ...The Ping Master: A service that periodically pings network addresses and allows the running of command line type utilities in response to success or failure.Title Safe Region Checker: A simple utility for XNA developers to check screenshots from games intended for release on the LIVE Marketplace for "title safe" region compliance...Trial project: sky is blueUyghur Named Date: Generate Uyghur named date string. ئۇيغۇرچە ئاي ناملىق چىسلا ھاسىل قىلىشWildcard Search Web Part for SharePoint 2010: The Wildcard Search web part for MOSS 2007 was wildly successful. Although, SharePoint 2010 has built-in wildcard searching functionality, the out...在线Office控件 Online Offical Control: 在线Office控件软件作品发布平台: SoftwarePublishPlatform 软件作品发布平台New ReleasesDemina: Demina Binaries version 0.1: Demina binaries are now available. This release (version 0.1) is an alpha version. Please report any bugs for extermination.EasyTFS: EasyTfs 1.0 Beta 2: Added cache refreshing when contents are updated rather than just every 10 minutes. Added window title based on currently-open case. Added attachme...Extending C# editor - Outlining, classification: Initial release: Initial releaseHB Batch Encoder Mk 2: HB Batch Encoder Mk2 v1.01: Binary release files.HB Batch Encoder Mk 2: Source Code: Source CodeHobbyBrew Mobile: Beta 2: Corretti numerosi bug, data un implementazione "approssimativa" del riscaldamento per Infusione. Aggiornamento consigliato!HouseFly controls: HouseFly controls beta 1.0.2.0: HouseFly controls relase 1.0.2.0 betaHtml Reader: Beta 2: I fixed a bug in HtmlElementCollection, Which exposed an integer enumerator, instead of enumerating through HtmlElements. I added a WPF Window tha...Html to OpenXml: HtmlToOpenXml 1.2: Fix some reported bug. See change set for description. The dll library to include in your project. The dll is signed for GAC support. Compiled wi...Infection Protection: Infection Protection 0.1: This is the final version of Infection Protection that was entered into the 2010 OGPC game competition.Jobping Url Shortener: Deploy Code 0.5.1: Deployment code for Version 0.5 This version includes our Jobping style.Jobping Url Shortener: Source Code 0.5.1: Source code for the 0.5 release. This release includes our Jobping style skin.Kooboo HTML form: Kooboo HTML form module 2.1.0.1: HTML form module contributed by member aledelgo. Add SMTP user and password authentication.KooBoo Image Galery: Beta 2: This new version corrects some issues pointed by Guoqi Zheng Some schema and folders were renamed, so it's better to uninstall the module and remo...MFCMAPI: May 2010 Release: If you just want to run the tool, get the executable. If you want to debug it, get the symbol file and the source. Build: 6.0.0.1020 The 64 bit bu...MVC Turbine: Release 2.1 for MVC2: This RTM contains the same features as v2.0 RTM plus these features: Instance Registration to IServiceLocator You can now add an instance of a typ...NazTek.Extension.Clr4: NazTek.Extension.Clr4 Binary: Binary releaseNazTek.Extension.Clr4: NazTek.Extension.Clr4 Source: Cab with source codeNSIS Autorun: NSIS Autorun 0.1.8: This release includes source code, executable binaries and example materials.Ottawa IT Day: 2010 Source Code and Presentations: During the Ottawa IT Day 2010, some of the presenters shared their code (and some presentations). This release is the culmination of all those effo...PHPWord: PHPWord 0.6.1 Beta: Changelog: Fixed Error when adding a JPEG image and opening in office 2007 Issue #1 Fixed Already defined constant PHPWORD_BASE_PATH Issue #2 F...Rapid Dictionary: Rapid Dictionary Alpha 2.0: Release Notes * Try auto updatable version: http://install.rapiddict.com/index.html Rapid Dictionary Alpha 2.0 includes such functionality: ...Shake - C# Make: Shake v0.1.18: Core changes. Process wrapper class, console logger, etc.SharpBox: SharpBox-Trunk: This is the SharpBox build from the trunk source branch!SharpBox: SharpBox-Trunk-Initial-Source: The initial source code, will be updated from time to timeSpackle.NET: 4.0.0.0 Release: This new drop contains the following A CreateBigInteger() method on SecureRandom to create random BigInteger values. An extension method to prop...StreamInsight example queries, input adapters and output adapters: StreamInsight Examples for V1.0 RTM: Zipped source code.The Ping Master: v0.1.0.0: Early release of The Ping Master for test purposes. Configuration tool is unfinished and does not include an installer.Title Safe Region Checker: Title Safe Region Checker v1.0.0.1: Release 1.0 of Title Safe Region Checker. No known bugs or problems. File is a zipped directory containing the necessary installation files.TortoiseHg: TortoiseHg 1.0.3: This is a bug fix release, we recommend all users upgrade to 1.0.3Usa*Usa Libraly: Smart.Windows.Navigation 0.4: Smart.Windows.Navigation simple navigation library ver 0.4.0. Include Windows Forms & Compact Framework samples. Information - Smart.Windows.Mvc ...VCC: Latest build, v2.1.30513.0: Automatic drop of latest buildWabbitStudio Z80 Software Tools: Wabbitcode: Wabbitcode is an Z80 Assembly IDE for Windows, OS X, and Linux. Built to take full advantage of the features of SPASM and Wabbitemu, Wabbitcode has...white: Release 0.20: Source Code: https://white-project.googlecode.com/svn/tags/0.20 Add few more keyboard keys like windows button and F13-F24. Fixed bugs for keyboar...Wildcard Search Web Part for SharePoint 2010: Version 1.0 Release 1: This is the initial release of the Wildcard Search Web Part for SharePoint 2010. All queries will be issued as wildcards unless disabled with the ...Windows Azure Command-line Tools for PHP Developers: Windows Azure Command-line Tools May 2010 Update: May 2010 Update – May 13, 2010 We are pleased to announced the May 2010 update of Windows Azure Command-Line Tools. In addition to bug fixes and i...WinXmlCook: WinXmlCook 2.1: Version 2.1 released!Xrns2XMod: Xrns2XMod 1.1: some source code optimization在线Office控件 Online Offical Control: SPOffice2.0Release: 该版本在MS Office2003/2007，WPS2009，WPS2010下测试通过Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesPHPExcelASP.NETMost Active Projectspatterns & practices – Enterprise LibraryMirror Testing SystemRawrBlogEngine.NETPHPExcelMicrosoft Biology FoundationwhiteWindows Azure Command-line Tools for PHP DevelopersStyleCopShake - C# Make

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• Is it illegal to rewrite every line of an open source project in a slightly different way, and use it in a closed source project?

  - by Chris Barry

  There is some code which is GPL or LGPL that I am considering using for an iPhone project. If I took that code (JavaScript) and rewrote it in a different language for use on the iPhone would that be a legal issue? In theory the process that has happened is that I have gone through each line of the project, learnt what it is doing, and then reimplemented the ideas in a new language. To me it seems this is like learning how to implement something, but then reimplementing it separately from the original licence. Therefore you have only copied the algorithm, which arguably you could have learnt from somewhere else other than the original project. Does the licence cover the specific implementation or the algorithm as well? EDIT------ Really glad to see this topic create a good conversation. To give a bit more backing to the project, the code involved does some kind of audio analysis. I believe it is non-trivial to learn or implement, although I was prepared to embark on this task (I'm at the level where I can implement an FFT algorithm, and this was going to go beyond that.) It is a fairly low LOC script, so I didn't think it would be too hard to do a straight port. I really like the idea of rereleasing my port as well as using it in the application. I don't see any problem with that, and it would be a great way to give something back to the community. I was going to add a line about not wanting to discuss the moral issues, but I'm quite glad I didn't as it seems to have fired the debate a bit. I still feel a bit odd about using open source code to learn from. Does this mean that anything one learns from an open source project is not allowed to be used in a closed source project? And how long after or different does an implementation have to be to not be considered violation of the licence? Murky! EDIT 2 -------- Follow up question

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• SQL Server crashes when remote query fails

  - by Hemanshu Bhojak

  Setup: I have a linked server setup on SQL Server 2005 which is pointing to an Oracle DB. The linked server has RPC enabled. Problem: When a query throws an exception on the remote server (Oracle DB) the SQL Server instance crashes. The logs say that the crash was due to some problem with the RPC call. Is there a way in which I can prevent the entire server to collapse but also use RPC over my linked server. EDIT: Event Log SQL Server is terminating because of fatal exception c0000005. This error may be caused by an unhandled Win32 or C++ exception, or by an access violation encountered during exception handling. Check the SQL error log for any related stack dumps or messages. This exception forces SQL Server to shutdown. To recover from this error, restart the server (unless SQLAgent is configured to auto restart). For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

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• SQL Server crashes when remote query fails

  - by Hemanshu Bhojak

  Setup: I have a linked server setup on SQL Server 2005 which is pointing to an Oracle DB. The linked server has RPC enabled. Problem: When a query throws an exception on the remote server (Oracle DB) the SQL Server instance crashes. The logs say that the crash was due to some problem with the RPC call. Is there a way in which I can prevent the entire server to collapse but also use RPC over my linked server. EDIT: Event Log SQL Server is terminating because of fatal exception c0000005. This error may be caused by an unhandled Win32 or C++ exception, or by an access violation encountered during exception handling. Check the SQL error log for any related stack dumps or messages. This exception forces SQL Server to shutdown. To recover from this error, restart the server (unless SQLAgent is configured to auto restart). For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

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• SRs @ Oracle: How do I License Thee?

  - by [email protected]

  With the release of the new Sun Ray product last week comes the advent of a different software licensing model. Where Sun had initially taken the approach of '1 desktop device = one license', we later changed things to be '1 concurrent connection to the server software = one license', and while there were ways to tell how many connections there were at a time, it wasn't the easiest thing to do.  And, when should you measure concurrency?  At your busiest time, of course... but when might that be?  9:00 Monday morning this week might yield a different result than 9:00 Monday morning last week.In the acquisition of this desktop virtualization product suite Oracle has changed things to be, in typical Oracle fashion, simpler.  There are now two choices for customers around licensing: Named User licenses and Per Device licenses.Here's how they work, and some examples:The Rules1) A Sun Ray device, and PC running the Desktop Access Client (DAC), are both considered unique devices.OR, 2) Any user running a session on either a Sun Ray or an DAC is still just one user.So, you have a choice of path to go down.Some Examples:Here are 6 use cases I can think of right now that will help you choose the Oracle server software licensing model that is right for your business:Case 1If I have 100 Sun Rays for 100 users, and 20 of them use DAC at home that is 100 user licenses.If I have 100 Sun Rays for 100 users, and 20 of them use DAC at home that is 120 device licenses.Two cases using the same metrics - different licensing models and therefore different results.Case 2If I have 100 Sun Rays for 200 users, and 20 of them use DAC at home that is 200 user licenses.If I have 100 Sun Rays for 200 users, and 20 of them use DAC at home that is 120 device licenses.Same metrics - very different results.Case 3If I have 100 Sun Rays for 50 users, and 20 of them use DAC at home that is 50 user licenses.If I have 100 Sun Rays for 50 users, and 20 of them use DAC at home that is 120 device licenses.Same metrics - but again - very different results.Based on the way your business operates you should be able to see which of the two licensing models is most advantageous to you.Got questions?  I'll try to help.(Thanks to Brad Lackey for the clarifications!)

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• Godaddy cname "@" not working (instructions from Heroku).

  - by btelles

  Hi there, I created a little app on Heroku, and am trying to follow their directions for setting up a custom domain on Godaddy. I've created a CNAME for www, but I can't create one for @ (or mydomain.com. per their instructions. I keep getting the error: ERROR - DNS Rules Violation, A record of a different type exists for this hostname, CNAME cannot be created for @ No matter which combination of dots and @'s I use. Anyone know how to add that cname with just the root domain and not the www?

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• Problem with IIS 6.0 in WOW WCF 4 (.net 4.0)

  - by Kevin

  We just upgraded to WCF 4 on IIS 6 (running in WoW 32 bit mode), and all of a sudden the services started running into what appears to be concurrency problems. Upon finding out we had a problem, we changed the Behavior Configuration Changes on the WCF server to the follow: <serviceThrottling maxConcurrentCalls="1000" maxConcurrentInstances="1000" maxConcurrentSessions="1000" /> We also changed the number of worker processes from 1 to 5. Doing all of this seemed to have no effect. The service seemed to be running, but throttled by something. Is there anything else that might need to be changed to remove the "artificial" throttling? Were using the default configuration WCF which should be Per-Call (not singleton).

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• Reminder: True WCF Asynchronous Operation

  - by Sean Feldman

  A true asynchronous service operation is not the one that returns void, but the one that is marked as IsOneWay=true using BeginX/EndX asynchronous operations (thanks Krzysztof). To support this sort of fire-and-forget invocation, Windows Communication Foundation offers one-way operations. After the client issues the call, Windows Communication Foundation generates a request message, but no correlated reply message will ever return to the client. As a result, one-way operations can't return values, and any exception thrown on the service side will not make its way to the client. One-way calls do not equate to asynchronous calls. When one-way calls reach the service, they may not be dispatched all at once and may be queued up on the service side to be dispatched one at a time, all according to the service configured concurrency mode behavior and session mode. How many messages (whether one-way or request-reply) the service is willing to queue up is a product of the configured channel and the reliability mode. If the number of queued messages has exceeded the queue's capacity, then the client will block, even when issuing a one-way call. However, once the call is queued, the client is unblocked and can continue executing while the service processes the operation in the background. This usually gives the appearance of asynchronous calls.

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• PASS 13 Dispatches: Memory Optimized = On

  - by Tony Davis

  I'm at the PASS Summit in Charlotte for the Day 1 keynote by Quentin Clarke, Corporate VP of the data platform group at Microsoft. He's talking about how SQL Server 2014 is “pushing boundaries” and first up is SQL Server 2014's In-Memory OLTP technology (former codename “hekaton”) It is a feature that provokes a lot of interest and for good reason as, without any need for application rewrites or hardware updates, it can enable us to ensure that an application can find in memory most or all of the data it needs, and can lead to huge improvements in processing times. A good recent hekaton use cases article talks about applications that need a “Shock Absorber” when either spikes or just a high rate of incoming workload (including data in ETL scenarios) become a primary bottleneck. To get a really deep look at this technology, I would check out David DeWitt's summit keynote tomorrow (it will be live streamed). Other than that, to get started I'd recommend Kalen Delaney's whitepaper. She offers a lot of insight into how it works and how to start to define memory-optimized tables, and natively compiled stored procedures. These memory-optimized tables uses completely optimistic multi-version concurrency control – no waiting on locks! After that, Tom LaRock has compiled a useful set of links to drill deeper, and includes one to Microsoft's AMR tool to help you gauge the tables that might benefit most. Tony.

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• VS 2010 IDE Features in a nutshell

  - by Rajesh Pillai

  Going through a VS 2010 IDE Features.  We will explore each feature in subsequent posts.  The post are documented as being reviewed by me.   Breakpoint Labeling Breakpoint Searching Breakpoint Import/Export Dynamic Data Tooling WPF Tree Visualizer Call Hierarchy Improved WPF Tooling Historical Debugging Mini-Dump Debugging Quick Search Better Multi-Monitor Support Highlight References Parallel Stacks Window Parallel Tasks Window Document Map Margin Generate from Usage Concurrency Profiler Inline Call Tree Extensible Test Runner MVC Tooling Web Deploy JQuery IntelliSense SharePoint Tooling HTML Snippets Web.config Transformation ClickOnce Enhancements for MS Office     VS is an editor as well as a platform for development and this is only more true with VS 2010.  As an editor there is improved forcus on writing code, understanding code, navigating and publishing code.   VS Shell has been completely rewritten using WPF extending huge benefits.  The start page has been rewritten using XAML, so it is easy to customize.   Support new support for Silverlight, MFC, F# , Azure and extended support for Office 2010, Sharepoint.   Has a good Extension Manager as well.   Enjoy Coding !!!

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• Python HTTPS requests (urllib2) fails on Ubuntu 12.04 without proxy

  - by Pablo

  I have an little app I wrote in Python and it used to work... until yesterday, when it suddenly started giving me an error in a HTTPS connection. I don't remember if there was an update, but both Python 2.7.3rc2 and Python 3.2 are failing just the same. I googled it and found out that this happens when people are behind a proxy, but I'm not (and nothing have changed in my network since the last time it worked). My syster's computer running windows and Python 2.7.2 has no problems (in the same network). response = urllib2.urlopen(url).read() File "/usr/lib/python2.7/urllib2.py", line 126, in urlopen return _opener.open(url, data, timeout) File "/usr/lib/python2.7/urllib2.py", line 400, in open response = self._open(req, data) File "/usr/lib/python2.7/urllib2.py", line 418, in _open '_open', req) File "/usr/lib/python2.7/urllib2.py", line 378, in _call_chain result = func(*args) File "/usr/lib/python2.7/urllib2.py", line 1215, in https_open return self.do_open(httplib.HTTPSConnection, req) File "/usr/lib/python2.7/urllib2.py", line 1177, in do_open raise URLError(err) urllib2.URLError: <urlopen error [Errno 8] _ssl.c:504: EOF occurred in violation of protocol> What's wrong? Any help is appreciated. PS.: Older python versions don't work either, not in my system and not in a live session from USB, but DO work in a Ubuntu 11.10 live session.

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• C# via Java: Introduction

  - by simonc

  Originally posted on: http://geekswithblogs.net/simonc/archive/2013/11/08/c-via-java-introduction.aspxSo, I've recently changed jobs. Rather than working in .NET land, I've migrated over to Java land. But never fear! I'll continue to peer under the covers of .NET, but my next series will use my new experience in Java to explore the design decisions made in the development of the C# programming language. After all, the design of C# was based on Java 1.2, and both languages have continued to evolve since then, incorporating modern software engineering concepts and requirements. Exploring the differences and similarities between the two will (hopefully) give us a deeper understanding into why .NET is implemented the way it is, the trade-offs involved, and what choices were made when new features were designed and added to the language and framework. Among others, I'll be looking at differences in: Primitives Operators Generics Exceptions Accessibility Collections Delegates and inner classes Concurrency In my next post, I'll start off by looking at the type primitives available in each language, and how Java and C# actually incorporate two different concepts of primitive types in their fundamental language design and use. I'm also thinking of looking at the inner details of Java and the JVM in my blogs, as well as C# and the CLR. If you've got any comments or thoughts on this, please let me know.

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• C# via Java: Introduction

  - by Simon Cooper

  So, I’ve recently changed jobs. Rather than working in .NET land, I’ve migrated over to Java land. But never fear! I’ll continue to peer under the covers of .NET, but my next series will use my new experience in Java to explore the design decisions made in the development of the C# programming language. After all, the design of C# was based on Java 1.2, and both languages have continued to evolve since then, incorporating modern software engineering concepts and requirements. Exploring the differences and similarities between the two will (hopefully) give us a deeper understanding into why .NET is implemented the way it is, the trade-offs involved, and what choices were made when new features were designed and added to the language and framework. Among others, I’ll be looking at differences in: Primitives Operators Generics Exceptions Accessibility Collections Delegates and inner classes Concurrency In my next post, I’ll start off by looking at the type primitives available in each language, and how Java and C# actually incorporate two different concepts of primitive types in their fundamental language design and use. I’m also thinking of looking at the inner details of Java and the JVM in my blogs, as well as C# and the CLR. If you’ve got any comments or thoughts on this, please let me know.

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• Configuring jdbc-pool (tomcat 7)

  - by john

  i'm having some problems with tomcat 7 for configuring jdbc-pool : i`ve tried to follow this example: http://www.tomcatexpert.com/blog/2010/04/01/configuring-jdbc-pool-high-concurrency so i have: conf/server.xml <GlobalNamingResources> <Resource type="javax.sql.DataSource" name="jdbc/DB" factory="org.apache.tomcat.jdbc.pool.DataSourceFactory" driverClassName="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/mydb" username="user" password="password" /> </GlobalNamingResources> conf/context.xml <Context> <ResourceLink type="javax.sql.DataSource" name="jdbc/LocalDB" global="jdbc/DB" /> <Context> and when i try to do this: Context initContext = new InitialContext(); Context envContext = (Context)initContext.lookup("java:/comp/env"); DataSource datasource = (DataSource)envContext.lookup("jdbc/LocalDB"); Connection con = datasource.getConnection(); i keep getting this error: javax.naming.NameNotFoundException: Name jdbc is not bound in this Context at org.apache.naming.NamingContext.lookup(NamingContext.java:803) at org.apache.naming.NamingContext.lookup(NamingContext.java:159) pls help tnx

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• How to Configure OpenLDAP on Ubuntu 10.04 Server

  - by user3215

  I am following the Ubuntu server guide to configure OpenLDAP on an Ubuntu 10.04 server, but can not get it to work. When I try to use sudo ldapadd -x -D cn=admin,dc=don,dc=com -W -f frontend.ldif I'm getting the following error: Enter LDAP Password: <entered 'secret' as password> adding new entry "dc=don,dc=com" ldap_add: Naming violation (64) additional info: value of single-valued naming attribute 'dc' conflicts with value present in entry Again when I try to do the same, I'm getting the following error: root@avy-desktop:/home/avy# sudo ldapadd -x -D cn=admin,dc=don,dc=com -W -f frontend.ldif Enter LDAP Password: ldap_bind: Invalid credentials (49) Here is the backend.ldif file: # Load dynamic backend modules dn: cn=module,cn=config objectClass: olcModuleList cn: module olcModulepath: /usr/lib/ldap olcModuleload: back_hdb # Database settings dn: olcDatabase=hdb,cn=config objectClass: olcDatabaseConfig objectClass: olcHdbConfig olcDatabase: {1}hdb olcSuffix: dc=don,dc=com olcDbDirectory: /var/lib/ldap olcRootDN: cn=admin,dc=don,dc=com olcRootPW: secret olcDbConfig: set_cachesize 0 2097152 0 olcDbConfig: set_lk_max_objects 1500 olcDbConfig: set_lk_max_locks 1500 olcDbConfig: set_lk_max_lockers 1500 olcDbIndex: objectClass eq olcLastMod: TRUE olcDbCheckpoint: 512 30 olcAccess: to attrs=userPassword by dn="cn=admin,dc=don,dc=com" write by anonymous auth by self write by * none olcAccess: to attrs=shadowLastChange by self write by * read olcAccess: to dn.base="" by * read olcAccess: to * by dn="cn=admin,dc=don,dc=com" write by * read frontend.ldif file: # Create top-level object in domain dn: dc=don,dc=com objectClass: top objectClass: dcObject objectclass: organization o: Example Organization dc: Example description: LDAP Example # Admin user. dn: cn=admin,dc=don,dc=com objectClass: simpleSecurityObject objectClass: organizationalRole cn: admin description: LDAP administrator userPassword: secret dn: ou=people,dc=don,dc=com objectClass: organizationalUnit ou: people dn: ou=groups,dc=don,dc=com objectClass: organizationalUnit ou: groups dn: uid=john,ou=people,dc=don,dc=com objectClass: inetOrgPerson objectClass: posixAccount objectClass: shadowAccount uid: john sn: Doe givenName: John cn: John Doe displayName: John Doe uidNumber: 1000 gidNumber: 10000 userPassword: password gecos: John Doe loginShell: /bin/bash homeDirectory: /home/john shadowExpire: -1 shadowFlag: 0 shadowWarning: 7 shadowMin: 8 shadowMax: 999999 shadowLastChange: 10877 mail: [email protected] postalCode: 31000 l: Toulouse o: Example mobile: +33 (0)6 xx xx xx xx homePhone: +33 (0)5 xx xx xx xx title: System Administrator postalAddress: initials: JD dn: cn=example,ou=groups,dc=don,dc=com objectClass: posixGroup cn: example gidNumber: 10000 Can anyone help me?

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• "TCP Sweep" - What is it? How am I causing it?

  - by Stephen Melrose

  Hi there, I've just had an email from my hosting company telling me I'm in violation of their Acceptable Use Policy. They forwarded me an email from another company complaining about something to do with a "TCP sweep of port 22". They included a snippet from their logs, 20:29:43 <MY_SERVER_IP> 0.0.0.0 [TCP-SWEEP] (total=325,dp=22,min=212.1.191.0,max=212.1.191.255,Mar21-20:26:34,Mar21-20:26:34) (USI-amsxaid01) Now, my server knowledge is limited at best, and I've absolutely no idea what this is or what could be causing it. Any help would be greatly appreciated! Thank you

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• Announcing Berkeley DB Java Edition Major Release

  - by Eric Jensen

  Berkeley DB Java Edition 5.0 was just released. There are a number of new features, enhancements, and options in there that our users have been asking for. Chief among them is a new class called DiskOrderedCursor, which greatly increases performance of systems using spinning platter magnetic hard drives. A number of users expressed interest in this feature, including Alex Feinberg of LinkedIn. Berkeley DB Java Edition is part of Project Voldemort, a distributed key/value database used by LinkedIn. There have been many other improvements and optimizations. Concurrency is significantly improved, as is the performance of update and delete operations. New and interesting methods include Environment.preload, which allows multiple databases to be preloaded simultaneously. New Cursor methods enable for more effective searching through the database. We continue to enhance Berkeley DB Java Edition’s High Availability as well. One new feature is the ability to open a replicated node read-only when the master is unavailable. This can allow critical systems to continue offering some functionality, even during a network or master node failure. There’s a lot more in release 5.0. I encourage you to take a look at the extensive changelog yourself. As always, you can download the new release and try it out here: http://www.oracle.com/technetwork/database/berkeleydb/downloads/index.html

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