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  • Things I've noticed with DVCS

    - by Wes McClure
    Things I encourage: Frequent local commits This way you don't have to be bothered by changes others are making to the central repository while working on a handful of related tasks.  It's a good idea to try to work on one task at a time and commit all changes at partitioned stopping points.  A local commit doesn't have to build, just FYI, so a stopping point doesn't mean a build point nor a point that you can push centrally.  There should be several of these in any given day.  2 hours is a good indicator that you might not be leveraging the power of frequent local commits.  Once you have verified a set of changes works, save them away, otherwise run the risk of introducing bugs into it when working on the next task.  The notion of a task By task I mean a related set of changes that can be completed in a few hours or less.  In the same token don’t make your tasks so small that critically related changes aren’t grouped together.  Use your intuition and the rest of these principles and I think you will find what is comfortable for you. Partial commits Sometimes one task explodes or unknowingly encompasses other tasks, at this point, try to get to a stopping point on part of the work you are doing and commit it so you can get that out of the way to focus on the remainder.  This will often entail committing part of the work and continuing on the rest. Outstanding changes as a guide If you don't commit often it might mean you are not leveraging your version control history to help guide your work.  It's a great way to see what has changed and might be causing problems.  The longer you wait, the more that has changed and the harder it is to test/debug what your changes are doing! This is a reason why I am so picky about my VCS tools on the client side and why I talk a lot about the quality of a diff tool and the ability to integrate that with a simple view of everything that has changed.  This is why I love using TortoiseHg and SmartGit: they show changed files, a diff (or two way diff with SmartGit) of the current selected file and a commit message all in one window that I keep maximized on one monitor at all times. Throw away / stash commits There is extreme value in being able to throw away a commit (or stash it) that is getting out of hand.  If you do not commit often you will have to isolate the work you want to commit from the work you want to throw away, which is wasted productivity and highly prone to errors.  I find myself doing this about once a week, especially when doing exploratory re-factoring.  It's much easier if I can just revert all outstanding changes. Sync with the central repository daily The rest of us depend on your changes.  Don't let them sit on your computer longer than they have to.  Waiting increases the chances of merge conflict which just decreases productivity.  It also prohibits us from doing deploys when people say they are done but have not merged centrally.  This should be done daily!  Find a way to partition the work you are doing so that you can sync at least once daily. Things I discourage: Lots of partial commits right at the end of a series of changes If you notice lots of partial commits at the end of a set of changes, it's likely because you weren't frequently committing, nor were you watching for the size of the task expanding beyond a single commit.  Chances are this cost you productivity if you use your outstanding changes as a guide, since you would have an ever growing list of changes. Committing single files Committing single files means you waited too long and no longer understand all the changes involved.  It may mean there were overlapping changes in single files that cannot be isolated.  In either case, go back to the suggestions above to avoid this.  Committing frequently does not mean committing frequently right at the end of a day's work. It should be spaced out over the course of several tasks, not all at the end in a 5 minute window.

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  • Algorithm for tracking progress of controller method running in background

    - by SilentAssassin
    I am using Codeigniter framework for PHP on Windows platform. My problem is I am trying to track progress of a controller method running in background. The controller extracts data from the database(MySQL) then does some processing and then stores the results again in the database. The complete aforesaid process can be considered as a single task. A new task can be assigned while another task is running. The newly assigned task will be added in a queue. So if I can track progress of the controller, I can show status for each of these tasks. Like I can show "Pending" status for tasks in the queue, "In Progress" for tasks running and "Done" for tasks that are completed. Main Issue: Now first thing I need to find is an algorithm to track the progress of how much amount of execution the controller method has completed and that means tracking how much amount of method has completed execution. For instance, this PHP script tracks progress of array being counted. Here the current state and state after total execution are known so it is possible to track its progress. But I am not able to devise anything analogous to it in my case. Maybe what I am trying to achieve is programmtically not possible. If its not possible then suggest me a workaround or a completely new approach. If some details are pending you can mention them. Sorry for my ignorance this is my first post here. I welcome you to point out my mistakes. EDIT: Database outline: The URL(s) and keyword(s) are first entered by user which are stored in a database table called link_master and keyword_master respectively. Then keywords are extracted from all the links present in this table and compared with keywords entered by user and their frequency is calculated which is the final result. And the results are stored in another table called link_result. Now sub-links are extracted from the domain links and stored in a table called sub_link_master. Now again the keywords are extracted from these sub-links and the corresponding results are stored in a table called sub_link_result. The number of records cannot be defined beforehand as the number of links on any web page can be different. Only the cardinality of *link_result* table can be known which will be equal to multiplication of number of keyword(s) and URL(s) . I insert multiple records at a time using this resource. Controller outline: The controller extracts keywords from a web page and also extracts keywords from all the links present on that page. There is a method called crawlLink. I used Rolling Curl to extract keywords and web page content. It has callback function which I used for extracting keywords alongwith generating results and extracting valid sub-links. There is a insertResult method which stores results for links and sub-links in the respective tables. Yes, the processing depends on the number of records. The more the number of records, the more time it takes to execute: Consider this scenario: Number of Domain Links = 1 Number of Keywords = 3 Number of Domain Links Result generated = 3 (3 x 1 as described in the question) Number of Sub Links generated = 41 Number of Sub Links Result = 117 (41 x 3 = 123 but some links are not valid or searchable) Approximate time taken for above process to complete = 55 seconds. The above result is for a single link. I want to track the progress of the above results getting stored in database. When all results are stored, the task is complete. If results are getting stored, the task is In Progress. I am not clear how can I track this progress.

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  • Core Data @sum aggregate

    - by nasim
    I am getting an exception when I try to get @sum on a column in iPhone Core-Data application. My two models are following - Task model: @interface Task : NSManagedObject { } @property (nonatomic, retain) NSString * taskName; @property (nonatomic, retain) NSSet* completion; @end @interface Task (CoreDataGeneratedAccessors) - (void)addCompletionObject:(NSManagedObject *)value; - (void)removeCompletionObject:(NSManagedObject *)value; - (void)addCompletion:(NSSet *)value; - (void)removeCompletion:(NSSet *)value; @end Completion model: @interface Completion : NSManagedObject { } @property (nonatomic, retain) NSNumber * percentage; @property (nonatomic, retain) NSDate * time; @property (nonatomic, retain) Task * task; @end And here is the fetch: NSFetchRequest *request = [[NSFetchRequest alloc] init]; request.entity = [NSEntityDescription entityForName:@"Task" inManagedObjectContext:context]; NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"taskName" ascending:YES]; request.sortDescriptors = [NSArray arrayWithObject:sortDescriptor]; NSError *error; NSArray *results = [context executeFetchRequest:request error:&error]; NSArray *parents = [results valueForKeyPath:@"taskName"]; NSArray *children = [results valueForKeyPath:@"[email protected]"]; NSLog(@"%@ %@", parents, children); [request release]; [sortDescriptor release]; The exception is thrown at the fourth line from bottom. The thrown exception is: *** -[NSCFSet decimalValue]: unrecognized selector sent to instance 0x3b25a30 *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSCFSet decimalValue]: unrecognized selector sent to instance 0x3b25a30' I would very much appreciate any kind of help. Thanks.

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  • Java problem with multiple threads when executing a runnable jar file

    - by Spi1988
    I have developed a Java Swing application, which uses the SwingWorker class to perform some long running tasks. When the application is run from the IDE (Netbeans), I can start multiple long running tasks simultaneously without any problem. I created a runnable jar file for the application, in order to be able to run it from outside the IDE. The application when run from this jar file works well with the only exception that it doesn't allow me to start 2 long running tasks simultaneously. When I start the first task (assume it takes 2 minitues to complete), every thing works fine, the UI does not freeze (it never freezes). However, when I try to run another task (assume it takes just 10 seconds, therefore it should finish before the first task) while the first task has not yet completed, nothing seems to happen. In reality, the second task would have started, and also finished its processing, however its results are only displayed once the first task completes. I dunno why this is happening. Is there some restriction on the number of threads which could run simultaneously on the JVM? Are there any jvm arguments which i could try to solve this problem. I hope i explained my problem well. Thanks in advance, Peter Bartolo

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  • .Net Remoting: Serialize Object and implementation

    - by flogo
    Hi, In my scenario there is a client-side assembly that contains a class (Task). This class implements an interface (ITask) that is known on the server. I'm trying to send a Task object from client to server without copying the assembly of the client manually to the server. If I just serialize the task object, the server obviously complains about the missing assembly. I then tried to serialze typeof(Task).Assembly but could not derserialize it on the server. Next I tried to File.ReadAllBytes(typeof(Task).Assembly.Location) and saved it to a temporary file on the server, which threw an exception on Assembly.LoadFrom(@".\temporary.dll"); Why am I doing this? Java RMI has a neat feature to request the implementation of an object that is received through remoting but is stil "unkown" (this JVM doesn't have the *.class file). This can be used for a compute server that just knows the interface of a "task" containing a run() method and downloads the implementation of this method on demand. This way the server doesn't have to be changed for new tasks. I'm trying to achieve something like this in .Net.

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  • In threads, WaitForMultipleObjects never returns if set to INFINITE

    - by AKN
    Let say I have three thread handles HandleList[0] = hThread1; HandleList[1] = hThread2; HandleList[2] = hThread3; /*All the above are of type HANDLE*/ Before closing the application, I want the thread to get its task done. So I want to make app wait till thread completes. So I do, WaitForMultipleObjects(3, HandleList, TRUE, INFINITE ); By this I'm able to make the thread, complete its task. But control never move to next line after the call to WaitForMultileObjects irrespective of all thread completing its task. If I use, some seconds instead of INFINITE, it comes to next line after that many secs, irrspective of whether thread completes its task or not. WaitForMultipleObjects(3, HandleList, TRUE, 10000 ); My problem here is, I'm can't go for seconds, as I may not be sure whether the threads will complete its task with the given time. To list my problem in simple words, I want all my thread to finish the task, before I close my app. How can I achieve it using WaitForMultipleObjects API?

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  • Why would using a Temp table be faster than a nested query?

    - by Mongus Pong
    We are trying to optimise some of our queries. One query is doing the following: SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, INTO [#Gadget] FROM task t SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) as Client FROM [#Gadget] order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC DROP TABLE [#Gadget] (I have removed the complex subquery, cos I dont think its relevant other than to explain why this query has been done as a two stage process.) Now I would have thought it would be far more efficient to merge this down into a single query using subqueries as : SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) FROM ( SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, FROM task t ) as sub order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC This would give the optimiser better information to work out what was going on and avoid any temporary tables. It should be faster. But it turns out it is a lot slower. 8 seconds vs under 5 seconds. I cant work out why this would be the case as all my knowledge of databases imply that subqueries would always be faster than using temporary tables. Can anyone explain what could be going on!?!?

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  • where to store temporary data in MVC 2.0 project

    - by StuffHappens
    Hello! I'm starting to learn MVC 2.0 and I'm trying to create a site with a quiz: user is asked a question and given several options of answer. If he chooses the right answer he gets some points, if he doesn't, he looses them. I tried to do this the following way public class HomeController : Controller { private ITaskGenerator taskGenerator = new TaskGenerator(); private string correctAnswer; public ActionResult Index() { var task = taskGenerator .GenerateTask(); ViewData["Task"] = task.Task; ViewData["Options"] = task.Options; correctAnswer= task.CorrectAnswer; return View(); } public ActionResult Answer(string id) { if (id == correctAnswer) return View("Correct") return View("Incorrect"); } } But I have a problem: when user answers the cotroller class is recreated and I loose correct answer. So what is the best place to store correct answer? Should I create a static class for this purpose? Thanks for your help!

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  • Celery / Django Single Tasks being run multiple times

    - by felix001
    I'm facing an issue where I'm placing a task into the queue and it is being run multiple times. From the celery logs I can see that the same worker is running the task ... [2014-06-06 15:12:20,731: INFO/MainProcess] Received task: input.tasks.add_queue [2014-06-06 15:12:20,750: INFO/Worker-2] starting runner.. [2014-06-06 15:12:20,759: INFO/Worker-2] collection started [2014-06-06 15:13:32,828: INFO/Worker-2] collection complete [2014-06-06 15:13:32,836: INFO/Worker-2] generation of steps complete [2014-06-06 15:13:32,836: INFO/Worker-2] update created [2014-06-06 15:13:33,655: INFO/Worker-2] email sent [2014-06-06 15:13:33,656: INFO/Worker-2] update created [2014-06-06 15:13:34,420: INFO/Worker-2] email sent [2014-06-06 15:13:34,421: INFO/Worker-2] FINISH - Success However when I view the actual logs of the application it is showing 5-6 log lines for each step (??). Im using Django 1.6 with RabbitMQ. The method for placing into the queue is via placing a delay on a function. This function (task decorator is added( then calls a class which is run. Has anyone any idea on the best way to troubleshoot this ? Edit : As requested heres the code, views.py In my view im sending my data to the queue via ... from input.tasks import add_queue_project add_queue_project.delay(data) tasks.py from celery.decorators import task @task() def add_queue_project(data): """ run project """ logger = logging_setup(app="project") logger.info("starting project runner..") f = project_runner(data) f.main() class project_runner(): """ main project runner """ def __init__(self,data): self.data = data self.logger = logging_setup(app="project") def self.main(self): .... Code settings.py THIRD_PARTY_APPS = ( 'south', # Database migration helpers: 'crispy_forms', # Form layouts 'rest_framework', 'djcelery', ) import djcelery djcelery.setup_loader() BROKER_HOST = "127.0.0.1" BROKER_PORT = 5672 # default RabbitMQ listening port BROKER_USER = "test" BROKER_PASSWORD = "test" BROKER_VHOST = "test" CELERY_BACKEND = "amqp" # telling Celery to report the results back to RabbitMQ CELERY_RESULT_DBURI = "" CELERY_IMPORTS = ("input.tasks", ) celeryd The line im running is to start celery, python2.7 manage.py celeryd -l info Thanks,

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  • Which way is preferred when doing asynchronous WCF calls?

    - by Mikael Svenson
    When invoking a WCF service asynchronous there seems to be two ways it can be done. 1. public void One() { WcfClient client = new WcfClient(); client.BegindoSearch("input", ResultOne, null); } private void ResultOne(IAsyncResult ar) { WcfClient client = new WcfClient(); string data = client.EnddoSearch(ar); } 2. public void Two() { WcfClient client = new WcfClient(); client.doSearchCompleted += TwoCompleted; client.doSearchAsync("input"); } void TwoCompleted(object sender, doSearchCompletedEventArgs e) { string data = e.Result; } And with the new Task<T> class we have an easy third way by wrapping the synchronous operation in a task. 3. public void Three() { WcfClient client = new WcfClient(); var task = Task<string>.Factory.StartNew(() => client.doSearch("input")); string data = task.Result; } They all give you the ability to execute other code while you wait for the result, but I think Task<T> gives better control on what you execute before or after the result is retrieved. Are there any advantages or disadvantages to using one over the other? Or scenarios where one way of doing it is more preferable?

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  • Identifying a class which is extending an abstract class

    - by Simon A. Eugster
    Good Evening, I'm doing a major refactoring of http://wiki2xhtml.sourceforge.net/ to finally get better overview and maintainability. (I started the project when I decided to start programming, so – you get it, right? ;)) At the moment I wonder how to solve the problem I'll describe now: Every file will be put through several parsers (like one for links, one for tables, one for images, etc.): public class WikiLinks extends WikiTask { ... } public class WikiTables extends WikiTask { ... } The files will then be parsed about this way: public void parse() { if (!parse) return; WikiTask task = new WikiLinks(); do { task.parse(this); } while ((task = task.nextTask()) != null); } Sometimes I may want to use no parser at all (for files that only need to be copied), or only a chosen one (e.g. for testing purposes). So before running task.parse() I need to check whether this certain parser is actually necessary/desired. (Perhaps via Blacklist or Whitelist.) What would you suggest for comparing? An ID for each WikiTask (how to do?)? Comparing the task Object itself against a new instance of a WikiTask (overhead)?

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  • Adding to the DOM via Prototype works in Chrome but not Firefox?

    - by zaczap
    I've been working on some Javascript code to add rows to a table dynamically (a small task management system) and it works perfectly in Chrome but not in Firefox. Code in question: var task = new Element('tr', {id:arg}); task.innerHTML = "<td class='notes'>asd</td><td class='check'>*</td>"; //task.innerHTML = "<td class='notes'>&nbsp;</td><td class='check'><input type='checkbox' onclick=\"javascript:complete('"+task.id+"')\" /></td><td class='description'>asd</td><td class='start'>&nbsp;</td><td class='due'></td>"; $('tasks').insert(task); // the commented line above is what the code was originally that does work in chrome When I look at the HTML model in the Firefox debugger, all that is added is: <tr id="arg"><td>asd*</td></tr> Figuring that Chrome might be better at interpreting innerHTML into DOM elements than Firefox, I changed the code to make td elements and add them to my tr element but that didn't improve the situation at all.

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  • Logic in the db for maintaining a points system relationship?

    - by MarcusBooster
    I'm making a little web based game and need to determine where to put logic that checks the integrity of some underlying data in the sql database. Each user keeps track of points assigned to him, and points are awarded by various tasks. I keep a record of each task transaction to make sure they're not repeated, and to keep track of the value of the task at the time of completion, since an individual award level my fluctuate over time. My schema looks like this so far: create table player ( player_ID serial primary key, player_Points int not null default 0 ); create table task ( task_ID serial primary key, task_PointsAwarded int not null ); create table task_list ( player_ID int references player(player_ID), task_ID int references task(task_ID), when_completed timestamp default current_timestamp, point_value int not null, --not fk because task value may change later constraint pk_player_task_id primary key (player_ID, task_ID) ); So, the player.player_Points should be the total of all his cumulative task points in the task_list. Now where do I put the logic to enforce this? Should I do away with player.player_Points altogether and do queries every time I want to know the total score? Which seems wasteful since I'll be doing that query a lot over the course of a game. Or, put a trigger in the task_list that automatically updates the player.player_Points? Is that too much logic to have in the database and should just maintain this relationship in the application? Thanks.

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  • Exclude notes based on attribute wildcard in XSL node selection

    - by C A
    Using cruisecontrol for continuous integration, I have some annoyances with Weblogic Ant tasks and how they think that server debug information are warnings rather than debug, so are shown in my build report emails. The XML output from cruise is similar to: <cruisecontrol> <build> <target name="compile-xxx"> <task name="xxx" /> </target> <target name="xxx.weblogic"> <task name="wldeploy"> <message priority="warn">Message which isn't really a warning"</message> </task> </target> </build> </cruisecontrol> In the cruisecontrol XSL template the current selection for the task list is: <xsl:variable name="tasklist" select="/cruisecontrol/build//target/task"/> What I would like is something which selects the tasklist in the same way, but doesn't include any target nodes which have the attribute name="*weblogic" where * is a wildcard. I have tried <xsl:variable name="tasklist" select="/cruisecontrol/build//target[@name!='*weblogic']/task"/> but this doesn't seem to have worked. I'm not an expert with XSLT, and just want to get this fixed so I can carry on the real development of the project. Any help is much appreciated.

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  • Exclude nodes based on attribute wildcard in XSL node selection

    - by C A
    Using cruisecontrol for continuous integration, I have some annoyances with Weblogic Ant tasks and how they think that server debug information are warnings rather than debug, so are shown in my build report emails. The XML output from cruise is similar to: <cruisecontrol> <build> <target name="compile-xxx"> <task name="xxx" /> </target> <target name="xxx.weblogic"> <task name="wldeploy"> <message priority="warn">Message which isn't really a warning"</message> </task> </target> </build> </cruisecontrol> In the cruisecontrol XSL template the current selection for the task list is: <xsl:variable name="tasklist" select="/cruisecontrol/build//target/task"/> What I would like is something which selects the tasklist in the same way, but doesn't include any target nodes which have the attribute name="*weblogic" where * is a wildcard. I have tried <xsl:variable name="tasklist" select="/cruisecontrol/build//target[@name!='*weblogic']/task"/> but this doesn't seem to have worked. I'm not an expert with XSLT, and just want to get this fixed so I can carry on the real development of the project. Any help is much appreciated.

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  • Write out to text file using T-SQL

    - by sasfrog
    I am creating a basic data transfer task using TSQL where I am retrieving certain records from one database that are more recent than a given datetime value, and loading them into another database. This will happen periodically throughout the day. It's such a small task that SSIS seems like overkill - I want to just use a scheduled task which runs a .sql file. Where I need guidance is that I need to persist the datetime from the last run of this task, then use this to filter the records next time the task runs. My initial thought is to just store the datetime in a text file, and update (overwrite) it as part of the task each time it runs. I can read the file in without problems using T-SQL, but writing back out has got me stuck. I've seen plenty of examples which make use of a dynamically-built bcp command, which is then executed using xp_cmdshell. Trouble is, security on the server I'm deploying to precludes the use of xp_cmdshell. So, my question is, are there other ways to simply write a datetime value to a file using TSQL, or should I be thinking about a different approach? EDIT: happy to be corrected about SSIS being "overkill"...

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  • Loop through Array with conditional output based on key/value pair

    - by Daniel C
    I have an array with the following columns: Task Status I would like to print out a table that shows a list of the Tasks, but not the Status column. Instead, for Tasks where the Status = 0, I want to add a tag <del> to make the completed task be crossed out. Here's my current code: foreach ($row as $key => $val){ if ($key != 'Status') print "<td>$val</td>"; else if ($val == '0') print "<td><del>$val</del></td>"; } This seems to be correct, but when I print it out, it prints all the tasks with the <del> tag. So basically the "else" clause is being run every time. Here is the var_dump($row): array 'Task' => string 'Task A' (length=6) 'Status' => string '3' (length=1) array 'Task' => string 'Task B' (length=6) 'Status' => string '0' (length=1)

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  • Merging rows with uniqueness constraints

    - by Flambino
    I've got a little time-tracking web app (implemented in Rails 3.2.8 & MySQL). The app has several users who add their time to specific tasks, on a given date. The system is set up so a user can only have 1 time entry (i.e. row) per task per date. I.e. if you add time twice on the same task and date, it'll add time to the existing row, rather than create a new one. Now I'm looking to merge 2 tasks. In the simplest terms, merging task ID 2 into task ID 1 would take this time | user_id | task_id | date ------+----------+----------+----------- 10 | 1 | 1 | 2012-10-29 15 | 2 | 1 | 2012-10-29 10 | 1 | 2 | 2012-10-29 5 | 3 | 2 | 2012-10-29 and change it into this time | user_id | task_id | date ------+----------+----------+----------- 20 | 1 | 1 | 2012-10-29 <-- time values merged (summed) 15 | 2 | 1 | 2012-10-29 <-- no change 5 | 3 | 1 | 2012-10-29 <-- task_id changed (no merging necessary) I.e. merge by summing the time values, where the given user_id/date/task combo would conflict. I figure I can use a unique constraint to do a ON DUPLICATE KEY UPDATE ... if I do an insert for every task_id=2 entry. But that seems pretty inelegant. I've also tried to figure a way to first update all the rows in task 1 with the summed-up times, but I can't quite figure that one out. Any ideas?

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  • Silverlight 4 Training Kit

    - by ScottGu
    We recently released a new free Silverlight 4 Training Kit that walks you through building business applications with Silverlight 4.  You can browse the training kit online or alternatively download an entire offline version of the training kit.  The training material is structured on teaching how to use the new Silverlight 4 features to build an end to end business application. The training kit includes 8 modules, 25 videos, and several hands on labs. Below is a breakdown and links to all of the content. [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] Module 1: Introduction Click here to watch this module. In this video John Papa and Ian Griffiths discuss the key areas that the Building Business Applications with Silverlight 4 course focuses on. This module is the overview of the course and covers many key scenarios that are faced when building business applications, and how Silverlight can help address them. Module 2: WCF RIA Services Click here to explore this module. In this lab, you will create a web site for managing conferences that will be the basis for the other labs in this course. Don’t worry if you don’t complete a particular lab in the series – all lab manual instructions are accompanied by completed solutions, so you can either build your own solution from start to finish, or dive straight in at any point using the solutions provided as a starting point. In this lab you will learn how to set up WCF RIA Services, create bindings to the domain context, filter using the domain data source, and create domain service queries. Online Link Download Source Download Lab Document Videos Module 2.1 - WCF RIA Services Ian Griffiths sets up the Entity Framework and WCF RIA Services for the sample Event Manager application for the course. He covers how to set up the services, how the Domain Services work and the role that the DomainContext plays in the sample application. He also reviews the metadata classes and integrating the navigation framework. Module 2.2 – Using WCF RIA Services to Edit Entities Ian Griffiths discusses how he adds the ability to edit and create individual entities with the features built into WCF RIA Services into the sample Event Manager application. He covers data binding fundamentals, IQueryable, LINQ, the DomainDataSource, navigation to a single entity using the navigation framework, and how to use the Visual Studio designer to do much of the work . Module 2.3 – Showing Master/Details Records Using WCF RIA Services Ian Griffiths reviews how to display master/detail records for the sample Event Manager application using WCF RIA Services. He covers how to use the Include attribute to indicate which elements to serialize back to the client. Ian also demonstrates how to use the Data Sources window in the designer to add and bind controls to specific data elements. He wraps up by showing how to create custom services to the Domain Services. Module 3 – Authentication, Validation, MVVM, Commands, Implicit Styles and RichTextBox Click here to visit this module. This lab demonstrates how to build a login screen, integrate ASP.NET authentication, and perform validation on data elements. Model-View-ViewModel (MVVM) is introduced and used in this lab as a pattern to help separate the UI and business logic. You will also learn how to use implicit styling and the new RichTextBox control. Online Link Download Source Download Lab Document Videos Module 3.1 – Authentication Ian Griffiths covers how to integrate a login screen and authentication into the sample Event Manager application. Ian shows how to use the ASP.NET authentication and integrate it into WCF RIA Services and the Silverlight presentation layer. Module 3.2 – MVVM Ian Griffiths covers how to Model-View-ViewModel (MVVM) patterns into the sample Event Manager application. He discusses why MVVM exists, what separated presentation means, and why it is important. He shows how to connect the View to the ViewModel, why data binding is important in this symbiosis, and how everything fits together in the overall application. Module 3.3 –Validation Ian Griffiths discusses how validation of user input can be integrated into the sample Event Manager application. He demonstrates how to use the DataAnnotations, the INotifyDataErrorInfo interface, binding markup extensions, and WCF RIA Services in concert to achieve great validation in the sample application. He discusses how this technique allows for property level validation, entity level validation, and asynchronous server side validation. Module 3.4 – Implicit Styles Ian Griffiths discusses how why implicit styles are important and how they can be integrated into the sample Event Manager application. He shows how implicit styles defined in a resource dictionary can be applied to all elements of a particular kind throughout the application. Module 3.5 – RichTextBox Ian Griffiths discusses how the new RichTextBox control and it can be integrated into the sample Event Manager application. He demonstrates how the RichTextBox can provide editing for the event information and how it can display the rich text for selection and copying. Module 4 – User Profiles, Drop Targets, Webcam and Clipboard Click here to visit this module. This lab builds new features into the sample application to take the user's photo. It teaches you how to use the webcam to capture an image, use Silverlight as a drop target, and take advantage of programmatic access to the clipboard. Link Download Source Download Lab Document Videos Module 4.1 – Webcam Ian Griffiths demonstrates how the webcam adds value to the sample Event Manager application by capturing an image of the attendee. He discusses the VideoCaptureDevice, the CaptureDviceConfiguration, and the CaptureSource classes and how they allow audio and video to be captured so you can grab an image from the capture device and save it. Module 4.2 - Drag and Drop in Silverlight Ian Griffiths demonstrates how to capture and handle the Drop in the sample Event Manager application so the user can drag a photo from a file and drop it into the application. Ian reviews the AllowDrop property, the Drop event, how to access the file that can be dropped, and the other drag related events. He also reviews how to make this work across browsers and the challenges for this. Module 5 – Schedule Planner and Right Mouse Click Click here to visit this module. This lab builds on the application to allow grouping in the DataGrid and implement right mouse click features to add context menu support. Link Download Source Download Lab Document Videos Module 5.1 – Grouping and Binding Ian Griffiths demonstrates how to use the grouping features for data binding in the DataGrid and how it applies to the sample Event Manager application. He reviews the role of the CollectionViewSource in grouping, customizing the templates for headers, and how to work with grouping with ItemsControls. Module 5.2 – Layout Visual States Ian Griffiths demonstrates how to use the Fluid UI animation support for visual states in the ListBox control DataGrid and how it applies to the sample Event Manager application. He reviews the 3 visual states of BeforeLoaded, AfterLoaded, and BeforeUnloaded. Module 5.3 – Right Mouse Click Ian Griffiths demonstrates how to add support for handling the right mouse button click event to display a context menu for the Event Manager application. He demonstrates how to handle the event, show a custom context menu control, and integrate it into the scheduling portion of the application. Module 6 – Printing the Schedule Click here to visit this module. This lab teaches how to use the new printing features in Silverlight 4. The lab walks through the PrintDocument class and the ViewBox control, while showing how to print multiple pages of content using them. Link Download Source Download Lab Document Videos Module 6.1 – Printing and the Viewbox Ian Griffiths demonstrates how to add the ability to print the schedule to the sample Event Manager application. He walks through the importance of the PrintDocument class and its members. He also shows how to handle printing the visual tree and how the ViewBox control can help. Module 6.2 – Multi Page Printing Ian Griffiths expands on his printing discussion by showing how to handle printing multiple pages of content for the sample Event Manager application. He shows how to paginate the content and points out various tips to keep in mind when determining the printable area. Module 7 – Running the Event Dashboard Out of Browser Click here to visit this module. This lab builds a dashboard for the sample application while explaining the fundamentals of the out of browser features, how to handle authentication, displaying notifications (toasts), and how to use native integration to use COM Interop with Silverlight. Link Download Source Download Lab Document Videos Module 7.1 – Out of Browser Ian Griffiths discusses the role of an Out of Browser application for administrators to manage the events and users in the sample Event Manager application. He discusses several reasons why out of browser applications may better suit your needs including custom chrome, toasts, window placement, cross domain access, and file access. He demonstrates the basic technique to take your application and make it work out of browser using the tools. Module 7.2 – NotificationWindow (Toasts) for Elevated Trust Out of Browser Applications Ian Griffiths discusses the how toasts can be used in the sample Event Manager application to show information that may require the user's attention. Ian covers how to create a toast using the NotificationWindow, security implications, and how to make the toast appear as needed. Module 7.3 – Out of Browser Window Placement Ian Griffiths discusses the how to manage the window positioning when building an out of browser application, handling the windows state, and controlling and handling activation of the window. Module 7.4 – Out of Browser Elevated Trust Application Overview Ian Griffiths discusses the implications of creating trusted out of browser application for the Event Manager sample application. He reviews why you might want to use elevated trust, what features is opens to you, and how to take advantage of them. Topics Ian covers include the dynamic keyword in C# 4, the AutomationFactory class, the API to check if you are in a trusted application, and communicating with Excel. Module 8 – Advanced Out of Browser and MEF Click here to visit this module. This hands-on lab walks through the creation of a trusted out of browser application and the new functionality that comes with that. You will learn to use COM Automation, handle the window closing event, set custom window chrome, digitally sign your Silverlight out of browser trusted application, create a silent install option, and take advantage of MEF. Link Download Source Download Lab Document Videos Module 8.1 – Custom Window Chrome for Elevated Trust Out of Browser Applications Ian Griffiths discusses how to replace the standard operating system window chrome with customized chrome for an elevated trusted out of browser application. He covers how it is important to handle close, resize, minimize, and maximize events. Ian mentions that the tooling was not ready when he shot this video, but the good news is that the tooling now supports setting the custom chrome directly from the property page for the Silverlight application. Module 8.2 – Window Closing Event for Out of Browser Applications Ian Griffiths discusses the WindowClosing event and how to handle and optionally cancel the event. Module 8.3 – Silent Install of Out of Browser Applications Ian Griffiths discusses how to use the SLLauncher executable to install an out of browser application. He discusses the optional command line switches that can be set including how the emulate switch can help you emulate the install process. Ian also shows how to setup a shortcut for the application and tell the application where it should look for future updates online. Module 8.4 – Digitally Signing Out of Browser Application Ian Griffiths discusses how and why to digitally sign an out of browser application using the signtool program. He covers what trusted certificates are, the implications of signing (or not signing), and the effect on the user experience. Module 8.5 – The Value of MEF with Silverlight Ian Griffiths discusses what MEF is, how your application can benefit from it, and the fundamental features it puts at your disposal. He covers the 3 step import, export and compose process as well as how to dynamically import XAP files using MEF. Summary As you can probably tell from the long list above – this series contains a ton of great content, and hopefully provides a nice end-to-end walkthrough that helps explain how to take advantage of Silverlight 4 (and all its new features).  Hope this helps, Scott

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  • Keep Track of Your Tasks with toDoo

    - by Asian Angel
    A tasks list can be convenient but most times you can not include details for those tasks or have to have an online account to do so. If you want to keep your tasks list with you on your computer or laptop and be able to add plenty of details then you might want to look at toDoo. Note: Requires Adobe AIR (download link at bottom of article). toDoo in Action Once you have installed toDoo everything is rather straightforward for getting started. The first time that you start toDoo there will be a temporary “fill-in” for the “Subject & Details Areas”. Simply highlight over the temporary text and add your information. Notice that if desired you can easily set a custom date and time for your tasks right below the “Details Area”. Note: toDoo does not minimize to the “System Tray”. Once you have everything set all that you need to do is click on “add task”. Here was our first new task being viewed in the “toDoo Description Tab”. Time to add a second task…here you can see the drop-down calendar. You can scroll through and select a different month very easily…just click on the desired day and it will be automatically set. Adding our second task… If you need to edit any of the details for a particular task you can do so in the “Edit toDoo Tab”. This nice little app is convenient and easy to use. Conclusion ToDoo is a simple straightforward app that lets you keep track of your tasks list and relevant details without an online account (especially helpful if you are without a wireless connection at a given moment). If you are looking for more of a list approach that runs on your desktop, then check out our article on Doomi here. Links Download ToDoo at Softpedia Download ToDoo at Adobe Marketplace Download Adobe AIR Similar Articles Productive Geek Tips Turn Chrome’s New Tab Page into a Google Tasks PageMake To-Do Bar in Outlook 2007 Show Only Today’s TasksAdd a non-Google Tasks List to ChromeKeep Track of Homework Assignments with SoshikuTrack the Amount of Time You Spend Online in Firefox TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Download Videos from Hulu Pixels invade Manhattan Convert PDF files to ePub to read on your iPad Hide Your Confidential Files Inside Images Get Wildlife Photography Tips at BBC’s PhotoMasterClasses Mashpedia is a Real-time Encyclopedia

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  • ODI 12c - Aggregating Data

    - by David Allan
    This posting will look at the aggregation component that was introduced in ODI 12c. For many ETL tool users this shouldn't be a big surprise, its a little different than ODI 11g but for good reason. You can use this component for composing data with relational like operations such as sum, average and so forth. Also, Oracle SQL supports special functions called Analytic SQL functions, you can use a specially configured aggregation component or the expression component for these now in ODI 12c. In database systems an aggregate transformation is a transformation where the values of multiple rows are grouped together as input on certain criteria to form a single value of more significant meaning - that's exactly the purpose of the aggregate component. In the image below you can see the aggregate component in action within a mapping, for how this and a few other examples are built look at the ODI 12c Aggregation Viewlet here - the viewlet illustrates a simple aggregation being built and then some Oracle analytic SQL such as AVG(EMP.SAL) OVER (PARTITION BY EMP.DEPTNO) built using both the aggregate component and the expression component. In 11g you used to just write the aggregate expression directly on the target, this made life easy for some cases, but it wan't a very obvious gesture plus had other drawbacks with ordering of transformations (agg before join/lookup. after set and so forth) and supporting analytic SQL for example - there are a lot of postings from creative folks working around this in 11g - anything from customizing KMs, to bypassing aggregation analysis in the ODI code generator. The aggregate component has a few interesting aspects. 1. Firstly and foremost it defines the attributes projected from it - ODI automatically will perform the grouping all you do is define the aggregation expressions for those columns aggregated. In 12c you can control this automatic grouping behavior so that you get the code you desire, so you can indicate that an attribute should not be included in the group by, that's what I did in the analytic SQL example using the aggregate component. 2. The component has a few other properties of interest; it has a HAVING clause and a manual group by clause. The HAVING clause includes a predicate used to filter rows resulting from the GROUP BY clause. Because it acts on the results of the GROUP BY clause, aggregation functions can be used in the HAVING clause predicate, in 11g the filter was overloaded and used for both having clause and filter clause, this is no longer the case. If a filter is after an aggregate, it is after the aggregate (not sometimes after, sometimes having).  3. The manual group by clause let's you use special database grouping grammar if you need to. For example Oracle has a wealth of highly specialized grouping capabilities for data warehousing such as the CUBE function. If you want to use specialized functions like that you can manually define the code here. The example below shows the use of a manual group from an example in the Oracle database data warehousing guide where the SUM aggregate function is used along with the CUBE function in the group by clause. The SQL I am trying to generate looks like the following from the data warehousing guide; SELECT channel_desc, calendar_month_desc, countries.country_iso_code,       TO_CHAR(SUM(amount_sold), '9,999,999,999') SALES$ FROM sales, customers, times, channels, countries WHERE sales.time_id=times.time_id AND sales.cust_id=customers.cust_id AND   sales.channel_id= channels.channel_id  AND customers.country_id = countries.country_id  AND channels.channel_desc IN   ('Direct Sales', 'Internet') AND times.calendar_month_desc IN   ('2000-09', '2000-10') AND countries.country_iso_code IN ('GB', 'US') GROUP BY CUBE(channel_desc, calendar_month_desc, countries.country_iso_code); I can capture the source datastores, the filters and joins using ODI's dataset (or as a traditional flow) which enables us to incrementally design the mapping and the aggregate component for the sum and group by as follows; In the above mapping you can see the joins and filters declared in ODI's dataset, allowing you to capture the relationships of the datastores required in an entity-relationship style just like ODI 11g. The mix of ODI's declarative design and the common flow design provides for a familiar design experience. The example below illustrates flow design (basic arbitrary ordering) - a table load where only the employees who have maximum commission are loaded into a target. The maximum commission is retrieved from the bonus datastore and there is a look using employees as the driving table and only those with maximum commission projected. Hopefully this has given you a taster for some of the new capabilities provided by the aggregate component in ODI 12c. In summary, the actions should be much more consistent in behavior and more easily discoverable for users, the use of the components in a flow graph also supports arbitrary designs and the tool (rather than the interface designer) takes care of the realization using ODI's knowledge modules. Interested to know if a deep dive into each component is interesting for folks. Any thoughts? 

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  • ROracle support for TimesTen In-Memory Database

    - by Sam Drake
    Today's guest post comes from Jason Feldhaus, a Consulting Member of Technical Staff in the TimesTen Database organization at Oracle.  He shares with us a sample session using ROracle with the TimesTen In-Memory database.  Beginning in version 1.1-4, ROracle includes support for the Oracle Times Ten In-Memory Database, version 11.2.2. TimesTen is a relational database providing very fast and high throughput through its memory-centric architecture.  TimesTen is designed for low latency, high-volume data, and event and transaction management. A TimesTen database resides entirely in memory, so no disk I/O is required for transactions and query operations. TimesTen is used in applications requiring very fast and predictable response time, such as real-time financial services trading applications and large web applications. TimesTen can be used as the database of record or as a relational cache database to Oracle Database. ROracle provides an interface between R and the database, providing the rich functionality of the R statistical programming environment using the SQL query language. ROracle uses the OCI libraries to handle database connections, providing much better performance than standard ODBC.The latest ROracle enhancements include: Support for Oracle TimesTen In-Memory Database Support for Date-Time using R's POSIXct/POSIXlt data types RAW, BLOB and BFILE data type support Option to specify number of rows per fetch operation Option to prefetch LOB data Break support using Ctrl-C Statement caching support Times Ten 11.2.2 contains enhanced support for analytics workloads and complex queries: Analytic functions: AVG, SUM, COUNT, MAX, MIN, DENSE_RANK, RANK, ROW_NUMBER, FIRST_VALUE and LAST_VALUE Analytic clauses: OVER PARTITION BY and OVER ORDER BY Multidimensional grouping operators: Grouping clauses: GROUP BY CUBE, GROUP BY ROLLUP, GROUP BY GROUPING SETS Grouping functions: GROUP, GROUPING_ID, GROUP_ID WITH clause, which allows repeated references to a named subquery block Aggregate expressions over DISTINCT expressions General expressions that return a character string in the source or a pattern within the LIKE predicate Ability to order nulls first or last in a sort result (NULLS FIRST or NULLS LAST in the ORDER BY clause) Note: Some functionality is only available with Oracle Exalytics, refer to the TimesTen product licensing document for details. Connecting to TimesTen is easy with ROracle. Simply install and load the ROracle package and load the driver. > install.packages("ROracle") > library(ROracle) Loading required package: DBI > drv <- dbDriver("Oracle") Once the ROracle package is installed, create a database connection object and connect to a TimesTen direct driver DSN as the OS user. > conn <- dbConnect(drv, username ="", password="", dbname = "localhost/SampleDb_1122:timesten_direct") You have the option to report the server type - Oracle or TimesTen? > print (paste ("Server type =", dbGetInfo (conn)$serverType)) [1] "Server type = TimesTen IMDB" To create tables in the database using R data frame objects, use the function dbWriteTable. In the following example we write the built-in iris data frame to TimesTen. The iris data set is a small example data set containing 150 rows and 5 columns. We include it here not to highlight performance, but so users can easily run this example in their R session. > dbWriteTable (conn, "IRIS", iris, overwrite=TRUE, ora.number=FALSE) [1] TRUE Verify that the newly created IRIS table is available in the database. To list the available tables and table columns in the database, use dbListTables and dbListFields, respectively. > dbListTables (conn) [1] "IRIS" > dbListFields (conn, "IRIS") [1] "SEPAL.LENGTH" "SEPAL.WIDTH" "PETAL.LENGTH" "PETAL.WIDTH" "SPECIES" To retrieve a summary of the data from the database we need to save the results to a local object. The following call saves the results of the query as a local R object, iris.summary. The ROracle function dbGetQuery is used to execute an arbitrary SQL statement against the database. When connected to TimesTen, the SQL statement is processed completely within main memory for the fastest response time. > iris.summary <- dbGetQuery(conn, 'SELECT SPECIES, AVG ("SEPAL.LENGTH") AS AVG_SLENGTH, AVG ("SEPAL.WIDTH") AS AVG_SWIDTH, AVG ("PETAL.LENGTH") AS AVG_PLENGTH, AVG ("PETAL.WIDTH") AS AVG_PWIDTH FROM IRIS GROUP BY ROLLUP (SPECIES)') > iris.summary SPECIES AVG_SLENGTH AVG_SWIDTH AVG_PLENGTH AVG_PWIDTH 1 setosa 5.006000 3.428000 1.462 0.246000 2 versicolor 5.936000 2.770000 4.260 1.326000 3 virginica 6.588000 2.974000 5.552 2.026000 4 <NA> 5.843333 3.057333 3.758 1.199333 Finally, disconnect from the TimesTen Database. > dbCommit (conn) [1] TRUE > dbDisconnect (conn) [1] TRUE We encourage you download Oracle software for evaluation from the Oracle Technology Network. See these links for our software: Times Ten In-Memory Database,  ROracle.  As always, we welcome comments and questions on the TimesTen and  Oracle R technical forums.

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  • Why is my laptop so sluggish? Or Damn You Facebook and Twitter! Or All Hail Chrome!

    - by John Conwell
    In the past three weeks, I've noticed that my laptop (dual core 2.1GHz, 2Gb RAM) has become amazingly sluggish.  I only uses for communications and data lookup workflows, so the slowness was tolerable.  But today I finally got fed up with the suckyness and decided to get to the root of the problem (I do have strong performance roots after all). It actually didn't take all that long to figure it out.  About a year ago I converted to Google Chrome (away from FireFox).  One of the great tools Chrome has is a "Task Manager" tool, that gives you Windows Task Manager like details for all the tabs open in the browser (Shift + Esc).  Since every tab runs in its own process, its easy from Task Manager (both Windows or Chrome) to identify and kill a single performance offending tab.  This is unlike IE, where you only get aggregate data about all tabs open.  Anyway, I digress.  Today my laptop sucked.  Windows Task Manager told me that I had two memory hogging Chrome tabs, but couldn't tell me which web page those tabs are showing.  Enter Chrome Task Manager which tells you the page title, along with CPU, memory and network utilization of each tab.  Enter my amazement.  Turns out Facebook was using just shy of half a Gb of RAM.  Half a Gigabyte!  That's 512 Megabytes!524,288 Kilobytes! 536,870,912 Bytes!  Or 4,294,967,296 Bits!  In other words, that's a frackin boat load of memory.  Now consider that Facebook is running on pretty much 96.3% (statistics based on absolutely nothing) of every house hold desktop, laptop, netbook, and mobile device in America, that is pretty horrific! And I wasn't playing any Facebook games like FarmWars or MafiaVille.  I just had my normal, default home page up showing me who just had breakfast, or just got finished with their morning run. I'm sorry...let me say that again...HALF A GIG OF RAM!  That is just unforgivable. I can just see my mom calling me up:  Mom: "John...I think I need a new computer.  Mine is really slow these days" John: "What do you have running?" Mom: "Oh, just Facebook" John: "Ok, close Facebook and tell me how fast your computer feels" Mom: "Well...I don't know how fast it is.  All I do is use Facebook" John: "Ok Mom, I'll send you a new computer by Tuesday" Oh yea...and the other offending web page?  It was Twitter, using a quarter of a Gigabyte. God I love social networks!

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  • Interconnect nodes in a Java distributed infrastructure for tweet processing

    - by David Moreno García
    I'm working in a new version of an old project that I used to download and process user statuses from Twitter. The main problem of that project was its infrastructure. I used multiple instances of a java application (trackers) to download from Twitter given an specific task (basically terms to search for), connected with a central node (a web application) that had to process all tweets once per day and generate a new task for each trackers once each 15 minutes. The central node also had to monitor all trackers and enable/disable them under user petition. This, as I said, was too slow because I had multiple bottlenecks, so in this new version I want to improve the infrastructure and isolate all functionalities in specific nodes. I also need a good notification system to receive notifications for any node. So, in the next diagram I show the components that I'll need in this new version: As you can see, there are more nodes. Here are some notes about them: Dashboard: Controls trackers statuses and send a single task to each of them (under user request). The trackers will use this task until replaced with a new one (if done, not each 15 minutes like before). Search engine: I need to store all the tweets. They are firstly stored in a local database for each tracker but after that I'm thinking on using something like Elasticsearch to be able to do fast searches. Tweet processor: Just and isolated component with its own database (maybe something like the search engine to have fast access to info generated by the module). In the future more could be added. Application UI: A web application with a shared database with the Dashboard (mainly to store users information and preferences). Indeed, both could be merged into a single web. The main difference with the previous version of the project is that now they will be isolated and they will only show information and send requests. I will not do any heavy task in them (like process tweets as I did before). So, having this components, my main headache is how to structure all to not have to rewrite a lot of code every time I need to access any new data. Another headache is how can I interconnect nodes. I could use sockets but that is a pain in the ass. Maybe a REST layer? And finally, if all the nodes are isolated, how could I generate notifications for each user which info is only in the database used by the Application UI? I'm programming this using Java and Spring (at least I used them in the last version) but I have no problems with changing the language if I can take advantage of a tool/library/engine to make my life easier and have a better platform. Any comment will be appreciated.

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  • ROracle support for TimesTen In-Memory Database

    - by Sherry LaMonica
    Today's guest post comes from Jason Feldhaus, a Consulting Member of Technical Staff in the TimesTen Database organization at Oracle.  He shares with us a sample session using ROracle with the TimesTen In-Memory database.  Beginning in version 1.1-4, ROracle includes support for the Oracle Times Ten In-Memory Database, version 11.2.2. TimesTen is a relational database providing very fast and high throughput through its memory-centric architecture.  TimesTen is designed for low latency, high-volume data, and event and transaction management. A TimesTen database resides entirely in memory, so no disk I/O is required for transactions and query operations. TimesTen is used in applications requiring very fast and predictable response time, such as real-time financial services trading applications and large web applications. TimesTen can be used as the database of record or as a relational cache database to Oracle Database. ROracle provides an interface between R and the database, providing the rich functionality of the R statistical programming environment using the SQL query language. ROracle uses the OCI libraries to handle database connections, providing much better performance than standard ODBC.The latest ROracle enhancements include: Support for Oracle TimesTen In-Memory Database Support for Date-Time using R's POSIXct/POSIXlt data types RAW, BLOB and BFILE data type support Option to specify number of rows per fetch operation Option to prefetch LOB data Break support using Ctrl-C Statement caching support Times Ten 11.2.2 contains enhanced support for analytics workloads and complex queries: Analytic functions: AVG, SUM, COUNT, MAX, MIN, DENSE_RANK, RANK, ROW_NUMBER, FIRST_VALUE and LAST_VALUE Analytic clauses: OVER PARTITION BY and OVER ORDER BY Multidimensional grouping operators: Grouping clauses: GROUP BY CUBE, GROUP BY ROLLUP, GROUP BY GROUPING SETS Grouping functions: GROUP, GROUPING_ID, GROUP_ID WITH clause, which allows repeated references to a named subquery block Aggregate expressions over DISTINCT expressions General expressions that return a character string in the source or a pattern within the LIKE predicate Ability to order nulls first or last in a sort result (NULLS FIRST or NULLS LAST in the ORDER BY clause) Note: Some functionality is only available with Oracle Exalytics, refer to the TimesTen product licensing document for details. Connecting to TimesTen is easy with ROracle. Simply install and load the ROracle package and load the driver. > install.packages("ROracle") > library(ROracle) Loading required package: DBI > drv <- dbDriver("Oracle") Once the ROracle package is installed, create a database connection object and connect to a TimesTen direct driver DSN as the OS user. > conn <- dbConnect(drv, username ="", password="", dbname = "localhost/SampleDb_1122:timesten_direct") You have the option to report the server type - Oracle or TimesTen? > print (paste ("Server type =", dbGetInfo (conn)$serverType)) [1] "Server type = TimesTen IMDB" To create tables in the database using R data frame objects, use the function dbWriteTable. In the following example we write the built-in iris data frame to TimesTen. The iris data set is a small example data set containing 150 rows and 5 columns. We include it here not to highlight performance, but so users can easily run this example in their R session. > dbWriteTable (conn, "IRIS", iris, overwrite=TRUE, ora.number=FALSE) [1] TRUE Verify that the newly created IRIS table is available in the database. To list the available tables and table columns in the database, use dbListTables and dbListFields, respectively. > dbListTables (conn) [1] "IRIS" > dbListFields (conn, "IRIS") [1] "SEPAL.LENGTH" "SEPAL.WIDTH" "PETAL.LENGTH" "PETAL.WIDTH" "SPECIES" To retrieve a summary of the data from the database we need to save the results to a local object. The following call saves the results of the query as a local R object, iris.summary. The ROracle function dbGetQuery is used to execute an arbitrary SQL statement against the database. When connected to TimesTen, the SQL statement is processed completely within main memory for the fastest response time. > iris.summary <- dbGetQuery(conn, 'SELECT SPECIES, AVG ("SEPAL.LENGTH") AS AVG_SLENGTH, AVG ("SEPAL.WIDTH") AS AVG_SWIDTH, AVG ("PETAL.LENGTH") AS AVG_PLENGTH, AVG ("PETAL.WIDTH") AS AVG_PWIDTH FROM IRIS GROUP BY ROLLUP (SPECIES)') > iris.summary SPECIES AVG_SLENGTH AVG_SWIDTH AVG_PLENGTH AVG_PWIDTH 1 setosa 5.006000 3.428000 1.462 0.246000 2 versicolor 5.936000 2.770000 4.260 1.326000 3 virginica 6.588000 2.974000 5.552 2.026000 4 <NA> 5.843333 3.057333 3.758 1.199333 Finally, disconnect from the TimesTen Database. > dbCommit (conn) [1] TRUE > dbDisconnect (conn) [1] TRUE We encourage you download Oracle software for evaluation from the Oracle Technology Network. See these links for our software: Times Ten In-Memory Database,  ROracle.  As always, we welcome comments and questions on the TimesTen and  Oracle R technical forums.

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