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  • Error using to_char // to_timetamp

    - by pepersview
    Hello, I have a database in PostgreSQL and I'm developing an application in PHP using this database. The problem is that when I execute the following query I get a nice result in phpPgAdmin but in my PHP application I get an error. The query: SELECT t.t_name, t.t_firstname FROM teachers AS t WHERE t.id_teacher IN (SELECT id_teacher FROM teacher_course AS tcourse JOIN course_timetable AS coursetime ON tcourse.course = coursetime.course AND to_char(to_timestamp('2010-4-12', 'YYYY-MM-DD'),'FMD') = (coursetime.day +1)) AND t.id_teacher NOT IN (SELECT id_teacher FROM teachers_fill WHERE date = '2010-4-12') ORDER BY t.t_name ASC And this is the error in PHP operator does not exist: text = integer (to_timestamp('', 'YYYY-MM-DD'),'FMD') = (courset... ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. The purpose to solve this error is to use the ORIGINAL query in php with : $date = "2010"."-".$selected_month."-".$selected_day; SELECT t.t_name, t.t_firstname FROM teachers AS t WHERE t.id_teacher IN (SELECT id_teacher FROM teacher_course AS tcourse JOIN course_timetable AS coursetime ON tcourse.course = coursetime.course AND to_char(to_timestamp('$date', 'YYYY-MM-DD'),'FMD') = (coursetime.day +1)) AND t.id_teacher NOT IN (SELECT id_teacher FROM teachers_fill WHERE date = '$date') ORDER BY t.t_name ASC

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  • How to write these two queries for a simple data warehouse, using ANSI SQL?

    - by morpheous
    I am writing a simple data warehouse that will allow me to query the table to observe periodic (say weekly) changes in data, as well as changes in the change of the data (e.g. week to week change in the weekly sale amount). For the purposes of simplicity, I will present very simplified (almost trivialized) versions of the tables I am using here. The sales data table is a view and has the following structure: CREATE TABLE sales_data ( sales_time date NOT NULL, sales_amt double NOT NULL ) For the purpose of this question. I have left out other fields you would expect to see - like product_id, sales_person_id etc, etc, as they have no direct relevance to this question. AFAICT, the only fields that will be used in the query are the sales_time and the sales_amt fields (unless I am mistaken). I also have a date dimension table with the following structure: CREATE TABLE date_dimension ( id integer NOT NULL, datestamp date NOT NULL, day_part integer NOT NULL, week_part integer NOT NULL, month_part integer NOT NULL, qtr_part integer NOT NULL, year_part integer NOT NULL, ); which partition dates into reporting ranges. I need to write queries that will allow me to do the following: Return the change in week on week sales_amt for a specified period. For example the change between sales today and sales N days ago - where N is a positive integer (N == 7 in this case). Return the change in change of sales_amt for a specified period. For in (1). we calculated the week on week change. Now we want to know how that change is differs from the (week on week) change calculated last week. I am stuck however at this point, as SQL is my weakest skill. I would be grateful if an SQL master can explain how I can write these queries in a DB agnostic way (i.e. using ANSI SQL).

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  • Decimal To Octal Converter, last digit issue

    - by Srishan Supertramp
    I tried making a C program to convert a user entered decimal number to octal. I wrote the C code with my own logic without any research of how other users try to do it. It works fine for the number 601 and some other numbers but for most numbers it returns the octal equivalent with the last digit being 1 less than it should be. For 75 it returns 112 instead of 113. I realize using printf with %o gets the job done but it's kind of defeating the purpose of learning to program. Here's my code: #include <stdio.h> #include <math.h> /* converting decimal to octal */ int main() { int n,x,y,p,s; printf("Enter a decimal number "); scanf("%d",&x); s=0;p=0; while (x!=0) { y=x%8; s=s+y*pow(10,p); x=(x-y)/8; p=p+1; } printf("the octal equivalent is: %d\n",s); getch(); return 0; }

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  • Update PageTitle on Timer.Tick

    - by sohum
    I've got a page with a Timer that is being used as a trigger on an UpdatePanel. The page also contains a TabContainer and several TabPanels. Look at this question for more information. Basically, I've got an UpdatePanel as the element in each TabPanel's ContentTemplate, and the UpdatePanel is triggered by the Timer. My page displays data by reading a database on each tick. I've got the following code running on each Timer.Tick in my codebehind: protected void timeRefresher_Tick(object sender, EventArgs e) { UpdateLivePageTitle(); } The UpdateLivePageTitle() function reads the new information from the database and sets Page.Title accordingly. However, this information is of course not sent to the browser because there is no full page postback--only an async postback to the update panels. As a result, my page title is not being updated until the whole page is being posted back, which destroys the purpose of using UpdatePanels in the first place. I figure there would be a way to do this by using the document.title JS element and call that from within UpdateLivePageTitle(). But as of now, I haven't been able to figure out how to do this. I tried using the following in my UpdateLivePageTitle() function: string updatePageTitleScript = String.Format("document.title = '{0}'", newPageTitle); ToolkitScriptManager.RegisterStartupScript(this.Page, this.Page.GetType(), "UpdatePageTitle", updatePageTitleScript, true); But the result of this was that my TabContainer stopped rendering. I'm also not sure that would work with the async partial page postbacks, either. Any ideas? Thanks!

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  • How can I get git to work with a remote server?

    - by Adrienne
    I am the CM person for a small company that just started using Git. We have two Git repositories currently hosted on a Windows box that is our all-purpose Windows server. But, we just set up a dedicated server for our CM software on an Ubuntu Linux server named "Callisto". So I created a test Git repository on Callisto. I gave its directory all of the proper permissions recursively. I had the sysadmin create a login for me on Callisto, and I created a key to use for logging in via SSH. I set up my key to use a passphrase; I don't know if that could be contributing to my problems? Anyway, I know my SSH login works because I tested it through puTTY. But, even after hours of trials and head scratching, I can't get my Windows Git bash (mSysGit) to talk to Callisto for the purposes of pushing or pulling Callisto's git repository files. I keep getting "Fatal error. The remote end hung up unexpectedly." And I've even gotten the error that Git doesn't recognize the test repository on Callisto as a git repository. I read online that the "Fatal error...hung up unexpectedly" is usually a problem with the server connection or permissions. So what am I missing or overlooking here? And why doesn't a pull using the git:// protocol work, since that only uses read-only access? Group and public permissions for the git repository's directory on Callisto are set to read and execute, but not write. If anyone could help, I would be so grateful. Thank you.

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  • Clarification on Threads and Run Loops In Cocoa

    - by dubbeat
    I'm trying to learn about threading and I'm thoroughly confused. I'm sure all the answers are there in the apple docs but I just found it really hard to breakdown and digest. Maybe somebody could clear a thing or 2 up for me. 1)performSelectorOnMainThread Does the above simply register an event in the main run loop or is it somehow a new thread even though the method says "mainThread"? If the purpose of threads is to relieve processing on the main thread how does this help? 2) RunLoops Is it true that if I want to create a completely seperate thread I use "detachNewThreadSelector"? Does calling start on this initiate a default run loop for the thread that has been created? If so where do run loops come into it? 3) And Finally , I've seen examples using NSOperationQueue. Is it true to say that If you use performSelectorOnMainThread the threads are in a queue anyway so NSOperation is not needed? 4) Should I forget about all of this and just use the Grand Central Dispatch instead?

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  • How do you unit test new code that uses a bunch of classes that cannot be instantiated in a test har

    - by trendl
    I'm writing a messaging layer that should handle communication with a third party API. The API has a bunch of classes that cannot be easily (if at all) instantiated in a test harness. I decided to wrap each class that I need in my unit tests with an adapter/wrapper and expose the members I need through this adapter class. Often I need to expose the wrapped type as well which I do by exposing it as an object. I have also provided an interface for for each or the adapter classes to be able to use them with a mocking framework. This way I can substitute the classes in test for whatever I need. The downside is that I have a bunch of adapter classes that so far server no other reason but testing. For me this is a good reason by itself but others may find this not enough. Possibly, when I write an implementation for another third party vendor's API, I may be able to reuse much of my code and only provide the adapters specific to the vendor's API. However, this is a bit of a long shot and I'm not actually sure it will work. What do you think? Is this approach viable or am I writing unnecessary code that serves no real purpose? Let me say that I do want to write unit tests for my messaging layer and I do now know how to do it otherwise.

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  • Getting a "for each" loop in Java to run in different order everytime

    - by R Stokes
    Hi, Basically my problem is that I'm trying to write a method that finds a random path in a graph of strings, which takes as it's parameters a start string, an integer length and a Vector of strings that will store the path. I'm attempting to do this by first adding the starting string to our blank vector, recursing through its neighbors until the vector's length (not including the start node) is the same as the integer length specified in the parameters. I've provided my code so far here: public Vector<String> findRandomPathFrom(String n, int len, Vector<String> randomPath){ randomPath.add(n); if (randomPath.size() == len + 1) return randomPath; for (String m : this.neighbours(n)){ if (!randomPath.contains(m) && findRandomPathFrom(m, len, randomPath) != null) return randomPath; } path.setSize(path.size() - 1); return null; } It seems to be working fine, returning a path with exactly the number of strings specified after the given start string. However, for any given starting string it generates the EXACT same path everytime, which kind of defeats the purpose of it being a random path generator. I'm guessing this problem is related to my "for each" loop, which loops through all the neighbouring strings of your current string. It seems to just be going with the first string in the neighbours vector every single time. Can anyone help me fix this problem so that it will choose a random neighbour instead of going in order? tl;dr - Any way of getting a "for each" loop in java to process a collection in a random order as oppoosed to start-to-finsih? Thanks in advance

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  • CQRS without using others patterns

    - by John Smith
    I would like to explain CQRS to my team of developers. I just can't figure out how to explain it in the simplest way so they can implement the pattern rapidly without any others frameworks. I've read a lot of resources including video and articles but I don't find how to implement CQRS without using others patterns like a service Bus, event sourcing pattern, domain driven design. I know the purpose of these pattern but for the first step, I don't want them to think CQRS and theses patterns must be tied together. My first idea is to say that CQRS is about separating the read part and the write part. The read part is composed only of the UI project, and DAL project. Then the write part is composed of a typical multilayer architecture: UI/BLL/DAL. Then, does CQRS say we must also have two datastore ? What about the notion of commands which reveal the user's intention, is it also something part of CQRS or DDD ? Basically, how to implement CQRS without using others patterns. I concede it's also not that clear in my mind because I've used to work with NCQRS/DDD/Event Sourcing/ServiceBus in my personal project. Thanks

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  • UITableViewRowAnimationBottom doesn't work for last row

    - by GendoIkari
    I've come across a very similar question here: Inserting row to end of table with UITableViewRowAnimationBottom doesn't animate., though no answers have been given. His code was also a little different than mine. I have an extremely simple example, built from the Navigation application template. NSMutableArray *items; - (void)viewDidLoad { [super viewDidLoad]; items = [[NSMutableArray array] retain]; self.navigationItem.rightBarButtonItem = [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(addItem)] autorelease]; } - (void)addItem{ [items insertObject:@"new" atIndex:0]; [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:0 inSection:0]] withRowAnimation:UITableViewRowAnimationBottom]; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return items.count; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } cell.textLabel.text = [items objectAtIndex:indexPath.row]; return cell; } - (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath { if (editingStyle == UITableViewCellEditingStyleDelete) { [items removeObjectAtIndex:indexPath.row]; [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationBottom]; } } The problem is, when I either insert or delete the very last row in the table, the animation doesn't work at all; the row just appears or disappears instantly. This only happens with UITableViewRowAnimationBottom, but that's the animation that makes the most sense for creating or deleting table cells in this way. Is this a bug in Apple's framework? Or does it do this on purpose? Would it make sense to add an extra cell to the count, and then setup this cell so that it looks like it's not there at all, just to get around this behavior?

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  • How can I take advantage of IObservable/IObserver to get rid of my "god object"?

    - by Will
    In a system I'm currently working on, I have many components which are defined as interfaces and base classes. Each part of the system has some specific points where they interact with other parts of the system. For example, the data readying component readies some data which eventually needs to go to the data processing portion, the communications component needs to query different components for their status for relaying to the outside, etc. Currently, I glue these parts of the system together using a "god object", or an object with intimate knowledge of different parts of the system. It registers with events over here and shuttles the results to methods over there, creates a callback method here and returns the result of that method over there, and passes many requests through a multi-threaded queue for processing because it "knows" certain actions have to run on STA threads, etc. While its convenient, it concerns me that this one type knows so much about how everybody else in the system is designed. I'd much prefer a more generic hub that can be given instances which can expose events or methods or callbacks or that can consume these. I've been seeing more about the IObservable/IObserver features of the reactive framework and that are being rolled into .NET 4.0 (I believe). Can I leverage this pattern to help replace my "god object"? How should I go about doing this? Are there any resources for using this pattern for this specific purpose?

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  • Dimension Reduction in Categorical Data with missing values

    - by user227290
    I have a regression model in which the dependent variable is continuous but ninety percent of the independent variables are categorical(both ordered and unordered) and around thirty percent of the records have missing values(to make matters worse they are missing randomly without any pattern, that is, more that forty five percent of the data hava at least one missing value). There is no a priori theory to choose the specification of the model so one of the key tasks is dimension reduction before running the regression. While I am aware of several methods for dimension reduction for continuous variables I am not aware of a similar statical literature for categorical data (except, perhaps, as a part of correspondence analysis which is basically a variation of principal component analysis on frequency table). Let me also add that the dataset is of moderate size 500000 observations with 200 variables. I have two questions. Is there a good statistical reference out there for dimension reduction for categorical data along with robust imputation (I think the first issue is imputation and then dimension reduction)? This is linked to implementation of above problem. I have used R extensively earlier and tend to use transcan and impute function heavily for continuous variables and use a variation of tree method to impute categorical values. I have a working knowledge of Python so if something is nice out there for this purpose then I will use it. Any implementation pointers in python or R will be of great help. Thank you.

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  • How to deal with a Java serialized object whose package changed?

    - by Alex
    I have a Java class that is stored in an HttpSession object that's serialized and transfered between servers in a cluster environment. For the purpose of this explanation, lets call this class "Person". While in the process of improving the code, this class was moved from "com.acme.Person" to "com.acme.entity.Person". Internally, the class remains exactly the same (same fields, same methods, same everything). The problem is that we have two sets of servers running the old code and the new code at the same time. The servers with the old code have serialized HttpSession object and when the new code unserializes it, it throws a ClassNotFoundException because it can't find the old reference to com.acme.Person. At this point, it's easy to deal with this because we can just recreate the object using the new package. The problem then becomes that the HttpSession in the new servers, will serialize the object with the new reference to com.acme.entity.Person, and when this is unserialized in the servers running the old code, another exception will be thrown. At this point, we can't deal with this exception anymore. What's the best strategy to follow for this kind of cases? Is there a way to tell the new servers to serialize the object with the reference to the old package and unserialize references to the old package to the new one? How would we transition to using the new package and forgetting about the old one once all servers run the new code?

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  • Redirect requests only if the file is not found?

    - by ZenBlender
    I'm hoping there is a way to do this with mod_rewrite and Apache, but maybe there is another way to consider too. On my site, I have directories set up for re-skinned versions of the site for clients. If the web root is /home/blah/www, a client directory would be /home/blah/www/clients/abc. When you access the client directory via a web browser, I want it to use any requested files in the client directory if they exist. Otherwise, I want it to use the file in the web root. For example, let's say the client does not need their own index.html. Therefore, some code would determine that there is no index.html in /home/blah/www/clients/abc and will instead use the one in /home/blah/www. Keep in mind that I don't want to redirect the client to the web root at any time, I just want to use the web root's file with that name if the client directory has not specified its own copy. The web browser should still point to /clients/abc whether the file exists there or in the root. Likewise, if there is a request for news.html in the client directory and it DOES exist there, then just serve that file instead of the web root's news.html. The user's experience should be seamless. I need this to work for requests on any filename. If I need to, for example, add a new line to .htaccess for every file I might want to redirect, it rather defeats the purpose as there is too much maintenance needed, and a good chance for errors given the large number of files. In your examples, please indicate whether your code goes in the .htaccess file in the client directory, or the web root. Web root is preferred. Thanks for any suggestions! :)

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  • Building a survey to put in a WordPress website using Python/Django

    - by chiurox
    So I've been given a task to build a survey to get data regarding time slot preferences of prospective students for a particular course. I know there are really quick solutions to this like Google Forms, SurveyMonkey, but since it's not unusually hard, I want to implement the survey myself in a totally new language as an opportunity to get started with it and also be able to customize and provide dynamic info to the users who are voting. Although I have done some stuff in PHP, C++, javascript, etc, I'm pretty new to Python+Django framework but it's something I've been meaning to get into since a long time ago. Initially, what I want is to make a grid with the days of the week as columns and time-durations as rows. In each cell I want to provide users a way to choose how strong (high/medium/low) their preference for this particular day+time is. I also want to show how many "votes" have already been cast for this particular preference because this will influence a lot in their decisions and as a result make this process easier when we are going to define the classes. I'll probably store the data in MySQL. Could anyone point me to some really good Python+Django tutorials for my particular purpose? Does anyone think I'm wasting my time with this trivial task by choosing new tools and that I should just use something I already know (like PHP) or a free service or plugin for Wordpress? Thanks!

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  • Best way to carry & modify a variable through various instances and functions?

    - by bobsoap
    I'm looking for the "best practice" way to achieve a message / notification system. I'm using an OOP-based approach for the script and would like to do something along the lines of this: if(!$something) $messages->add('Something doesn\'t exist!'); The add() method in the messages class looks somewhat like this: class messages { public function add($new) { $messages = $THIS_IS_WHAT_IM_LOOKING_FOR; //array $messages[] = $new; $THIS_IS_WHAT_IM_LOOKING_FOR = $messages; } } In the end, there is a method in which reads out $messages and returns every message as nicely formatted HTML. So the questions is - what type of variable should I be using for $THIS_IS_WHAT_IM_LOOKING_FOR? I don't want to make this use the database. Querying the db every time just for some messages that occur at runtime and disappear after 5 seconds just seems like overkill. Using global constants for this is apparently worst practice, since constants are not meant to be variables that change over time. I don't even know if it would work. I don't want to always pass in and return the existing $messages array through the method every time I want to add a new message. I even tried using a session var for this, but that is obviously not suited for this purpose at all (it will always be 1 pageload too late). Any suggestions? Thanks!

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  • How come the Actionscript 3 ENTER_FRAME event is crazy nuts?

    - by nstory
    So, I've been toying around with Flash, browsing through the documentation, and all that, and noticed that the ENTER_FRAME event seems to defy my expectation of a deterministic universe. Take the following example: (new MovieClip()).addEventListener(Event.ENTER_FRAME, function(ev) {trace("Test");}); Notice this anonymous MovieClip is not added to the display hierarchy, and any reference to it is immediately lost. It will actually print "Test" once a frame until it is garbage collected. How insane is that? The behavior of this is actually determined by when the garbage collector feels like coming around in all its unpredictable insanity! Is there a better way to create intermittent failures? Seriously. My two theories are that either the DisplayObject class stores weak references to all its instances for the purpose of dispatching ENTER_FRAME events, or, and much wilder, the Flash player actually scans the heap each frame looking for ENTER_FRAME listeners to pull on. Can any hardened Actionscript developer clue me in on how this works? (And maybe a why - the - f**k they thought this was a good idea?)

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  • How to avoid geometric slowdown with large Linq transactions?

    - by Shaul
    I've written some really nice, funky libraries for use in LinqToSql. (Some day when I have time to think about it I might make it open source... :) ) Anyway, I'm not sure if this is related to my libraries or not, but I've discovered that when I have a large number of changed objects in one transaction, and then call DataContext.GetChangeSet(), things start getting reaalllly slooowwwww. When I break into the code, I find that my program is spinning its wheels doing an awful lot of Equals() comparisons between the objects in the change set. I can't guarantee this is true, but I suspect that if there are n objects in the change set, then the call to GetChangeSet() is causing every object to be compared to every other object for equivalence, i.e. at best (n^2-n)/2 calls to Equals()... Yes, of course I could commit each object separately, but that kinda defeats the purpose of transactions. And in the program I'm writing, I could have a batch job containing 100,000 separate items, that all need to be committed together. Around 5 billion comparisons there. So the question is: (1) is my assessment of the situation correct? Do you get this behavior in pure, textbook LinqToSql, or is this something my libraries are doing? And (2) is there a standard/reasonable workaround so that I can create my batch without making the program geometrically slower with every extra object in the change set?

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  • Display data FROM Sheet1 on Sheet2 based on conditional value

    - by Shawn
    Imagine a worksheet with 30 pieces of information, such as: A1= Start Date A2 = End Date A3 = Resource Name A4 = Cost .... A30 = Whatever B1 = 1/1/2010 B2 = 2/15/2010 B3 = Joe Smith B4 = $10,000.00 ... B30 = Blah Blah Now imagine a third column, C. The purpose of the third column is to determine WHICH report that row of data needs to appear in. C1 = Report 1 C2 = Report 1 and Report 2 C3 = Report 4 and Report 7 C4 = Report 1 and Report 5 ... C30 = Report 2 Each report is on Sheets 2, 3, 4, 5 and so on (depending on how many I decide to create). As you can see form my example above, some data may need to appear in multiple reports. For example, the data in Row 3 (Resource Name: Joe Smith) needs to appear in Report 4 and Report 7. That is to say, it needs to DYNAMICALLY appear on two additional worksheets. If I change the values in column C, then the reports need to update automatically. How can I create the worksheets which will serve as the reports such that they only diaplay the rows which have been "flagged" to be displayed in that report? Thanks!

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  • MySQL: Limit rows linked to each joined row

    - by SolidSnakeGTI
    Hello, Specifications: MySQL 4.1+ I've certain situation that requires certain result set from MySQL query, let's see the current query first & then ask my question: SELECT thread.dateline AS tdateline, post.dateline AS pdateline, MIN(post.dateline) FROM thread AS thread LEFT JOIN post AS post ON(thread.threadid = post.threadid) LEFT JOIN forum AS forum ON(thread.forumid = forum.forumid) WHERE post.postid != thread.firstpostid AND thread.open = 1 AND thread.visible = 1 AND thread.replycount >= 1 AND post.visible = 1 AND (forum.options & 1) AND (forum.options & 2) AND (forum.options & 4) AND forum.forumid IN(1,2,3) GROUP BY post.threadid ORDER BY tdateline DESC, pdateline ASC As you can see, mainly I need to select dateline of threads from 'thread' table, in addition to dateline of the second post of each thread, that's all under the conditions you see in the WHERE CLAUSE. Since each thread has many posts, and I need only one result per thread, I've used GROUP BY CLAUSE for that purpose. This query will return only one post's dateline with it's related unique thread. My questions are: How to limit returned threads per each forum!? Suppose I need only 5 threads -as a maximum- to be returned for each forum declared in the WHERE CLAUSE 'forum.forumid IN(1,2,3)', how can this be achieved. Is there any recommendations for optimizing this query (of course after solving the first point)? Notes: I prefer not to use sub-queries, but if it's the only solution available I'll accept it. Double queries not recommended. I'm sure there's a smart solution for this situation. Appreciated advice in advance :)

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  • Android Service setForeground While Display Sleeps

    - by c12
    I have a background Android Service that's purpose is to communicate with another device (non-phone) using a Bluetooth socket. Everything works fine except that the service gets stopped and restarted by the OS when the phone display is sleeping. This restart sometimes leaves a 15-20 minute gaps where there is no communication between the Service and the Bluetooth device and I need to be able to query the device every minute. Is startForeground the proper approach? Attempted to use: startForeground(int, Notification) //still see gaps when phone sleeps Service: public class ForegroundBluetoothService extends Service{ private boolean isStarted = false; @Override public void onDestroy() { super.onDestroy(); stop(); } /** * @see android.app.Service#onBind(android.content.Intent) */ @Override public IBinder onBind(Intent intent) { return null; } /** * @see android.app.Service#onStartCommand(android.content.Intent, int, int) */ @Override public int onStartCommand(Intent intent, int flags, int startId) { loadServiceInForeground(); return(START_STICKY); } private void loadServiceInForeground() { if (!isStarted) { isStarted=true; Notification notification = new Notification(R.drawable.icon, "Service is Running...", System.currentTimeMillis()); Intent notificationIntent = new Intent(this, MainScreen.class); PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0); notification.setLatestEventInfo(this, "Notification Title", "Service is Running...", pendingIntent); startForeground(12345, notification); try{ queryTheBluetoothDevice(); } catch(Exception ex){ ex.printStackTrace(); } } } private void stop() { if (isStarted) { isStarted=false; stopForeground(true); } } }

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  • Why is Excel's 'Evaluate' method a general expression evaluator?

    - by jtolle
    A few questions have come up recently involving the Application.Evaluate method callable from Excel VBA. The old XLM macro language also exposes an EVALUATE() function. Both can be quite useful. Does anyone know why the evaluator that is exposed can handle general expressions, though? My own hunch is that Excel needed to give people a way to get ranges from string addresses, and to get the value of named formulas, and just opening a portal to the expression evaluator was the easiest way. (The help for the VBA version does say its purpose it to "convert a Microsoft Excel name to an object or a value".) But of course you don't need the ability to evaluate arbitrary expressions just to do that. (That is, Excel could provide a Name.Evaluate method or something instead.) Application.Evaluate seems kind of...unfinished. It's full behavior isn't very well documented, and there are quite a few quirks and limitations (as described by Charles Williams here: http://www.decisionmodels.com/calcsecretsh.htm) with what is exposed. I suppose the answer could be simply "why not expose it?", but I'd be interested to know what design decisions led to this feature taking the form that it does. Failing that, I'd be interested to hear other hunches.

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  • Best way to build an application based on R?

    - by Prasad Chalasani
    I'm looking for suggestions on how to go about building an application that uses R for analytics, table generation, and plotting. What I have in mind is an application that: displays various data tables in different tabs, somewhat like in Excel, and the columns should be sortable by clicking. takes user input parameters in some dialog windows. displays plots dynamically (i.e. user-input-dependent) either in a tab or in a new pop-up window/frame Note that I am not talking about a general-purpose fron-end/GUI for exploring data with R (like say Rattle), but a specific application. Some questions I'd like to see addressed are: Is an entirely R-based approach even possible ( on Windows ) ? The following passage from the Rattle article in R-Journal intrigues me: It is interesting to note that the first implementation of Rattle actually used Python for implementing the callbacks and R for the statistics, using rpy. The release of RGtk2 allowed the interface el- ements of Rattle to be written directly in R so that Rattle is a fully R-based application If it's better to use another language for the GUI part, which language is best suited for this? I'm looking for a language where it's relatively "painless" to build the GUI, and that also integrates very well with R. From this StackOverflow question How should I do rapid GUI development for R and Octave methods (possibly with Python)? I see that Python + PyQt4 + QtDesigner + RPy2 seems to be the best combo. Is that the consensus ? Anyone have pointers to specific (open source) applications of the type I describe, as examples that I can learn from?

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  • Determing if an unordered vector<T> has all unique elements

    - by Hooked
    Profiling my cpu-bound code has suggested I that spend a long time checking to see if a container contains completely unique elements. Assuming that I have some large container of unsorted elements (with < and = defined), I have two ideas on how this might be done: The first using a set: template <class T> bool is_unique(vector<T> X) { set<T> Y(X.begin(), X.end()); return X.size() == Y.size(); } The second looping over the elements: template <class T> bool is_unique2(vector<T> X) { typename vector<T>::iterator i,j; for(i=X.begin();i!=X.end();++i) { for(j=i+1;j!=X.end();++j) { if(*i == *j) return 0; } } return 1; } I've tested them the best I can, and from what I can gather from reading the documentation about STL, the answer is (as usual), it depends. I think that in the first case, if all the elements are unique it is very quick, but if there is a large degeneracy the operation seems to take O(N^2) time. For the nested iterator approach the opposite seems to be true, it is lighting fast if X[0]==X[1] but takes (understandably) O(N^2) time if all the elements are unique. Is there a better way to do this, perhaps a STL algorithm built for this very purpose? If not, are there any suggestions eek out a bit more efficiency?

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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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