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• Refresh bounded taskflows across regions using InputParameters

  - by raghu.yadav

  Usecase1 : Selecting record from table in left region reflects dependent detail form of same table in right region using InputParameters Here is the example given by Andre Example Three important crux to be known from above example. 1) create primary key attribute in pagedef of the table in region1 2) add inputparameter name in taskflow inputparameters of region2 3) bind primary key attribute from page definition to above inputparameters in main page where above 2 regions dropped. UseCase2 : Selecting record from location table in left region reflects corresponding department records from department table in right regions. 1) create bind variable on location id in departmentVO. 2) create inputparameter say LocationParam, with type Number, value as #{pageFlowScope.LocationParam} 3) assign LocationId param from pagedef to LocationParam in taskflow2 4) create ExecuteWithParam action in region2 pagedef and invoke the same on IfRefresh condition. during run time - steps executes in backwards (3,2,1)..i,e as user selects column in location table, it assigns location from pagedef to locationParam and then to PageFlowScope and from there to view criteria.

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• Part 14: Execute a PowerShell script

  In the series the following parts have been published Part 1: Introduction Part 2: Add arguments and variables Part 3: Use more complex arguments Part 4: Create your own activity Part 5: Increase AssemblyVersion Part 6: Use custom type for an argument Part 7: How is the custom assembly found Part 8: Send information to the build log Part 9: Impersonate activities (run under other credentials) Part 10: Include Version Number in the Build Number Part 11: Speed up opening my build process template Part 12: How to debug my custom activities Part 13: Get control over the Build Output Part 14: Execute a PowerShell script Part 15: Fail a build based on the exit code of a console application With PowerShell you can add powerful scripting to your build to for example execute a deployment. If you want more information on PowerShell, please refer to http://technet.microsoft.com/en-us/library/aa973757.aspx For this example we will create a simple PowerShell script that prints “Hello world!”. To create the script, create a new text file and name it “HelloWorld.ps1”. Add to the contents of the script: Write-Host “Hello World!” To test the script do the following: Open the command prompt To run the script you must change the execution policy. To do this execute in the command prompt: powershell set-executionpolicy remotesigned Now go to the directory where you have saved the PowerShell script Execute the following command powershell .\HelloWorld.ps1 In this example I use a relative path, but when the path to the PowerShell script contains spaces, you need to change the syntax to powershell "& '<full path to script>' " for example: powershell "& ‘C:\sources\Build Customization\SolutionToBuild\PowerShell Scripts\HellloWorld.ps1’ " In this blog post, I create a new solution and that solution includes also this PowerShell script. I want to create an argument on the Build Process Template that holds the path to the PowerShell script. In the Build Process Template I will add an InvokeProcess activity to execute the PowerShell command. This InvokeProcess activity needs the location of the script as an argument for the PowerShell command. Since you don’t know the full path at the build server of this script, you can either specify in the argument the relative path of the script, but it is hard to find out what the relative path is. I prefer to specify the location of the script in source control and then convert that server path to a local path. To do this conversion you can use the ConvertWorkspaceItem activity. So to complete the task, open the Build Process Template CustomTemplate.xaml that we created in earlier parts, follow the following steps Add a new argument called “DeploymentScript” and set the appropriate settings in the metadata. See Part 2: Add arguments and variables  for more information. Scroll down beneath the TryCatch activity called “Try Compile, Test, and Associate Changesets and Work Items” Add a new If activity and set the condition to "Not String.IsNullOrEmpty(DeploymentScript)" to ensure it will only run when the argument is passed. Add in the Then branch of the If activity a new Sequence activity and rename it to “Start deployment” Click on the activity and add a new variable called DeploymentScriptFilename (scoped to the “Start deployment” Sequence Add a ConvertWorkspaceItem activity on the “Start deployment” Sequence Add a InvokeProcess activity beneath the ConvertWorkspaceItem activity in the “Start deployment” Sequence Click on the ConvertWorkspaceItem activity and change the properties DisplayName = Convert deployment script filename Input = DeploymentScript Result = DeploymentScriptFilename Workspace = Workspace Click on the InvokeProcess activity and change the properties Arguments = String.Format(" ""& '{0}' "" ", DeploymentScriptFilename) DisplayName = Execute deployment script FileName = "PowerShell" To see results from the powershell command drop a WriteBuildMessage activity on the "Handle Standard Output" and pass the stdOutput variable to the Message property. Do the same for a WriteBuildError activity on the "Handle Error Output" To publish it, check in the Build Process Template This leads to the following result We now go to the build definition that depends on the template and set the path of the deployment script to the server path to the HelloWorld.ps1. (If you want to see the result of the PowerShell script, change the Logging verbosity to Detailed or Diagnostic). Save and run the build. A lot of the deployment scripts you have will have some kind of arguments (like username / password or environment variables) that you want to define in the Build Definition. To make the PowerShell configurable, you can follow the following steps. Create a new script and give it the name "HelloWho.ps1". In the contents of the file add the following lines: param (         $person     ) $message = [System.String]::Format(“Hello {0}!", $person) Write-Host $message When you now run the script on the command prompt, you will see the following So lets change the Build Process Template to accept one parameter for the deployment script. You can of course make it configurable to add a for-loop that reads through a collection of parameters but that is out of scope of this blog post. Add a new Argument called DeploymentScriptParameter In the InvokeProcess activity where the PowerShell command is executed, modify the Arguments property to String.Format(" ""& '{0}' '{1}' "" ", DeploymentScriptFilename, DeploymentScriptParameter) Check in the Build Process Template Now modify the build definition and set the Parameter of the deployment to any value and run the build. You can download the full solution at BuildProcess.zip. It will include the sources of every part and will continue to evolve.

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• Coding error at open URL

  - by Lobo

  Hi, I have the following method to open a URL API String c=""; URL direccionURL; try { direccionURL = new URL("http://api.stackoverflow.com/1.0/users/523725"); BufferedReader in = new BufferedReader(new InputStreamReader( direccionURL.openStream())); String inputLine; while ((inputLine = in.readLine()) != null) c+=inputLine; in.close(); } catch (MalformedURLException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return c; In the end, the "c" variable contains a set of characters that are not the same I get if I open the same URL with a browser. Why?, What am I doing wrong? Thank's for help. Regards!

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• C# ?? null coalescing operator

  - by anirudha

  the null coalescing operator is used for set the value when object is null. if object have some value that nothing change and still have their default value they have.  string str = "i am string";            string message = str ?? "it is null";   the message have same value as str variable because str not null. if str is null that message have value “it is null”; as declared in statement. coalescing operator does not work on nullable operator such as int?

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• Are there real world applications where the use of prefix versus postfix operators matters?

  - by Kenneth

  In college it is taught how you can do math problems which use the ++ or -- operators on some variable referenced in the equation such that the result of the equation would yield different results if you switched the operator from postfix to prefix or vice versa. Are there any real world applications of using postfix or prefix operator where it makes a difference as to which you use? It doesn't seem to me (maybe I just don't have enough experience yet in programming) that there really is much use to having the different operators if it only applies in math equations. EDIT: Suggestions so far include: function calls //f(++x) != f(x++) loop comparison //while (++i < MAX) != while (i++ < MAX)

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• Platform Builder: Building Cloned Code from Multiple OS Versions

  - by Bruce Eitman

  My career goal is to delete more code than I write, and so far I have been fairly successful. But of course once in a while I need to clone code from the public tree which is contrary to my goal. Usually what follows is a new OS release. To help reach my goal, my team uses the same BSP code for multiple versions of the OS. That means that we need to handle the cloned code so that the correct code builds for the OS version that we are working on. To handle this we could use SKIPBUILD in the sources file, but that gets messy if the cloned code contains multiple folders. The solution that we use is to have a parent folder with subfolders that contain the OS version number. Example: PM |-PM500 |-PM600 |-PM700 The version number corresponds to the environment variable _WINCEOSVER. Then we have a simple DIRS file in the parent folder: DIRS=PM$( _WINCEOSVER) Which automatically selects the folder that goes with the OS version that we are building.   Copyright © 2010 – Bruce Eitman All Rights Reserved

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• Decompilers - Myth or Fact ?

  - by Simon

  Lately I have been thinking of application security and binaries and decompilers. (FYI- Decompilers is just an anti-complier, the purpose is to get the source back from the binary) Is there such thing as "Perfect Decompiler"? or are binaries safe from reverse engineering? (For clarity sake, by "Perfect" I mean the original source files with all the variable names/macros/functions/classes/if possible comments in the respective headers and source files used to get the binary) What are some of the best practices used to prevent reverse engineering of software? Is it a major concern? Also is obfuscation/file permissions the only way to prevent unauthorized hacks on scripts? (call me a script-junky if you should)

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• NullReferenceException when accessing variables in a 2D array in Unity

  - by Syed

  I have made a class including variables in Monodevelop which is: public class GridInfo : MonoBehaviour { public float initPosX; public float initPosY; public bool inUse; public int f; public int g; public int h; public GridInfo parent; public int y,x; } Now I am using its class variable in another class, Map.cs which is: public class Map : MonoBehaviour { public static GridInfo[,] Tile = new GridInfo[17, 23]; void Start() { Tile[0,0].initPosX = initPosX; //Line 49 } } I am not getting any error on runtime, but when I play in unity it is giving me error NullReferenceException: Object reference not set to an instance of an object Map.Start () (at Assets/Scripts/Map.cs:49) I am not inserting this script in any gameobject, as Map.cs will make a GridInfo type array, I have also tried using variables using GetComponent, where is the problem ?

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• SQL SERVER – Install Samples Database Adventure Works for SQL Server 2012

  - by pinaldave

  AdventureWorks is a Sample Database shipped with SQL Server and it can be downloaded from CodePlex site. AdventureWorks has replaced Northwind and Pubs from the sample database in SQL Server 2005.The Microsoft team keeps updating the sample database as they release new versions. For SQL Server 2012 RTM Samples AdventureWorks Database is released: AdventureWorks2012 Data File AdventureWorks2012 Case Sensitive Data File You can download either of the datafile and create database using the same. Here is the script which demonstrates how to create sample database in SQL Server 2012. CREATE DATABASE AdventureWorks2012 ON (FILENAME = 'D:\AdventureWorks2012_Data.mdf') FOR ATTACH_REBUILD_LOG ; Please specify your filepath in the filename variable. Here is the link for additional downloads. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Documentation, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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• Referencing environment variables *in* /etc/environment?

  - by Stefan Kendall

  I recently discovered /etc/environment, which seems a more standard way to setup simple environment variables than scripts, but I was wondering if there was a way to back-reference environment variables in the /etc/environment file. That is, I have this: JAVA_HOME="/tools/java" GRAILS_HOME="/tools/grails" GROOVY_HOME="/tools/groovy" GRADLE_HOME="/tools/gradle" PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" If I try to add $JAVA_HOME/bin to the PATH definition, however, I get $JAVA_HOME/bin, and not the interpolated variable. To remedy this, I'm creating environment.sh in profile.d to add the /bin entries to the path, but this seems sloppy and disorganized. Is there a way to backreference the environment variables in /etc/environment?

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• Dynamically creating astar node map by triangular polygonal map

  - by jett

  My game's map format uses a bunch of triangles to make up the platforms and terrain in 2d. Right now I can set up a 2d array of nodes for the astar algorithm that basically is a bunch of rectangles across the maps x and y that can be set to "wall" if the a* algorithm should try to go around it. However I want a function in the map loader to create the node overlay if the nodes are not specified. I was thinking if more than n percent of the a* rectangle overlaid on map was filled by polygons I could mark that entry in the array as "wall". However I'm stuck on how to do this(or even start) where/when the triangles can be overlapping and also of variable size.

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• Taking the training wheels off: Accelerating the Business with Oracle IAM by Brian Mozinski (Accenture)

  - by Greg Jensen

  Today, technical requirements for IAM are evolving rapidly, and the bar is continuously raised for high performance IAM solutions as organizations look to roll out high volume use cases on the back of legacy systems.  Existing solutions were often designed and architected to support offline transactions and manual processes, and the business owners today demand globally scalable infrastructure to support the growth their business cases are expected to deliver. To help IAM practitioners address these challenges and make their organizations and themselves more successful, this series we will outline the: • Taking the training wheels off: Accelerating the Business with Oracle IAM The explosive growth in expectations for IAM infrastructure, and the business cases they support to gain investment in new security programs. • "Necessity is the mother of invention": Technical solutions developed in the field Well proven tricks of the trade, used by IAM guru’s to maximize your solution while addressing the requirements of global organizations. • The Art & Science of Performance Tuning of Oracle IAM 11gR2 Real world examples of performance tuning with Oracle IAM • No Where to go but up: Extending the benefits of accelerated IAM Anything is possible, compelling new solutions organizations are unlocking with accelerated Oracle IAM Let’s get started … by talking about the changing dynamics driving these discussions. Big Companies are getting bigger everyday, and increasingly organizations operate across state lines, multiple times zones, and in many countries or continents at the same time.  No longer is midnight to 6am a safe time to take down the system for upgrades, to run recon’s and import or update user accounts and attributes.  Further IT organizations are operating as shared services with SLA’s similar to telephone carrier levels expected by their “clients”.  Workers are moved in and out of roles on a weekly, daily, or even hourly rate and IAM is expected to support those rapid changes.  End users registering for services during business hours in Singapore are expected their access to be green-lighted in custom apps hosted in Portugal within the hour.  Many of the expectations of asynchronous systems and batched updates are not adequate and the number and types of users is growing. When organizations acted more like independent teams at functional or geographic levels it was manageable to have processes that relied on a handful of people who knew how to make things work …. Knew how to get you access to the key systems to get your job done.  Today everyone is expected to do more with less, the finance administrator previously supporting their local Atlanta sales office might now be asked to help close the books for the Johannesburg team, and access certification process once completed monthly by Joan on the 3rd floor is now done by a shared pool of resources in Sao Paulo.   Fragmented processes that rely on institutional knowledge to get access to systems and get work done quickly break down in these scenarios.  Highly robust processes that have automated workflows for connected or disconnected systems give organizations the dynamic flexibility to share work across these lines and cut costs or increase productivity. As the IT industry computing paradigms continue to change with the passing of time, and as mature or proven approaches become clear, it is normal for organizations to adjust accordingly. Businesses must manage identity in an increasingly hybrid world in which legacy on-premises IAM infrastructures are extended or replaced to support more and more interconnected and interdependent services to a wider range of users. The old legacy IAM implementation models we had relied on to manage identities no longer apply. End users expect to self-request access to services from their tablet, get supervisor approval over mobile devices and email, and launch the application even if is hosted on the cloud, or run by a partner, vendor, or service provider. While user expectations are higher, they are also simpler … logging into custom desktop apps to request approvals, or going through email or paper based processes for certification is unacceptable.  Users expect security to operate within the paradigm of the application … i.e. feel like the application they are using. Citizen and customer facing applications have evolved from every where, with custom applications, 3rd party tools, and merging in from acquired entities or 3rd party OEM’s resold to expand your portfolio of services.  These all have their own user stores, authentication models, user lifecycles, session management, etc.  Often the designers/developers are no longer accessible and the documentation is limited.  Bringing together underlying directories to scale for growth, and improve user experience is critical for revenue … but also for operations. Job functions are more dynamic.... take the Olympics for example.  Endless organizations from corporations broadcasting, endorsing, or marketing through the event … to non-profit athletic foundations and public/government entities for athletes and public safety, all operate simultaneously on the world stage.  Each organization needs to spin up short-term teams, often dealing with proprietary information from hot ads to racing strategies or security plans.  IAM is expected to enable team’s to spin up, enable new applications, protect privacy, and secure critical infrastructure.  Then it needs to be disabled just as quickly as users go back to their previous responsibilities. On a more technical level … Optimized system directory; tuning guidelines and parameters are needed by businesses today. Business’s need to be making the right choices (virtual directories) and considerations via choosing the correct architectural patterns (virtual, direct, replicated, and tuning), challenge is that business need to assess and chose the correct architectural patters (centralized, virtualized, and distributed) Today's Business organizations have very complex heterogeneous enterprises that contain diverse and multifaceted information. With today's ever changing global landscape, the strategic end goal in challenging times for business is business agility. The business of identity management requires enterprise's to be more agile and more responsive than ever before. The continued proliferation of networking devices (PC, tablet, PDA's, notebooks, etc.) has caused the number of devices and users to be granted access to these devices to grow exponentially. Business needs to deploy an IAM system that can account for the demands for authentication and authorizations to these devices. Increased innovation is forcing business and organizations to centralize their identity management services. Access management needs to handle traditional web based access as well as handle new innovations around mobile, as well as address insufficient governance processes which can lead to rouge identity accounts, which can then become a source of vulnerabilities within a business’s identity platform. Risk based decisions are providing challenges to business, for an adaptive risk model to make proper access decisions via standard Web single sign on for internal and external customers,. Organizations have to move beyond simple login and passwords to address trusted relationship questions such as: Is this a trusted customer, client, or citizen? Is this a trusted employee, vendor, or partner? Is this a trusted device? Without a solid technological foundation, organizational performance, collaboration, constituent services, or any other organizational processes will languish. A Single server location presents not only network concerns for distributed user base, but identity challenges. The network risks are centered on latency of the long trip that the traffic has to take. Other risks are a performance around availability and if the single identity server is lost, all access is lost. As you can see, there are many reasons why performance tuning IAM will have a substantial impact on the success of your organization.  In our next installment in the series we roll up our sleeves and get into detailed tuning techniques used everyday by thought leaders in the field implementing Oracle Identity & Access Management Solutions.

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• Tracking pages with variables in GA

  - by Imran

  Recently I have updated my site, it now passes a variable on some links like so... www.mysite.com/1234/?play=true I've noticed in Google Analytics it records www.mysite.com/1234/ and www.mysite.com/1234/?play=true as two different URL's. Is there a way to merge them because they are after all just one page, It makes "Top Content" for example hard to read because of dupilicates. I've read about something called canonical link tag which may help this? My blog has this already inserted into the head but it doesnt make a difference. Any suggestions?

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• Date and Time Support in SQL Server 2008

  - by Aamir Hasan

    Using the New Date and Time Data Types Normal 0 false false false EN-US X-NONE 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-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-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} 1.       The new date and time data types in SQL Server 2008 offer increased range and precision and are ANSI SQL compatible. 2.       Separate date and time data types minimize storage space requirements for applications that need only date or time information. Moreover, the variable precision of the new time data type increases storage savings in exchange for reduced accuracy. 3.       The new data types are mostly compatible with the original date and time data types and use the same Transact-SQL functions. 4.       The datetimeoffset data type allows you to handle date and time information in global applications that use data that originates from different time zones. SELECT c.name, p.* FROM politics pJOIN country cON p.country = c.codeWHERE YEAR(Independence) < 1753ORDER BY IndependenceGO8.    Highlight the SELECT statement and click Execute ( ) to show the use of some of the date functions.T-SQLSELECT c.name AS [Country Name],        CONVERT(VARCHAR(12), p.Independence, 107) AS [Independence Date],       DATEDIFF(YEAR, p.Independence, GETDATE()) AS [Years Independent (appox)],       p.GovernmentFROM politics pJOIN country cON p.country = c.codeWHERE YEAR(Independence) < 1753ORDER BY IndependenceGO10.    Select the SET DATEFORMAT statement and click Execute ( ) to change the DATEFORMAT to day-month-year.T-SQLSET DATEFORMAT dmyGO11.    Select the DECLARE and SELECT statements and click Execute ( ) to show how the datetime and datetime2 data types interpret a date literal.T-SQLSET DATEFORMAT dmyDECLARE @dt datetime = '2008-12-05'DECLARE @dt2 datetime2 = '2008-12-05'SELECT MONTH(@dt) AS [Month-Datetime], DAY(@dt)     AS [Day-Datetime]SELECT MONTH(@dt2) AS [Month-Datetime2], DAY(@dt2)     AS [Day-Datetime2]GO12.    Highlight the DECLARE and SELECT statements and click Execute ( ) to use integer arithmetic on a datetime variable.T-SQLDECLARE @dt datetime = '2008-12-05'SELECT @dt + 1GO13.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how integer arithmetic is not allowed for datetime2 variables.T-SQLDECLARE @dt2 datetime = '2008-12-05'SELECT @dt2 + 1GO14.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how to use DATE functions to do simple arithmetic on datetime2 variables.T-SQLDECLARE @dt2 datetime2(7) = '2008-12-05'SELECT DATEADD(d, 1, @dt2)GO15.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how the GETDATE function can be used with both datetime and datetime2 data types.T-SQLDECLARE @dt datetime = GETDATE();DECLARE @dt2 datetime2(7) = GETDATE();SELECT @dt AS [GetDate-DateTime], @dt2 AS [GetDate-DateTime2]GO16.    Draw attention to the values returned for both columns and how they are equal.17.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how the SYSDATETIME function can be used with both datetime and datetime2 data types.T-SQLDECLARE @dt datetime = SYSDATETIME();DECLARE @dt2 datetime2(7) = SYSDATETIME();SELECT @dt AS [Sysdatetime-DateTime], @dt2     AS [Sysdatetime-DateTime2]GO18.    Draw attention to the values returned for both columns and how they are different.Programming Global Applications with DateTimeOffset 2.    If you have not previously created the SQLTrainingKitDB database while completing another demo in this training kit, highlight the CREATE DATABASE statement and click Execute ( ) to do so now.T-SQLCREATE DATABASE SQLTrainingKitDBGO3.    Select the USE and CREATE TABLE statements and click Execute ( ) to create table datetest in the SQLTrainingKitDB database.T-SQLUSE SQLTrainingKitDBGOCREATE TABLE datetest (  id integer IDENTITY PRIMARY KEY,  datetimecol datetimeoffset,  EnteredTZ varchar(40)); Reference:http://www.microsoft.com/downloads/details.aspx?FamilyID=E9C68E1B-1E0E-4299-B498-6AB3CA72A6D7&displaylang=en   

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• How do I deal with analysis paralysis?

  - by Anne Nonimus

  Very frequently, I am stuck when choosing the best design decision. Even for small details, such as function definitions, control flow, and variable names, I spend unusually long periods perusing the benefits and trade-offs of my choices. I feel like I am losing a lot of efficiency by spending my hours on insignificant details like these. Even though, I know in the back of my mind that I can change these things if my current design doesn't work out, I have trouble deciding firmly on one choice. What should I do to combat this problem?

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• Installing a DHCP Service On Win2k8 ( Windows Server 2008 )

  - by Akshay Deep Lamba

  Introduction Dynamic Host Configuration Protocol (DHCP) is a core infrastructure service on any network that provides IP addressing and DNS server information to PC clients and any other device. DHCP is used so that you do not have to statically assign IP addresses to every device on your network and manage the issues that static IP addressing can create. More and more, DHCP is being expanded to fit into new network services like the Windows Health Service and Network Access Protection (NAP). However, before you can use it for more advanced services, you need to first install it and configure the basics. Let’s learn how to do that. Installing Windows Server 2008 DHCP Server Installing Windows Server 2008 DCHP Server is easy. DHCP Server is now a “role” of Windows Server 2008 – not a windows component as it was in the past. To do this, you will need a Windows Server 2008 system already installed and configured with a static IP address. You will need to know your network’s IP address range, the range of IP addresses you will want to hand out to your PC clients, your DNS server IP addresses, and your default gateway. Additionally, you will want to have a plan for all subnets involved, what scopes you will want to define, and what exclusions you will want to create. To start the DHCP installation process, you can click Add Roles from the Initial Configuration Tasks window or from Server Manager à Roles à Add Roles. Figure 1: Adding a new Role in Windows Server 2008 When the Add Roles Wizard comes up, you can click Next on that screen. Next, select that you want to add the DHCP Server Role, and click Next. Figure 2: Selecting the DHCP Server Role If you do not have a static IP address assigned on your server, you will get a warning that you should not install DHCP with a dynamic IP address. At this point, you will begin being prompted for IP network information, scope information, and DNS information. If you only want to install DHCP server with no configured scopes or settings, you can just click Next through these questions and proceed with the installation. On the other hand, you can optionally configure your DHCP Server during this part of the installation. In my case, I chose to take this opportunity to configure some basic IP settings and configure my first DHCP Scope. I was shown my network connection binding and asked to verify it, like this: Figure 3: Network connection binding What the wizard is asking is, “what interface do you want to provide DHCP services on?” I took the default and clicked Next. Next, I entered my Parent Domain, Primary DNS Server, and Alternate DNS Server (as you see below) and clicked Next. Figure 4: Entering domain and DNS information I opted NOT to use WINS on my network and I clicked Next. Then, I was promoted to configure a DHCP scope for the new DHCP Server. I have opted to configure an IP address range of 192.168.1.50-100 to cover the 25+ PC Clients on my local network. To do this, I clicked Add to add a new scope. As you see below, I named the Scope WBC-Local, configured the starting and ending IP addresses of 192.168.1.50-192.168.1.100, subnet mask of 255.255.255.0, default gateway of 192.168.1.1, type of subnet (wired), and activated the scope. Figure 5: Adding a new DHCP Scope Back in the Add Scope screen, I clicked Next to add the new scope (once the DHCP Server is installed). I chose to Disable DHCPv6 stateless mode for this server and clicked Next. Then, I confirmed my DHCP Installation Selections (on the screen below) and clicked Install. Figure 6: Confirm Installation Selections After only a few seconds, the DHCP Server was installed and I saw the window, below: Figure 7: Windows Server 2008 DHCP Server Installation succeeded I clicked Close to close the installer window, then moved on to how to manage my new DHCP Server. How to Manage your new Windows Server 2008 DHCP Server Like the installation, managing Windows Server 2008 DHCP Server is also easy. Back in my Windows Server 2008 Server Manager, under Roles, I clicked on the new DHCP Server entry. Figure 8: DHCP Server management in Server Manager While I cannot manage the DHCP Server scopes and clients from here, what I can do is to manage what events, services, and resources are related to the DHCP Server installation. Thus, this is a good place to go to check the status of the DHCP Server and what events have happened around it. However, to really configure the DHCP Server and see what clients have obtained IP addresses, I need to go to the DHCP Server MMC. To do this, I went to Start à Administrative Tools à DHCP Server, like this: Figure 9: Starting the DHCP Server MMC When expanded out, the MMC offers a lot of features. Here is what it looks like: Figure 10: The Windows Server 2008 DHCP Server MMC The DHCP Server MMC offers IPv4 & IPv6 DHCP Server info including all scopes, pools, leases, reservations, scope options, and server options. If I go into the address pool and the scope options, I can see that the configuration we made when we installed the DHCP Server did, indeed, work. The scope IP address range is there, and so are the DNS Server & default gateway. Figure 11: DHCP Server Address Pool Figure 12: DHCP Server Scope Options So how do we know that this really works if we do not test it? The answer is that we do not. Now, let’s test to make sure it works. How do we test our Windows Server 2008 DHCP Server? To test this, I have a Windows Vista PC Client on the same network segment as the Windows Server 2008 DHCP server. To be safe, I have no other devices on this network segment. I did an IPCONFIG /RELEASE then an IPCONFIG /RENEW and verified that I received an IP address from the new DHCP server, as you can see below: Figure 13: Vista client received IP address from new DHCP Server Also, I went to my Windows 2008 Server and verified that the new Vista client was listed as a client on the DHCP server. This did indeed check out, as you can see below: Figure 14: Win 2008 DHCP Server has the Vista client listed under Address Leases With that, I knew that I had a working configuration and we are done!

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• F# for the C# Programmer

  - by mbcrump

  Are you a C# Programmer and can’t make it past a day without seeing or hearing someone mention F#?  Today, I’m going to walk you through your first F# application and give you a brief introduction to the language. Sit back this will only take about 20 minutes. Introduction Microsoft's F# programming language is a functional language for the .NET framework that was originally developed at Microsoft Research Cambridge by Don Syme. In October 2007, the senior vice president of the developer division at Microsoft announced that F# was being officially productized to become a fully supported .NET language and professional developers were hired to create a team of around ten people to build the product version. In September 2008, Microsoft released the first Community Technology Preview (CTP), an official beta release, of the F# distribution . In December 2008, Microsoft announced that the success of this CTP had encouraged them to escalate F# and it is now will now be shipped as one of the core languages in Visual Studio 2010 , alongside C++, C# 4.0 and VB. The F# programming language incorporates many state-of-the-art features from programming language research and ossifies them in an industrial strength implementation that promises to revolutionize interactive, parallel and concurrent programming. Advantages of F# F# is the world's first language to combine all of the following features: Type inference: types are inferred by the compiler and generic definitions are created automatically. Algebraic data types: a succinct way to represent trees. Pattern matching: a comprehensible and efficient way to dissect data structures. Active patterns: pattern matching over foreign data structures. Interactive sessions: as easy to use as Python and Mathematica. High performance JIT compilation to native code: as fast as C#. Rich data structures: lists and arrays built into the language with syntactic support. Functional programming: first-class functions and tail calls. Expressive static type system: finds bugs during compilation and provides machine-verified documentation. Sequence expressions: interrogate huge data sets efficiently. Asynchronous workflows: syntactic support for monadic style concurrent programming with cancellations. Industrial-strength IDE support: multithreaded debugging, and graphical throwback of inferred types and documentation. Commerce friendly design and a viable commercial market. Lets try a short program in C# then F# to understand the differences. Using C#: Create a variable and output the value to the console window: Sample Program. using System;   namespace ConsoleApplication9 {     class Program     {         static void Main(string[] args)         {             var a = 2;             Console.WriteLine(a);             Console.ReadLine();         }     } } A breeze right? 14 Lines of code. We could have condensed it a bit by removing the “using” statment and tossing the namespace. But this is the typical C# program. Using F#: Create a variable and output the value to the console window: To start, open Visual Studio 2010 or Visual Studio 2008. Note: If using VS2008, then please download the SDK first before getting started. If you are using VS2010 then you are already setup and ready to go. So, click File-> New Project –> Other Languages –> Visual F# –> Windows –> F# Application. You will get the screen below. Go ahead and enter a name and click OK. Now, you will notice that the Solution Explorer contains the following: Double click the Program.fs and enter the following information. Hit F5 and it should run successfully. Sample Program. open System let a = 2        Console.WriteLine a As Shown below: Hmm, what? F# did the same thing in 3 lines of code. Show me the interactive evaluation that I keep hearing about. The F# development environment for Visual Studio 2010 provides two different modes of execution for F# code: Batch compilation to a .NET executable or DLL. (This was accomplished above). Interactive evaluation. (Demo is below) The interactive session provides a > prompt, requires a double semicolon ;; identifier at the end of a code snippet to force evaluation, and returns the names (if any) and types of resulting definitions and values. To access the F# prompt, in VS2010 Goto View –> Other Window then F# Interactive. Once you have the interactive window type in the following expression: 2+3;; as shown in the screenshot below: I hope this guide helps you get started with the language, please check out the following books for further information. F# Books for further reading   Foundations of F# Author: Robert Pickering An introduction to functional programming with F#. Including many samples, this book walks through the features of the F# language and libraries, and covers many of the .NET Framework features which can be leveraged with F#.       Functional Programming for the Real World: With Examples in F# and C# Authors: Tomas Petricek and Jon Skeet An introduction to functional programming for existing C# developers written by Tomas Petricek and Jon Skeet. This book explains the core principles using both C# and F#, shows how to use functional ideas when designing .NET applications and presents practical examples such as design of domain specific language, development of multi-core applications and programming of reactive applications.

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• Getting ADB to run

  - by gh0st_h4wk

  I've recently installed ubuntu and I need Android SDK (and subsequently, adb) in order to develop my apps to college. The fact is that, no matter what I do, I can't get adb to work. Exporting its place to the PATH didn't worked. I only get "file or directory not found" error while this are the contents of the PATH variable: renan@RocketQueen:~$ echo $PATH /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/home/renan/adt/sdk/tools:/home/renan/adt/sdk/platform-tools I don't want to install android-tools-adb/fastboot because they're outdate when compared to SDK Manager ones. What do I need to do in order for it to work from anywhere when called from terminal?

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• Resetting Your Oracle User Password with SQL Developer

  - by thatjeffsmith

  There’s nothing more annoying than having to email, call, or log a support ticket to have one of your accounts reset. This is no less annoying in the Oracle database. Those pesky security folks have determined that your password should only be valid for X days, and your time is up. Time to reset the password! Except…you can’t log into the database to reset your password. What now? Wait a second, look at this nifty thing I see in SQL Developer: Right click on my connection, reset password not available! Why not? The JDBC Driver Doesn’t Support This Operation We can’t make this call over the Oracle JDBC layer, because it hasn’t been implemented. However our primary interface, OCI, does indeed support this. In order to use the Oracle Call Interface (OCI), you need to have an Oracle Client on your machine. The good news is that this is fairly easy to get going. The Instant Client will do. You have two options, the full or ‘Lite’ Instant Clients. If you want SQL*Plus and the other client tools, go for the full. If you just want the basic drivers, go for the Lite. Either of these is fine, but mind the bit level and version of Oracle! Make sure you get a 32 bit Instant Client if you run 32 bit SQL Developer or 64 bit if you run 64 Here’s the download link What, you didn’t believe me? Mind the version of Oracle too! You want to be at the same level or higher of the database you’re working with. You can use a 11.2.0.3 client with 11.2.0.1 database but not a 10gR2 client with 11gR2 database. Clear as mud? Download and Extract Put it where you want – Program Files is as good as place as any if you have the rights. When you’re done, copy that directory path you extracted the archive to, because we’re going to add it to your Windows PATH environment variable. The easiest way to find this in Windows 7 is to open the Start dialog and type ‘path’. In Windows 8 you’ll cast your spell and wave at your screen until something happens. I recommend you put it up front so we find our DLLs first. Now with that set, let’s start up SQL Developer. Check the Connection Context menu again Bingo! What happened there? SQL Developer looks to see if it can find the OCI resources. Guess where it looks? That’s right, the PATH. If it finds what it’s looking for, and confirms the bit level is right, it will activate the Reset Password option. We have a Preference to ‘force’ an OCI/THICK connection that gives you a few other edge case features, but you do not need to enable this to activate the Reset Password. Not necessary, but won’t hurt anything either. There are a few actual benefits to using OCI powered connections, but that’s beyond the scope of today’s blog post…to be continued. Ok, so we’re ready to go. Now, where was I again? Oh yeah, my password has expired… Right click on your connection and now choose ‘Reset Password’ You’ll need to know your existing password and select a new one that meets your databases’s security standards. I Need Another Option, This Ain’t Working! If you have another account in the database, you can use the DBA Panel to reset a user’s password, or of course you can spark up a SQL*Plus session and issue the ALTER USER JEFF IDENTIFIED BY _________; command – but you knew this already, yes? I need more help ‘installing’ the Instant Client, help! There are lots and lots of resources out there on this subject. But I also know from personal experience that many of you have problems getting this to ‘work.’ The key things to remember is to download the right bit level AND make sure the client install directory is in your path. I know many folks that will just ‘install’ the Instant Client directly to one of their ‘bin’ type directories. You can do that if you want, but I prefer the cleaner method. Of course if you lack admin privs to change the PATH variable, that might be your only option. Or you could do what the original ORA- message indicated and ‘contact your DBA.’

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• what are the benefits of closure, primarily for PHP?

  - by Patrick

  I am beginning the process of moving code over to PHP 5.3 and one of the most highly touted features of PHP 5.3 is the ability to use closures. My understanding of closures is that they allow anonymous functions, can be assigned to variable names, and have interesting scoping abilities. From my point of view the only seeming benefits in real world applications is the reduction of clutter in the namespace because closures are anonymous. Am I wrong in this? Should I be trying to put closures wherever I code? EDIT: I have already read this post on Javascript closures.

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• Adding new events to be handled by script part without recompilation of c++ source code

  - by paul424

  As in title I want to write an Event system with handling methods written in external script language, that is Angelscript. The AS methods would have acess to game's world modifing API ( which has to be regsitered for Angelscript Machine as the game starts) . I have come to this problem : if we use the Angelsript for rapid prototyping of the game's world behavior , we would like to be able to define new Event Types, without recompiling the main binary. Is that ever possible , don't stick to Angelscript, I think about any possible scripting language. The main thought is this : If there's some really new Event possible to be constructed , we must monitor some information coming from the binary, for example some variable value changing and the Events are just triggered on some conditions on those changes , wer might be monitoring the Creatures HP, by having a function call on each change, there we could define new Events such as Creature hurt, creature killed, creature healed , creature killed and tormented to pieces ( like geting HP very much below 0 ) . Are there any other ideas of constructing new Events at the scripting side ?

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• A New Threat To Web Applications: Connection String Parameter Pollution (CSPP)

  - by eric.maurice

  Hi, this is Shaomin Wang. I am a security analyst in Oracle's Security Alerts Group. My primary responsibility is to evaluate the security vulnerabilities reported externally by security researchers on Oracle Fusion Middleware and to ensure timely resolution through the Critical Patch Update. Today, I am going to talk about a serious type of attack: Connection String Parameter Pollution (CSPP). Earlier this year, at the Black Hat DC 2010 Conference, two Spanish security researchers, Jose Palazon and Chema Alonso, unveiled a new class of security vulnerabilities, which target insecure dynamic connections between web applications and databases. The attack called Connection String Parameter Pollution (CSPP) exploits specifically the semicolon delimited database connection strings that are constructed dynamically based on the user inputs from web applications. CSPP, if carried out successfully, can be used to steal user identities and hijack web credentials. CSPP is a high risk attack because of the relative ease with which it can be carried out (low access complexity) and the potential results it can have (high impact). In today's blog, we are going to first look at what connection strings are and then review the different ways connection string injections can be leveraged by malicious hackers. We will then discuss how CSPP differs from traditional connection string injection, and the measures organizations can take to prevent this kind of attacks. In web applications, a connection string is a set of values that specifies information to connect to backend data repositories, in most cases, databases. The connection string is passed to a provider or driver to initiate a connection. Vendors or manufacturers write their own providers for different databases. Since there are many different providers and each provider has multiple ways to make a connection, there are many different ways to write a connection string. Here are some examples of connection strings from Oracle Data Provider for .Net/ODP.Net: Oracle Data Provider for .Net / ODP.Net; Manufacturer: Oracle; Type: .NET Framework Class Library: - Using TNS Data Source = orcl; User ID = myUsername; Password = myPassword; - Using integrated security Data Source = orcl; Integrated Security = SSPI; - Using the Easy Connect Naming Method Data Source = username/password@//myserver:1521/my.server.com - Specifying Pooling parameters Data Source=myOracleDB; User Id=myUsername; Password=myPassword; Min Pool Size=10; Connection Lifetime=120; Connection Timeout=60; Incr Pool Size=5; Decr Pool Size=2; There are many variations of the connection strings, but the majority of connection strings are key value pairs delimited by semicolons. Attacks on connection strings are not new (see for example, this SANS White Paper on Securing SQL Connection String). Connection strings are vulnerable to injection attacks when dynamic string concatenation is used to build connection strings based on user input. When the user input is not validated or filtered, and malicious text or characters are not properly escaped, an attacker can potentially access sensitive data or resources. For a number of years now, vendors, including Oracle, have created connection string builder class tools to help developers generate valid connection strings and potentially prevent this kind of vulnerability. Unfortunately, not all application developers use these utilities because they are not aware of the danger posed by this kind of attacks. So how are Connection String parameter Pollution (CSPP) attacks different from traditional Connection String Injection attacks? First, let's look at what parameter pollution attacks are. Parameter pollution is a technique, which typically involves appending repeating parameters to the request strings to attack the receiving end. Much of the public attention around parameter pollution was initiated as a result of a presentation on HTTP Parameter Pollution attacks by Stefano Di Paola and Luca Carettoni delivered at the 2009 Appsec OWASP Conference in Poland. In HTTP Parameter Pollution attacks, an attacker submits additional parameters in HTTP GET/POST to a web application, and if these parameters have the same name as an existing parameter, the web application may react in different ways depends on how the web application and web server deal with multiple parameters with the same name. When applied to connections strings, the rule for the majority of database providers is the "last one wins" algorithm. If a KEYWORD=VALUE pair occurs more than once in the connection string, the value associated with the LAST occurrence is used. This opens the door to some serious attacks. By way of example, in a web application, a user enters username and password; a subsequent connection string is generated to connect to the back end database. Data Source = myDataSource; Initial Catalog = db; Integrated Security = no; User ID = myUsername; Password = XXX; In the password field, if the attacker enters "xxx; Integrated Security = true", the connection string becomes, Data Source = myDataSource; Initial Catalog = db; Integrated Security = no; User ID = myUsername; Password = XXX; Intergrated Security = true; Under the "last one wins" principle, the web application will then try to connect to the database using the operating system account under which the application is running to bypass normal authentication. CSPP poses serious risks for unprepared organizations. It can be particularly dangerous if an Enterprise Systems Management web front-end is compromised, because attackers can then gain access to control panels to configure databases, systems accounts, etc. Fortunately, organizations can take steps to prevent this kind of attacks. CSPP falls into the Injection category of attacks like Cross Site Scripting or SQL Injection, which are made possible when inputs from users are not properly escaped or sanitized. Escaping is a technique used to ensure that characters (mostly from user inputs) are treated as data, not as characters, that is relevant to the interpreter's parser. Software developers need to become aware of the danger of these attacks and learn about the defenses mechanism they need to introduce in their code. As well, software vendors need to provide templates or classes to facilitate coding and eliminate developers' guesswork for protecting against such vulnerabilities. Oracle has introduced the OracleConnectionStringBuilder class in Oracle Data Provider for .NET. Using this class, developers can employ a configuration file to provide the connection string and/or dynamically set the values through key/value pairs. It makes creating connection strings less error-prone and easier to manager, and ultimately using the OracleConnectionStringBuilder class provides better security against injection into connection strings. For More Information: - The OracleConnectionStringBuilder is located at http://download.oracle.com/docs/cd/B28359_01/win.111/b28375/OracleConnectionStringBuilderClass.htm - Oracle has developed a publicly available course on preventing SQL Injections. The Server Technologies Curriculum course "Defending Against SQL Injection Attacks!" is located at http://st-curriculum.oracle.com/tutorial/SQLInjection/index.htm - The OWASP web site also provides a number of useful resources. It is located at http://www.owasp.org/index.php/Main_Page

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• ifconfig : Command 'ifconfig' is available in '/sbin/ifconfig'

  - by Sahil Grover

  My question is related to another open question. My echo $PATH gives me an output which is like /home/sahil/.rvm/gems/ruby-1.9.3-p125/bin:/home/sahil/.rvm/gems/ruby-1.9.3-p125@global/bin:/home/sahil/.rvm/rubies/ruby-1.9.3-p125/bin:/home/sahil/.rvm/bin:/usr/local/bin:/usr/bin:/bin:/usr/games:/home/sahil/.rvm/bin{}:/home/android-sdks/{}:/home/android-sdks/platform-tools/{}:/home/android-sdks/tools/{}:/home/sahil/android-sdks/tools{}:/home/sahil/android-sdks/tools:/home/sahil/android-sdks/platform-tools/ But running ifconfig gives me an output like Command 'ifconfig' is available in '/sbin/ifconfig' The command could not be located because '/sbin' is not included in the PATH environment variable. This is most likely caused by the lack of administrative privileges associated with your user account. ifconfig: command not found after running command like given in other question export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" it runs ifconfig but blocks other commands of ruby rails or rvm. Seeking help how to resolve this. Also why this happens?

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• Tuning Red Gate: #4 of Some

  - by Grant Fritchey

  First time connecting to these servers directly (keys to the kingdom, bwa-ha-ha-ha. oh, excuse me), so I'm going to take a look at the server properties, just to see if there are any issues there. Max memory is set, cool, first possible silly mistake clear. In fact, these look to be nicely set up. Oh, I'd like to see the ANSI Standards set by default, but it's not a big deal. The default location for database data is the F:\ drive, where I saw all the activity last time. Cool, the people maintaining the servers in our company listen, parallelism threshold is set to 35 and optimize for ad hoc is enabled. No shocks, no surprises. The basic setup is appropriate. On to the problem database. Nothing wrong in the properties. The database is in SIMPLE recovery, but I think it's a reporting system, so no worries there. Again, I'd prefer to see the ANSI settings for connections, but that's the worst thing I can see. Time to look at the queries, tables, indexes and statistics because all the information I've collected over the last several days suggests that we're not looking at a systemic problem (except possibly not enough memory), but at the traditional tuning issues. I just want to note that, I started looking at the system, not the queries. So should you when tuning your environment. I know, from the data collected through SQL Monitor, what my top poor performing queries are, and the most frequently called, etc. I'm starting with the most frequently called. I'm going to get the execution plan for this thing out of the cache (although, with the cache dumping constantly, I might not get it). And it's not there. Called 1.3 million times over the last 3 days, but it's not in cache. Wow. OK. I'll see what's in cache for this database: SELECT  deqs.creation_time,         deqs.execution_count,         deqs.max_logical_reads,         deqs.max_elapsed_time,         deqs.total_logical_reads,         deqs.total_elapsed_time,         deqp.query_plan,         SUBSTRING(dest.text, (deqs.statement_start_offset / 2) + 1,                   (deqs.statement_end_offset - deqs.statement_start_offset) / 2                   + 1) AS QueryStatement FROM    sys.dm_exec_query_stats AS deqs         CROSS APPLY sys.dm_exec_sql_text(deqs.sql_handle) AS dest         CROSS APPLY sys.dm_exec_query_plan(deqs.plan_handle) AS deqp WHERE   dest.dbid = DB_ID('Warehouse') AND deqs.statement_end_offset > 0 AND deqs.statement_start_offset > 0 ORDER BY deqs.max_logical_reads DESC ; And looking at the most expensive operation, we have our first bad boy: Multiple table scans against very large sets of data and a sort operation. a sort operation? It's an insert. Oh, I see, the table is a heap, so it's doing an insert, then sorting the data and then inserting into the primary key. First question, why isn't this a clustered index? Let's look at some more of the queries. The next one is deceiving. Here's the query plan: You're thinking to yourself, what's the big deal? Well, what if I told you that this thing had 8036318 reads? I know, you're looking at skinny little pipes. Know why? Table variable. Estimated number of rows = 1. Actual number of rows. well, I'm betting several more than one considering it's read 8 MILLION pages off the disk in a single execution. We have a serious and real tuning candidate. Oh, and I missed this, it's loading the table variable from a user defined function. Let me check, let me check. YES! A multi-statement table valued user defined function. And another tuning opportunity. This one's a beauty, seriously. Did I also mention that they're doing a hash against all the columns in the physical table. I'm sure that won't lead to scans of a 500,000 row table, no, not at all. OK. I lied. Of course it is. At least it's on the top part of the Loop which means the scan is only executed once. I just did a cursory check on the next several poor performers. all calling the UDF. I think I found a big tuning opportunity. At this point, I'm typing up internal emails for the company. Someone just had their baby called ugly. In addition to a series of suggested changes that we need to implement, I'm also apologizing for being such an unkind monster as to question whether that third eye & those flippers belong on such an otherwise lovely child.

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• Nashorn, the rhino in the room

  - by costlow

  Nashorn is a new runtime within JDK 8 that allows developers to run code written in JavaScript and call back and forth with Java. One advantage to the Nashorn scripting engine is that is allows for quick prototyping of functionality or basic shell scripts that use Java libraries. The previous JavaScript runtime, named Rhino, was introduced in JDK 6 (released 2006, end of public updates Feb 2013). Keeping tradition amongst the global developer community, "Nashorn" is the German word for rhino. The Java platform and runtime is an intentional home to many languages beyond the Java language itself. OpenJDK’s Da Vinci Machine helps coordinate work amongst language developers and tool designers and has helped different languages by introducing the Invoke Dynamic instruction in Java 7 (2011), which resulted in two major benefits: speeding up execution of dynamic code, and providing the groundwork for Java 8’s lambda executions. Many of these improvements are discussed at the JVM Language Summit, where language and tool designers get together to discuss experiences and issues related to building these complex components. There are a number of benefits to running JavaScript applications on JDK 8’s Nashorn technology beyond writing scripts quickly: Interoperability with Java and JavaScript libraries. Scripts do not need to be compiled. Fast execution and multi-threading of JavaScript running in Java’s JRE. The ability to remotely debug applications using an IDE like NetBeans, Eclipse, or IntelliJ (instructions on the Nashorn blog). Automatic integration with Java monitoring tools, such as performance, health, and SIEM. In the remainder of this blog post, I will explain how to use Nashorn and the benefit from those features. Nashorn execution environment The Nashorn scripting engine is included in all versions of Java SE 8, both the JDK and the JRE. Unlike Java code, scripts written in nashorn are interpreted and do not need to be compiled before execution. Developers and users can access it in two ways: Users running JavaScript applications can call the binary directly:jre8/bin/jjs This mechanism can also be used in shell scripts by specifying a shebang like #!/usr/bin/jjs Developers can use the API and obtain a ScriptEngine through:ScriptEngine engine = new ScriptEngineManager().getEngineByName("nashorn"); When using a ScriptEngine, please understand that they execute code. Avoid running untrusted scripts or passing in untrusted/unvalidated inputs. During compilation, consider isolating access to the ScriptEngine and using Type Annotations to only allow @Untainted String arguments. One noteworthy difference between JavaScript executed in or outside of a web browser is that certain objects will not be available. For example when run outside a browser, there is no access to a document object or DOM tree. Other than that, all syntax, semantics, and capabilities are present. Examples of Java and JavaScript The Nashorn script engine allows developers of all experience levels the ability to write and run code that takes advantage of both languages. The specific dialect is ECMAScript 5.1 as identified by the User Guide and its standards definition through ECMA international. In addition to the example below, Benjamin Winterberg has a very well written Java 8 Nashorn Tutorial that provides a large number of code samples in both languages. Basic Operations A basic Hello World application written to run on Nashorn would look like this: #!/usr/bin/jjs print("Hello World"); The first line is a standard script indication, so that Linux or Unix systems can run the script through Nashorn. On Windows where scripts are not as common, you would run the script like: jjs helloWorld.js. Receiving Arguments In order to receive program arguments your jjs invocation needs to use the -scripting flag and a double-dash to separate which arguments are for jjs and which are for the script itself:jjs -scripting print.js -- "This will print" #!/usr/bin/jjs var whatYouSaid = $ARG.length==0 ? "You did not say anything" : $ARG[0] print(whatYouSaid); Interoperability with Java libraries (including 3rd party dependencies) Another goal of Nashorn was to allow for quick scriptable prototypes, allowing access into Java types and any libraries. Resources operate in the context of the script (either in-line with the script or as separate threads) so if you open network sockets and your script terminates, those sockets will be released and available for your next run. Your code can access Java types the same as regular Java classes. The “import statements” are written somewhat differently to accommodate for language. There is a choice of two styles: For standard classes, just name the class: var ServerSocket = java.net.ServerSocket For arrays or other items, use Java.type: var ByteArray = Java.type("byte[]")You could technically do this for all. The same technique will allow your script to use Java types from any library or 3rd party component and quickly prototype items. Building a user interface One major difference between JavaScript inside and outside of a web browser is the availability of a DOM object for rendering views. When run outside of the browser, JavaScript has full control to construct the entire user interface with pre-fabricated UI controls, charts, or components. The example below is a variation from the Nashorn and JavaFX guide to show how items work together. Nashorn has a -fx flag to make the user interface components available. With the example script below, just specify: jjs -fx -scripting fx.js -- "My title" #!/usr/bin/jjs -fx var Button = javafx.scene.control.Button; var StackPane = javafx.scene.layout.StackPane; var Scene = javafx.scene.Scene; var clickCounter=0; $STAGE.title = $ARG.length>0 ? $ARG[0] : "You didn't provide a title"; var button = new Button(); button.text = "Say 'Hello World'"; button.onAction = myFunctionForButtonClicking; var root = new StackPane(); root.children.add(button); $STAGE.scene = new Scene(root, 300, 250); $STAGE.show(); function myFunctionForButtonClicking(){   var text = "Click Counter: " + clickCounter;   button.setText(text);   clickCounter++;   print(text); } For a more advanced post on using Nashorn to build a high-performing UI, see JavaFX with Nashorn Canvas example. Interoperable with frameworks like Node, Backbone, or Facebook React The major benefit of any language is the interoperability gained by people and systems that can read, write, and use it for interactions. Because Nashorn is built for the ECMAScript specification, developers familiar with JavaScript frameworks can write their code and then have system administrators deploy and monitor the applications the same as any other Java application. A number of projects are also running Node applications on Nashorn through Project Avatar and the supported modules. In addition to the previously mentioned Nashorn tutorial, Benjamin has also written a post about Using Backbone.js with Nashorn. To show the multi-language power of the Java Runtime, there is another interesting example that unites Facebook React and Clojure on JDK 8’s Nashorn. Summary Nashorn provides a simple and fast way of executing JavaScript applications and bridging between the best of each language. By making the full range of Java libraries to JavaScript applications, and the quick prototyping style of JavaScript to Java applications, developers are free to work as they see fit. Software Architects and System Administrators can take advantage of one runtime and leverage any work that they have done to tune, monitor, and certify their systems. Additional information is available within: The Nashorn Users’ Guide Java Magazine’s article "Next Generation JavaScript Engine for the JVM." The Nashorn team’s primary blog or a very helpful collection of Nashorn links.

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