Search Results

Search found 40741 results on 1630 pages for 'technology java se'.

Page 268/1630 | < Previous Page | 264 265 266 267 268 269 270 271 272 273 274 275  | Next Page >

  • Java: how does isDirectory and isFile work in File-class?

    - by HH
    $ javac GetAllDirs.java GetAllDirs.java:16: cannot find symbol symbol : variable checkFile location: class GetAllDirs System.out.println(checkFile.getName()); ^ 1 error $ cat GetAllDirs.java import java.util.*; import java.io.*; public class GetAllDirs { public void getAllDirs(File file) { if(file.isDirectory()){ System.out.println(file.getName()); File checkFile = new File(file.getCanonicalPath()); }else if(file.isFile()){ System.out.println(file.getName()); File checkFile = new File(file.getParent()); }else{ // checkFile should get Initialized at least HERE! File checkFile = file; } System.out.println(file.getName()); // WHY ERROR HERE: checkfile not found System.out.println(checkFile.getName()); } public static void main(String[] args) { GetAllDirs dirs = new GetAllDirs(); File current = new File("."); dirs.getAllDirs(current); } }

    Read the article

  • Java: how to initialize private final int value with if-else in constructor?

    - by HH
    $ javac InitInt.java InitInt.java:7: variable right might not have been initialized InitInt(){} ^ 1 error $ cat InitInt.java import java.util.*; import java.io.*; public class InitInt { private final int right; InitInt(){} public static void main(String[] args) { // I don't want to assign any value. // just initialize it, how? InitInt test = new InitInt(); System.out.println(test.getRight()); // later assiging a value } public int getRight(){return right;} } Initialization problem with Constructor, due to if-else -loop InitInt{ // Still the error, "may not be initialized" // How to initialise it, without removing if-else? if(snippetBuilder.length()>(charwisePos+25)){ right=charwisePos+25; }else{ right=snippetBuilder.length()-1; } }

    Read the article

  • how to run/compile java code from JTextArea at Runtime? ----urgent!!! college project

    - by Lokesh Kumar
    I have a JInternalFrame painted with a BufferedImage and contained in the JDesktopPane of a JFrame.I also have a JTextArea where i want to write some java code (function) that takes the current JInternalFrame's painted BufferedImage as an input and after doing some manipulation on this input it returns another manipulated BufferedImage that paints the JInternalFrame with new manipulated Image again!!. Manipulation java code of JTextArea:- public BufferedImage customOperation(BufferedImage CurrentInputImg) { Color colOld; Color colNew; BufferedImage manipulated=new BufferedImage(CurrentInputImg.getWidth(),CurrentInputImg.getHeight(),BufferedImage.TYPE_INT_ARGB); //make all Red pixels of current image black for(int i=0;i< CurrentInputImg.getWidth();i++) { for(int j=0;j< CurrentInputImg.getHeight(),j++) { colOld=new Color(CurrentInputImg.getRGB(i,j)); colNew=new Color(0,colOld.getGreen(),colOld.getBlue(),colOld.getAlpha()); manipulated.setRGB(i,j,colNew.getRGB()); } } return manipulated; } so,how can i run/compile this JTextArea java code at runtime and get a new manipulated image for painting on JInternalFrame???????   Here is my Main class: (This class is not actual one but i have created it for u for basic interfacing containing JTextArea,JInternalFrame,Apply Button) import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.event.*; import javax.swing.JInternalFrame; import javax.swing.JDesktopPane; import java.awt.image.*; import javax.imageio.*; import java.io.*; import java.io.File; import java.util.*; class MyCustomOperationSystem extends JFrame **{** public JInternalFrame ImageFrame; public BufferedImage CurrenFrameImage; public MyCustomOperationSystem() **{** setTitle("My Custom Image Operations"); setSize((int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),(int)Toolkit.getDefaultToolkit().getScreenSize().getHeight()); JDesktopPane desktop=new JDesktopPane(); desktop.setPreferredSize(new Dimension((int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),(int)Toolkit.getDefaultToolkit().getScreenSize().getHeight())); try{ CurrenFrameImage=ImageIO.read(new File("c:/Lokesh.png")); }catch(Exception exp) { System.out.println("Error in Loading Image"); } ImageFrame=new JInternalFrame("Image Frame",true,true,false,true); ImageFrame.setMinimumSize(new Dimension(CurrenFrameImage.getWidth()+10,CurrenFrameImage.getHeight()+10)); ImageFrame.getContentPane().add(CreateImagePanel()); ImageFrame.setLayer(1); ImageFrame.setLocation(100,100); ImageFrame.setVisible(true); desktop.setOpaque(true); desktop.setBackground(Color.darkGray); desktop.add(ImageFrame); this.getContentPane().setLayout(new BorderLayout()); this.getContentPane().add("Center",desktop); this.getContentPane().add("South",ControlPanel()); pack(); setVisible(true); **}** public JPanel CreateImagePanel(){ JPanel tempPanel=new JPanel(){ public void paintComponent(Graphics g) { g.drawImage(CurrenFrameImage,0,0,this); } }; tempPanel.setPreferredSize(new Dimension(CurrenFrameImage.getWidth(),CurrenFrameImage.getHeight())); return tempPanel; } public JPanel ControlPanel(){ JPanel controlPan=new JPanel(new FlowLayout(FlowLayout.LEFT)); JButton customOP=new JButton("Custom Operation"); customOP.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent evnt){ JFrame CodeFrame=new JFrame("Write your Code Here"); JTextArea codeArea=new JTextArea("Your Java Code Here",100,70); JScrollPane codeScrollPan=new JScrollPane(codeArea,ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS); CodeFrame.add(codeScrollPan); CodeFrame.setVisible(true); } }); JButton Apply=new JButton("Apply Code"); Apply.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent event){ // What should I do!!! Here!!!!!!!!!!!!!!! } }); controlPan.add(customOP); controlPan.add(Apply); return controlPan; } public static void main(String s[]) { new MyCustomOperationSystem(); } } Note: in above class JInternalFrame (ImageFrame) is not visible even i have declared it visible. so, ImageFrame is not visible while compiling and running above class. U have to identify this problem before running it.

    Read the article

  • What is the C# equivalent of java.util.regex?

    - by peter.murray.rust
    I am converting Java code to C# and need to replace the use of Java's regex. A typical use is import java.util.regex.Matcher; import java.util.regex.Pattern; //... String myString = "B12"; Pattern pattern = Pattern.compile("[A-Za-z](\\d+)"); Matcher matcher = Pattern.matcher(myString); String serial = (matcher.matches()) ? matcher.group(1) : null; which should extract a capture group from a matched target string. I'd be grateful for simple examples. EDIT: I have now added the C# equivalent of the code as an answer. EDIT: Here is a tutorial on the use of the actual expressions. EDIT: Here is a useful comparison of C# and Java (and Perl.)

    Read the article

  • An equivalent of -javaagent in C#? Or: ways to use a java framework in C#.

    - by Alix
    Hi everyone. This is probably something I should be able to figure out by myself, but I'm not having much luck so I figured I'd ask. The issue: I'm translating a system from java to C# and they use a java framework that I'd really like to use, since it takes care of the most complex parts of the system, which I would otherwise have to implement myself. I have the source code of this framework. I know there are several possibilities for using java libraries in C# (although I'm not familiar with any of them, so I'd appreciate suggestions). So far I've thought of using IKVM.NET to generate a .dll, but I'm not sure what to do next, because in java in order to run the framework with your code you're supposed to use the option -javaagent by adding -javaagent:bin/deuceAgent.jar (where deuceAgent is the framework) to your java command line. I don't know what the equivalent in C# would be once I have my .dll, or whether there's an equivalent at all. Any help? Thanks so much.

    Read the article

  • Correct way to (re)launch a Java application with hardware-dependent VM parameters?

    - by LowLevelAbstraction
    EDIT I don't want to use Java Web Start I've got a Java application that I'd like to run with different VM parameters depending on the amount of memory the system it is launched on has. For example if the machine has 1 GB of memory or less I'd like to pass "-Xmx200m" and "-Xmx400m" if it has 2 GB and "-Xmx800m" if it has 8 GB (these are just examples). Is there a portable way to do this? I've tried having a first tiny Java app (hence portable) that determines the amount of memory available and then launches a new Java app but I don't think this is very clean. As of now I've written Bash shell scripts that invoke the Java app with the correct parameters depending on the config but it only works on Linux on OS X. What is the correct way to solve this? Would application packager package ;) help ?

    Read the article

  • How do you access URL text following the # sign through Java?

    - by cmcculloh
    Using Java (.jsp or whatever) is there a way where I can send a request for this page: http://www.mystore.com/store/shelf.jsp?category=mens#page=2 and have the Java code parse the URL and see the #page=2 and respond accordingly? Basically, I'm looking for the Java code that allows me to access the characters following the hash tag. The reason I'm doing this is that I want to load subsequent pages via AJAX (on my shelf) and then allow the user to copy and paste the URL and send it to a friend. Without the ability of Java being able to read the characters following the hash tag I'm uncertain as to how I would manipulate the URL with Javascript in a way that the server would be able to also read without causing the page to re-load. I'm having trouble even figuring out how to access/see the entire URL (http://www.mystore.com/store/shelf.jsp?category=mens#page=2) from within my Java code...

    Read the article

  • In MATLAB can I convert a java boolean to a MATLAB logical?

    - by Adrian
    In MATLAB I'm using a couple of java routines I've written to interface with a MyQSL database. One routine returns a boolean value result <1x1 java.lang.Boolean> >> result result = true When I then use it in a conditional statement I get an error message. >> if result, disp('result is true') end ??? Conversion to logical from java.lang.Boolean is not possible. Is there a way to use the java boolean class as a MATLAB logical type? Or do I have to resort to returning integer values from my java routines?

    Read the article

  • Should class IOException in Java have been an unchecked RuntimeException?

    - by Derek Mahar
    Do you agree that the designers of Java class java.io.IOException should have made it an unchecked run-time exception derived from java.lang.RuntimeException instead of a checked exception derived only from java.lang.Exception? I think that class IOException should have been an unchecked exception because there is little that an application can do to resolve problems like file system errors. However, in When You Can't Throw An Exception, Elliotte Rusty Harold claims that most I/O errors are transient and so you can retry an I/O operation several times before giving up: For instance, an IOComparator might not take an I/O error lying down, but — because many I/O problems are transient — you can retry a few times, as shown in Listing 7: Is this generally the case? Can a Java application correct I/O errors or wait for the system to recover? If so, then it is reasonable for IOException to be checked, but if it is not the case, then IOException should be unchecked so that business logic can delegate handling of this exception to a separate system error handler.

    Read the article

  • What benefits can Java developer have from moving to a *NIX platform?

    - by dave-keiture
    Hi everyone, A friend of mine is a Java developer, who's using *NIX for ages. He claims that *NIX is for real Java geeks, whereas WIN is for dummies (and I'm one of them, according to him) and girls. When I ask him to argue his position, and explain, what's so good for Java developer on *NIX, he starts talking about console, wget, curl and grep. But sorry, wget and curl analogues exist for the WIN platform as well. As for the console - I'm using FAR Commander, and have access to the command line when I need. Moreover, even if I decide moving to *NIX, I will certainly use Netbeans or Eclipse on it, so there will be no big difference. Guys, who use Java on *NIX, could you please give me some real killer examples, when *NIX (any util or technique) dramatically increases Java development productivity (in the way the hints are given in "The Pragmatic Programmer"), or, which is also important, gives more fun from the process. Thanks in advance!

    Read the article

  • What benefits can Java developer have moving to a *NIX platform?

    - by dave-keiture
    Hi everyone, A friend of mine is a Java developer, who's using *NIX for ages. He claims that *NIX is for real Java geeks, whereas WIN is for dummies (and I'm one of them, according to him) and girls. When I ask him to argue his position, and explain, what's so good for Java developer on *NIX, he starts talking about console, wget, curl and grep. But sorry, wget and curl analogues exist for the WIN platform as well. As for the console - I'm using FAR Commander, and have access to the command line when I need. Moreover, even if I decide moving to *NIX, I will certainly use Netbeans or Eclipse there, so there will be no big difference. Guys, who use Java on *NIX, could you please give me a real killer examples, when *NIX (any util or technique) dramatically increases Java development productivity (in the way the hints are given in "The Pragmatic Programmer"), or, which is also important, gives more fun from the process. Thanks in advance!

    Read the article

  • How can I do block-oriented disk I/O with Java? Or similar for a B+ tree

    - by Sanoj
    I would like to implement an B+ tree in Java and try to optimize it for disk based I/O. Is there an API for accessing individual disk blocks from Java? or is there an API that can do similar block-oriented access that fits my purpose? I would like to create something like Tokyo Cabinet in 100% Java. Is there anyone that knows what Java only databases like JavaDB is using in the back-end for this? I know that there are probably other languages than Java that can do this better, but I do this in a learning purpose only.

    Read the article

  • Editing/Modifying a .java file programmatically? (not the .class file)

    - by Jay
    So, here is a piece of code using CodeModel that generates java code: JCodeModel cm = new JCodeModel(); JDefinedClass dc = cm._class("foo.Bar"); JMethod m = dc.method(0, int.class, "foo"); m.body()._return(JExpr.lit(5)); File f = new File("C:/target/classes"); f.mkdirs(); cm.build(f); This code generates a .java file: package foo; public class Bar { int foo() { return 5; } } However, I DO NOT want CodeModel to create a new java file for me. I do have a .java file already and would like to add a few lines of code to a method inside it. So, I would like the API to modify the java file directly/ create a modified copy of it. Is there a way to doing this?

    Read the article

  • How do you convert date taken from a bash script to milliseconds in java program?

    - by Matt Pascoe
    I am writing a piece of code in java that needs to take a time sent from a bash script and parse the time to milliseconds. When I check the millisecond conversion on the date everything is correct except for the month I have sent which is January instead of March. Here is the variable I create in the bash script, which later in the script I pass to the java program: TIME=`date +%m%d%Y_%H:%M:%S` Here is the java code which parses the time to milliseconds: String dt = "${scriptstart}"; java.text.SimpleDateFormat scriptStart = new java.text.SimpleDateFormat("MMDDyyyy_HH:mm:ss"); long start = scriptStart.parse(dt).getTime(); The goal of this statement is to find the elapsed time between the start of the script and the current system time. To troubleshoot this I printed out the two: System Time = 1269898069496 (converted = Mon Mar 29 2010 16:27:49 GMT-0500 (Central Daylight Time)) Script Start = 03292010_16:27:45 Script Start in Milli = 1264804065000 (Converted = Fri Jan 29 2010 16:27:45 GMT-0600 (Central Standard Time))

    Read the article

  • How to get the field name of a java (weak) reference pointing to an object in an other class?

    - by Tom
    Imagine I have the following situation: Test1.java import java.lang.ref.WeakReference; public class Test1 { public WeakReference fieldName; public init() { fieldName = new WeakReference(this); Test2.setWeakRef(fieldName); } } Test2.java import java.lang.ref.WeakReference; public class Test2 { public static setWeakRef(WeakReference weakRef) { //at this point I got weakRef in an other class.. now, how do I get the field name this reference was created with? So that it returns exactly "fieldName", because that's the name I gave it in Test1.java? } } At the location of the comment I received the weak reference created in an other class. How would I retreive the field name that this weak reference was created with, in this case "fieldName"? Thanks in advance.

    Read the article

  • In Java how instance of and type cast(i.e (ClassName)) works on proxy object ?

    - by learner
    Java generates a proxy class for a given interface and provides the instance of the proxy class. But when we type cast the proxy object to our specific Object, how java handles this internally? Is this treated as special scenario? For example I have class 'OriginalClass' and it implements 'OriginalInterface', when I create proxy object by passing 'OriginalInterface' interface java created proxy class 'ProxyClass' using methods in the provided interface and provides object of this class(i.e ProxyClass). If my understanding is correct then can you please answer following queries 1) When I type cast object of ProxyClass to my class OriginalClass this works, but how java is allowing this? Same in case of instace of? 2) As my knowledge java creates a proxy class only with the methods, but what happen when I try to access attributes on this object? 3) Only interface methods are getting implemented in Proxy, but what happens when I try to access a method which not in interface and only mentioned in the class? Thanks, Student

    Read the article

  • What features of Scala cannot be translated to Java?

    - by Paul
    The Scala compiler compiles direct to Java byte code (or .NET CIL). Some of the features of Scala could be re-done in Java straightforwardly (e.g. simple for comprehensions, classes, translating anonymous/inner functionc etc). What are the features that cannot be translated that way? That is presumably mostly of academic interest. More usefully, perhaps, what are the key features or idioms of Scala that YOU use that cannot be easily represented in Java? Are there any the other way about? Things that can be done straightforwardly in Java that have no straightforward equivalent in Scala? Idioms in Java that don't translate?

    Read the article

  • Aside from performance concerns, is Java still chosen over Groovy/JRuby etc.?

    - by yar
    [This is an empirical question about the state-of-the-art: I am NOT asking if Java is cooler or less cool than the dynamic languages that work in the JVM.] Aside from cases where performance is a main decision factor, do companies/developers still willingly chose Java over Groovy, JRuby or JPython? Personal Note: The reason I am asking is that, while I do some subset of my professional work in Ruby (not JRuby, for now), in my personal projects I use Java. While I have written non-trivial apps in Groovy, I prefer Java, but I wonder if I should just get over it and do everything in Groovy. I like Java because I feel that static typing saves me time and aids refactoring. (No, I am not familiar with Scala.) However, I feel that this very empirical, on-topic programming question may inform my decision.

    Read the article

  • How much Java should I have learnt before trying Android programming?

    - by Sidney Yin
    Hi - I have been seeking beginner learning books in Android, and of course found out that I should learn Java first. So I began studying Java and now I am quite comfortable with objects, classes, inheritance, interfaces, and just moved onto Layouts in Swing as well as Swing Features. But I am starting to wonder.... do I know enough about Java now? Can I start programming Android yet? Of course I can keep going in Java, but have been itching to begin programming Android apps. Any definitive answer here about how much Java I need to know before Android? Thanks so much!

    Read the article

  • Need help with this question: Write Java code which reads numbers from the keyboard.....

    - by Chris
    Write Java code which reads numbers from the keyboard until zero is entered. Only the positive numbers entered are to be added to a variable-sized collection. This is what I have so far: import java.lang.*; import java.util.*; import java.io.*; import java.net.*; public class Demo1App extends Object { public static void main(String[] argStrings) throws Exception { ArrayList myArrayList = new ArrayList(); Scanner input = new Scanner(System.in); System.out.println ("NUMBERS:"); while (int input > 0) { myArrayList.add(input); } while (int input < 0) { System.out.println ("ENTER NUMBERS GREATER THAN 0!"); } } } This code doesn't work, I'm not sure why but any help with it would be appreciated.

    Read the article

  • ODBC in SSIS 2012

    - by jamiet
    In August 2011 the SQL Server client team published a blog post entitled Microsoft is Aligning with ODBC for Native Relational Data Access in which they basically said "OLE DB is the past, ODBC is the future. Deal with it.". From that blog post:We encourage you to adopt ODBC in the development of your new and future versions of your application. You don’t need to change your existing applications using OLE DB, as they will continue to be supported on Denali throughout its lifecycle. While this gives you a large window of opportunity for changing your applications before the deprecation goes into effect, you may want to consider migrating those applications to ODBC as a part of your future roadmap.I recently undertook a project using SSIS2012 and heeded that advice by opting to use ODBC Connection Managers rather than OLE DB Connection Managers. Unfortunately my finding was that the ODBC Connection Manager is not yet ready for primetime use in SSIS 2012. The main issue I found was that you can't populate an Object variable with a recordset when using an Execute SQL Task connecting to an ODBC data source; any attempt to do so will result in an error:"Disconnected recordsets are not available from ODBC connections." I have filed a bug on Connect at ODBC Connection Manager does not have same funcitonality as OLE DB. For this reason I strongly recommend that you don't make the move to ODBC Connection Managers in SSIS just yet - best to wait for the next version of SSIS before doing that.I found another couple of issues with the ODBC Connection Manager that are worth keeping in mind:It doesn't recognise System Data Source Names (DSNs), only User DSNs (bug filed at ODBC System DSNs are not available in the ODBC Connection Manager)  UPDATE: According to a comment on that Connect item this may only be a problem on 64bit.In the OLE DB Connection Manager parameter ordinals are 0-based, in the ODBC Connection Manager they are 1-based (oh I just can't wait for the upgrade mess that ensues from this one!!!)You have been warned!@jamiet

    Read the article

  • SQL Server Configuration timeouts - and a workaround [SSIS]

    - by jamiet
    Ever since I started writing SSIS packages back in 2004 I have opted to store configurations in .dtsConfig (.i.e. XML) files rather than in a SQL Server table (aka SQL Server Configurations) however recently I inherited some packages that used SQL Server Configurations and thus had to immerse myself in their murky little world. To all the people that have ever gone onto the SSIS forum and asked questions about ambiguous behaviour of SQL Server Configurations I now say this... I feel your pain! The biggest problem I have had was in dealing with the change to the order in which configurations get applied that came about in SSIS 2008. Those changes are detailed on MSDN at SSIS Package Configurations however the pertinent bits are: As the utility loads and runs the package, events occur in the following order: The dtexec utility loads the package. The utility applies the configurations that were specified in the package at design time and in the order that is specified in the package. (The one exception to this is the Parent Package Variables configurations. The utility applies these configurations only once and later in the process.) The utility then applies any options that you specified on the command line. The utility then reloads the configurations that were specified in the package at design time and in the order specified in the package. (Again, the exception to this rule is the Parent Package Variables configurations). The utility uses any command-line options that were specified to reload the configurations. Therefore, different values might be reloaded from a different location. The utility applies the Parent Package Variable configurations. The utility runs the package. To understand how these steps differ from SSIS 2005 I recommend reading Doug Laudenschlager’s blog post Understand how SSIS package configurations are applied. The very nature of SQL Server Configurations means that the Connection String for the database holding the configuration values needs to be supplied from the command-line. Typically then the call to execute your package resembles this: dtexec /FILE Package.dtsx /SET "\Package.Connections[SSISConfigurations].Properties[ConnectionString]";"\"Data Source=SomeServer;Initial Catalog=SomeDB;Integrated Security=SSPI;\"", The problem then is that, as per the steps above, the package will (1) attempt to apply all configurations using the Connection String stored in the package for the "SSISConfigurations" Connection Manager before then (2) applying the Connection String from the command-line and then (3) apply the same configurations all over again. In the packages that I inherited that first attempt to apply the configurations would timeout (not unexpected); I had 8 SQL Server Configurations in the package and thus the package was waiting for 2 minutes until all the Configurations timed out (i.e. 15seconds per Configuration) - in a package that only executes for ~8seconds when it gets to do its actual work a delay of 2minutes was simply unacceptable. We had three options in how to deal with this: Get rid of the use of SQL Server configurations and use .dtsConfig files instead Edit the packages when they get deployed Change the timeout on the "SSISConfigurations" Connection Manager #1 was my preferred choice but, for reasons I explain below*, wasn't an option in this particular instance. #2 was discounted out of hand because it negates the point of using Configurations in the first place. This left us with #3 - change the timeout on the Connection Manager. This is done by going into the properties of the Connection Manager, opening the "All" tab and changing the Connect Timeout property to some suitable value (in the screenshot below I chose 2 seconds). This change meant that the attempts to apply the SQL Server configurations timed out in 16 seconds rather than two minutes; clearly this isn't an optimum solution but its certainly better than it was. So there you have it - if you are having problems with SQL Server configuration timeouts within SSIS try changing the timeout of the Connection Manager. Better still - don't bother using SQL Server Configuration in the first place. Even better - install RC0 of SQL Server 2012 to start leveraging SSIS parameters and leave the nasty old world of configurations behind you. @Jamiet * Basically, we are leveraging a SSIS execution/logging framework in which the client had invested a lot of resources and SQL Server Configurations are an integral part of that.

    Read the article

  • Microsoft 2010 Product Tour

    - by dmccollough
    Randy Walker, Co-Founder of the Northwest Arkansas .Net User Group and Microsoft MVP has arranged for a couple of Microsoft experts, Sarika Calla Team Lead on the IDE Team and Kevin Halverson to give presentations on newly released Visual Studio 2010.   June 1 – Bentonville, Arkansas Wal-Mart .Net User Group June 1 – Rogers, Arkansas Northwest Arkansas SQL Server User Group (lunch meeting) June 1 – Springdale, Arkansas Tyson devLoop June 1 – Fayetteville, Arkansas Northwest Arkansas .Net User Group June 2 – Fort Smith, Arkansas Datatronics June 2 – Little Rock, Arkansas Little Rock .Net User Group June 3 – Fort Worth, Texas Fort Worth .Net User Group   Please contact Randy Walker with questions at [email protected].

    Read the article

  • SSIS code smell – Unused columns in the dataflow

    - by jamiet
    A code smell is defined on Wikipedia as being a “symptom in the source code of a program that possibly indicates a deeper problem”. It’s a term commonly used by our code-writing brethren to describe sub-optimal code but I think the term can be applied equally well to SSIS packages too as I shall now explain One of my pet hates about SSIS development is packages that throw warnings of the form: The output column "ColumnName" (1358) on output "OLE DB Source Output" (1289) and component "OLE_SRC Name" (1279) is not subsequently used in the Data Flow task. Removing this unused output column can increase Data Flow task performance.  The warning is fairly self-explanatory – any column that appears in the data flow but doesn’t get used will throw this warning when the data flow is executed. Its not the negligible performance degradation that they cause that bothers me though, it’s the clutter that they cause in your log file/table. Take a look at the following screenshot if you don’t believe me: There are 231409 such warnings in the system that I took this screenshot from, that is 231409 log records that should not be there. The most infuriating thing about this warning is that it is so easily avoidable; eliminating such columns is a very quick and easy thing to do in the SSIS Designer. The only problem I see is that the warnings don’t occur until you execute the package – it would be preferable for the designer to have an unobtrusive way of informing you of them as well. Anyway, I digress… I consider such warnings to be a code smell because, to me, they’re symptomatic of a lack of due care and attention; a lack of developer discipline if you will. What other code smells can you think of when building SSIS packages? If I get a good list in the comments maybe I’ll compile them into a later blog post. @Jamiet Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

    Read the article

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

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

    Read the article

< Previous Page | 264 265 266 267 268 269 270 271 272 273 274 275  | Next Page >