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• Is there a way to efficiently yield every file in a directory containing millions of files?

  - by Josh Smeaton

  I'm aware of os.listdir, but as far as I can gather, that gets all the filenames in a directory into memory, and then returns the list. What I want, is a way to yield a filename, work on it, and then yield the next one, without reading them all into memory. Is there any way to do this? I worry about the case where filenames change, new files are added, and files are deleted using such a method. Some iterators prevent you from modifying the collection during iteration, essentially by taking a snapshot of the state of the collection at the beginning, and comparing that state on each move operation. If there is an iterator capable of yielding filenames from a path, does it raise an error if there are filesystem changes (add, remove, rename files within the iterated directory) which modify the collection? There could potentially be a few cases that could cause the iterator to fail, and it all depends on how the iterator maintains state. Using S.Lotts example: filea.txt fileb.txt filec.txt Iterator yields filea.txt. During processing, filea.txt is renamed to filey.txt and fileb.txt is renamed to filez.txt. When the iterator attempts to get the next file, if it were to use the filename filea.txt to find it's current position in order to find the next file and filea.txt is not there, what would happen? It may not be able to recover it's position in the collection. Similarly, if the iterator were to fetch fileb.txt when yielding filea.txt, it could look up the position of fileb.txt, fail, and produce an error. If the iterator instead was able to somehow maintain an index dir.get_file(0), then maintaining positional state would not be affected, but some files could be missed, as their indexes could be moved to an index 'behind' the iterator. This is all theoretical of course, since there appears to be no built-in (python) way of iterating over the files in a directory. There are some great answers below, however, that solve the problem by using queues and notifications. Edit: The OS of concern is Redhat. My use case is this: Process A is continuously writing files to a storage location. Process B (the one I'm writing), will be iterating over these files, doing some processing based on the filename, and moving the files to another location. Edit: Definition of valid: Adjective 1. Well grounded or justifiable, pertinent. (Sorry S.Lott, I couldn't resist). I've edited the paragraph in question above.

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• Is it possible to create a throttle function that can take in as parameters another function (that also has parameters), and the time delay

  - by Stan Quinn

  So I've already written a function that works (based on underscores throttle) for functions that don't take in a parameter, but I'd like to make it generic enough to pass in a function with a variable number of parameters. Here's what I have: (function () { var lastTime = new Date().getTime(); function foo() { var newTime = new Date().getTime(); var gap = newTime - lastTime; // Travels up scope chain to use parents lastTime. Function has access to variables declared in the same scope console.log('foo called, gap:' + gap); lastTime = newTime; // Updates lastTime //console.log(x); //x++; } var throttle = function(func, wait) { var result; var timeout = null; // flag updated through closure var previous = 0; // time last run updated through closure return function() { //func, wait, timeout, previous available through scope var now = new Date().getTime(); var remaining = wait - (now - previous); if (remaining <= 0) { clearTimeout(timeout); timeout = null; previous = now; result = func.apply(this, arguments); //func is available through closure } return result; }; }; document.addEventListener("scroll", throttle(foo, 1000)); //document.addEventListener("scroll", throttle(foo(5), 2000)); }()); But I'd like to modify foo to foo(x) and get this to work (function () { var lastTime = new Date().getTime(); function foo(x) { var newTime = new Date().getTime(); var gap = newTime - lastTime; // Travels up scope chain to use parents lastTime. Function has access to variables declared in the same scope console.log('foo called, gap:' + gap); lastTime = newTime; // Updates lastTime console.log(x); x++; } var throttle = function(func, wait) { var result; var timeout = null; // flag updated through closure var previous = 0; // time last run updated through closure return function() { //func, wait, timeout, previous available through scope var now = new Date().getTime(); var remaining = wait - (now - previous); if (remaining <= 0) { clearTimeout(timeout); timeout = null; previous = now; result = func.apply(this, arguments); //func is available through closure } return result; }; }; document.addEventListener("scroll", throttle(foo(5), 2000)); }());

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• Web Services, Memory Leaks and CRM

  - by Neil

  Hi, I have a website that allows users to upload a csv file. This calls a service that reads the information from the csv, puts it into DynamicEntity objects and calls the CRM service to Create/Update entities in CRM. When this service creates/updates an entity this kicks off other plugins to apply certain business rules. These rules can also Create or Update entites in CRM. The issue here is that the handle count of the w3wp.exe process that the website is calling increases every time the an entity is created or updated and it never comes back down. I tried putting Garbage Collection code in the business rules and this reduces the handle count of the CRM w3wp process (run by the Network Service), but not the other w3wp process. Should I have Dispose methods on the Web Service that calls the CRM service? I hope that makes sense. I'm not overly familiar with memory management issues so any help is appreciated. Can anybody give me some tips on how to stop this from occurring? Thanks, Neil -- EDIT Okay well the handle count goes up when I call the Service.Create(DynamicEntity) method. I don't think placing any code here would be beneficial. When I exit the method/class/service that contains this call the handle count stays as it is. What I need to know is whether this is something I should be managing or is it something CRM takes care of (or doesn't take care of but I can't do anything about it) -- Another Edit Right this is how it works. 1) We have CRM and its related services 2) We have another service independent of CRM that uses the CRM services (number 1 above) to create entities based on csv info passed into it 3) We have a website that allows a user to upload a csv, and calls service no 2 above to Create/Update entities in CRM 4) We have plugins fired by CRM which use Service 1 above to create/update entities So the user uploads a csv to the website (3), this fires a service(2). When service 2 creates an entity using service 1, Service 4 fires. Service 4 calls also uses service 1 to Create entities, and when these services are called (using the Service.Create() method) the handle count of the process increases. When the method/class/services finish the handle count remains the same, and so when the whole process occurs again the handle count will increased again.

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• Code to generate random numbers in C++

  - by user1678927

  Basically I have to write a program to generate random numbers to simulate the rolling of a pair of dice. This program should be constructed in multiple files. The main function should be in one file, the other functions should be in a second source file, and their prototypes should be in a header file. First I write a short function that returns a random value between 1 and 6 to simulate the rolling of a single 6-sided die.Second, i write a function that pretends to roll a pair of dice by calling this function twice. My program starts by asking the user how many rolls should be made. Then I write a function to simulate rolling the dice this many times, keeping a count of exactly how many times the values 2,3,4,5,6,7,8,9,10,11,12(each number is the sum of a pair of dice) occur in an array. Later I write a function to display a small bar chart using these counts that ideally would look something like below for a sample of 144 rolls, where the number of asterisks printed corresponds to the count: 2 3 4 5 6 7 8 9 10 11 12 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Next, to see how well the random number generator is doing, I write a function to compute the average value rolled. Compare this to the ideal average of 7. Also, print out a small table showing the counts of each roll made by the program, the ideal count based on the frequencies above given the total number of rolls, and the difference between these values in separate columns. This is my incomplete code so far: "Compiler visual studio 2010" int rolling(){ //Function that returns a random value between 1 and 6 rand(unsigned(time(NULL))); int dice = 1 + (rand() %6); return dice; } int roll_dice(int num1,int num2){ //it calls 'rolling function' twice int result1,result2; num1 = rolling(); num2 = rolling(); result1 = num1; result2 = num2; return result1,result2; } int main(void){ int times,i,sum,n1,n2; int c1,c2,c3,c4,c5,c6,c7,c8,c9,c10,c11;//counters for each sum printf("Please enter how many times you want to roll the dice.\n") scanf_s("%i",&times); I pretend to use counters to count each sum and store the number(the count) in an array. I know i need a loop (for) and some conditional statements (if) but m main problem is to get the values from roll_dice and store them in n1 and n2 so then i can sum them up and store the sum in 'sum'.

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• PHP resized image functions and S3 upload functions - but how to merge the two?

  - by chocolatecoco

  I am using S3 to store images and I am resizing and compressing images before it gets uploaded using PHP. I'm using this class for storing the images to an S3 bucket - http://undesigned.org.za/2007/10/22/amazon-s3-php-class This all works fine if I'm not doing any file processing before the file is uploaded because it reads the file upload from the $_FILES array. The problem is I am resizing and compressing the image before storing to the S3 bucket. So I'm no longer able to read from the $_FILES array. The functions for resizing: public function resizeImage($newWidth, $newHeight, $option="auto") { // *** Get optimal width and height - based on $option $optionArray = $this->getDimensions($newWidth, $newHeight, $option); $optimalWidth = $optionArray['optimalWidth']; $optimalHeight = $optionArray['optimalHeight']; // *** Resample - create image canvas of x, y size $this->imageResized = imagecreatetruecolor($optimalWidth, $optimalHeight); imagecopyresampled($this->imageResized, $this->image, 0, 0, 0, 0, $optimalWidth, $optimalHeight, $this->width, $this->height); // *** if option is 'crop', then crop too if ($option == 'crop') { $this->crop($optimalWidth, $optimalHeight, $newWidth, $newHeight); } } The script I am using to store the file after resizing and compressing to a local directory: public function saveImage($savePath, $imageQuality="100") { // *** Get extension $extension = strrchr($savePath, '.'); $extension = strtolower($extension); switch($extension) { case '.jpg': case '.jpeg': if (imagetypes() & IMG_JPG) { imagejpeg($this->imageResized, $savePath, $imageQuality); } break; case '.gif': if (imagetypes() & IMG_GIF) { imagegif($this->imageResized, $savePath); } break; case '.png': // *** Scale quality from 0-100 to 0-9 $scaleQuality = round(($imageQuality/100) * 9); // *** Invert quality setting as 0 is best, not 9 $invertScaleQuality = 9 - $scaleQuality; if (imagetypes() & IMG_PNG) { imagepng($this->imageResized, $savePath, $invertScaleQuality); } break; // ... etc default: // *** No extension - No save. break; } imagedestroy($this->imageResized); } with this PHP code to invoke it: $resizeObj = new resize("$images_dir/$filename"); $resizeObj -> resizeImage($thumbnail_width, $thumbnail_height, 'crop'); $resizeObj -> saveImage($images_dir."/tb_".$filename, 90); How do I modify the code above so I can pass it through this function: $s3->putObjectFile($thefile, "s3bucket", $s3directory, S3::ACL_PUBLIC_READ)

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• Better way to write an object generator for an RAII template class?

  - by Dan

  I would like to write an object generator for a templated RAII class -- basically a function template to construct an object using type deduction of parameters so the types don't have to be specified explicitly. The problem I foresee is that the helper function that takes care of type deduction for me is going to return the object by value, which will result in a premature call to the RAII destructor when the copy is made. Perhaps C++0x move semantics could help but that's not an option for me. Anyone seen this problem before and have a good solution? This is what I have: template<typename T, typename U, typename V> class FooAdder { private: typedef OtherThing<T, U, V> Thing; Thing &thing_; int a_; // many other members public: FooAdder(Thing &thing, int a); ~FooAdder(); void foo(T t, U u); void bar(V v); }; The gist is that OtherThing has a horrible interface, and FooAdder is supposed to make it easier to use. The intended use is roughly like this: FooAdder(myThing, 2) .foo(3, 4) .foo(5, 6) .bar(7) .foo(8, 9); The FooAdder constructor initializes some internal data structures. The foo and bar methods populate those data structures. The ~FooAdder dtor wraps things up and calls a method on thing_, taking care of all the nastiness. That would work fine if FooAdder wasn't a template. But since it is, I would need to put the types in, more like this: FooAdder<Abc, Def, Ghi>(myThing, 2) ... That's annoying, because the types can be inferred based on myThing. So I would prefer to create a templated object generator, similar to std::make_pair, that will do the type deduction for me. Something like this: template<typename T, typename U, typename V> FooAdder<T, U, V> AddFoo(Thing &thing, int a) { return FooAdder<T, U, V>(thing, a); } That seems problematic: because it returns by value, the stack temporary object will be destructed, which will cause the RAII dtor to run prematurely. One thought I had was to give FooAdder a copy ctor with move semantics, kinda like std::auto_ptr. But I would like to do this without dynamic memory allocation, so I thought the copy ctor could set a flag within FooAdder indicating the dtor shouldn't do the wrap-up. Like this: FooAdder(FooAdder &rhs) // Note: rhs is not const : thing_(rhs.thing_) , a_(rhs.a_) , // etc... lots of other members, annoying. , moved(false) { rhs.moved = true; } ~FooAdder() { if (!moved) { // do whatever it would have done } } Seems clunky. Anyone got a better way?

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• Issue when rotating a UIScrollView

  - by leachianus.gecko

  I am having issues trying to get the pageControl sample code to work with rotation. I managed to get it to rotate but it does not visually load correctly until I start to scroll (then it works fine). Any Idea on how I can fix this problem? Here is a link to the project if you want to see it in action. This code is based off the PageControl example apple has provided. here is the code: #import "ScrollingViewController.h" #import "MyViewController.h" @interface ScrollingViewController (PrivateMethods) - (void)loadScrollViewWithPage:(int)page; @end @implementation ScrollingViewController @synthesize scrollView; @synthesize viewControllers; - (void)viewDidLoad { amount = 5; [super viewDidLoad]; [self setupPage]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; } - (void)viewDidUnload { [scrollView release]; } - (void)dealloc { [super dealloc]; } - (void)setupPage { NSMutableArray *controllers = [[NSMutableArray alloc] init]; for (unsigned i = 0; i < amount; i++) { [controllers addObject:[NSNull null]]; } self.viewControllers = controllers; [controllers release]; // a page is the width of the scroll view scrollView.pagingEnabled = YES; scrollView.contentSize = CGSizeMake(scrollView.frame.size.width * amount, 200); scrollView.showsHorizontalScrollIndicator = NO; scrollView.showsVerticalScrollIndicator = NO; scrollView.scrollsToTop = NO; scrollView.delegate = self; [self loadScrollViewWithPage:0]; [self loadScrollViewWithPage:1]; } #pragma mark - #pragma mark UIScrollViewDelegate stuff - (void)scrollViewDidScroll:(UIScrollView *)_scrollView { if (pageControlIsChangingPage) { return; } /* * We switch page at 50% across */ CGFloat pageWidth = _scrollView.frame.size.width; int dog = floor((_scrollView.contentOffset.x - pageWidth / 2) / pageWidth) + 1; // pageControl.currentPage = page; [self loadScrollViewWithPage:dog - 1]; [self loadScrollViewWithPage:dog]; [self loadScrollViewWithPage:dog + 1]; } - (void)loadScrollViewWithPage:(int)page { if (page < 0) return; if (page >= amount) return; MyViewController *controller = [viewControllers objectAtIndex:page]; if ((NSNull *)controller == [NSNull null]) { controller = [[MyViewController alloc] initWithPageNumber:page]; [viewControllers replaceObjectAtIndex:page withObject:controller]; [controller release]; } if (nil == controller.view.superview) { CGRect frame = scrollView.frame; frame.origin.x = frame.size.width * page; frame.origin.y = 0; controller.view.frame = frame; [scrollView addSubview:controller.view]; } } - (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation { [self setupPage]; } - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { // Return YES for supported orientations return YES; } @end

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• c++ property class structure

  - by Without me Its just Aweso

  I have a c++ project being developed in QT. The problem I'm running in to is I am wanting to have a single base class that all my property classes inherit from so that I can store them all together. Right now I have: class AbstractProperty { public: AbstractProperty(QString propertyName); virtual QString toString() const = 0; virtual QString getName() = 0; virtual void fromString(QString str) = 0; virtual int toInteger() = 0; virtual bool operator==(const AbstractProperty &rightHand) = 0; virtual bool operator!=(const AbstractProperty &rightHand) = 0; virtual bool operator<(const AbstractProperty &rightHand) = 0; virtual bool operator>(const AbstractProperty &rightHand) = 0; virtual bool operator>=(const AbstractProperty &rightHand) = 0; virtual bool operator<=(const AbstractProperty &rightHand) = 0; protected: QString name; }; then I am implementing classes such as PropertyFloat and PropertyString and providing implementation for the comparator operators based on the assumption that only strings are being compared with strings and so on. However the problem with this is there would be no compiletime error thrown if i did if(propertyfloat a < propertystring b) however my implementation of the operators for each derived class relies on them both being the same derived class. So my problem is I cant figure out how to implement a property structure so that I can have them all inherit from some base type but code like what I have above would throw a compile time error. Any ideas on how this can be done? For those familiar with QT I tried using also a implementation with QVariant however QVariant doesn't have operators < and defined in itself only in some of its derived classes so it didn't work out. What my end goal is, is to be able to generically refer to properties. I have an element class that holds a hashmap of properties with string 'name' as key and the AbstractProperty as value. I want to be able to generically operate on the properties. i.e. if I want to get the max and min values of a property given its string name I have methods that are completely generic that will pull out the associated AbstactProperty from each element and find the max/min no matter what the type is. so properties although initially declared as PropertyFloat/PropertyString they will be held generically.

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• avoiding enums as interface identifiers c++ OOP

  - by AlasdairC

  Hi I'm working on a plugin framework using dynamic loaded shared libraries which is based on Eclipse's (and probally other's) extension-point model. All plugins share similar properties (name, id, version etc) and each plugin could in theory satisfy any extension-point. The actual plugin (ie Dll) handling is managed by another library, all I am doing really is managing collections of interfaces for the application. I started by using an enum PluginType to distinguish the different interfaces, but I have quickly realised that using template functions made the code far cleaner and would leave the grunt work up to the compiler, rather than forcing me to use lots of switch {...} statements. The only issue is where I need to specify like functionality for class members - most obvious example is the default plugin which provides a particular interface. A Settings class handles all settings, including the default plugin for an interface. ie Skin newSkin = settings.GetDefault<ISkin>(); How do I store the default ISkin in a container without resorting to some other means of identifying the interface? As I mentioned above, I currently use a std::map<PluginType, IPlugin> Settings::defaults member to achieve this (where IPlugin is an abstract base class which all plugins derive from. I can then dynamic_cast to the desired interface when required, but this really smells of bad design to me and introduces more harm than good I think. would welcome any tips edit: here's an example of the current use of default plugins typedef boost::shared_ptr<ISkin> Skin; typedef boost::shared_ptr<IPlugin> Plugin; enum PluginType { skin, ..., ... } class Settings { public: void SetDefault(const PluginType type, boost::shared_ptr<IPlugin> plugin) { m_default[type] = plugin; } boost::shared_ptr<IPlugin> GetDefault(const PluginType type) { return m_default[type]; } private: std::map<PluginType, boost::shared_ptr<IPlugin> m_default; }; SkinManager::Initialize() { Plugin thedefault = g_settings.GetDefault(skinplugin); Skin defaultskin = boost::dynamic_pointer_cast<ISkin>(theskin); defaultskin->Initialize(); } I would much rather call the getdefault as the following, with automatic casting to the derived class. However I need to specialize for every class type. template<> Skin Settings::GetDefault<ISkin>() { return boost::dynamic_pointer_cast<ISkin>(m_default(skin)); }

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• jQuery multiple if else Statements

  - by Chris MMgr

  I have a set of images that I am trying to activate (change opacity) based on the position of a user's window. The below code works, but only through a long series of if else statements. Is there a way to shorten the below code? //Function to activate and deactivate the buttons on the side menu function navIndicator() { var winNow = $(window).scrollTop(); var posRoi = $('#roi').offset(); var posRoiNow = posRoi.top; //Activate the propper button corresponding to what section the user is viewing if (winNow == posRoiNow * 0) { $('#homeBut a img.active').stop().animate({ opacity: 1 } { queue: false, duration: 300, easing: "easeOutExpo" }); $('#homeBut').addClass("viewing") } else { $('#homeBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#homeBut').removeClass("viewing") } if (winNow == posRoiNow) { $('#roiBut a img.active').stop().animate({ opacity: 1 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#roiBut').addClass("viewing") } else { $('#roiBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#roiBut').removeClass("viewing") } if (winNow == posRoiNow * 2) { $('#dmsBut a img.active').stop().animate({ opacity: 1 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#dmsBut').addClass("viewing") } else { $('#dmsBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#dmsBut').removeClass("viewing") } if (winNow == posRoiNow * 3) { $('#techBut a img.active').stop().animate({ opacity: 1 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#techBut').addClass("viewing") } else { $('#techBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#techBut').removeClass("viewing") } if (winNow == posRoiNow * 4) { $('#impBut a img.active').stop().animate({ opacity: 1 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#impBut').addClass("viewing") } else { $('#impBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#impBut').removeClass("viewing") } if (winNow == posRoiNow * 5) { $('#virBut a img.active').stop().animate({ opacity: 1 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#virBut').addClass("viewing") } else { $('#virBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#virBut').removeClass("viewing") } if (winNow == posRoiNow * 6) { $('#biBut a img.active').stop().animate({ opacity: 1 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#biBut').addClass("viewing") } else { $('#biBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#biBut').removeClass("viewing") } if (winNow == posRoiNow * 7) { $('#contBut a img.active').stop().animate({ opacity: 1 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#contBut').addClass("viewing") } else { $('#contBut a img.active').stop().animate({ opacity: 0 }, { queue: false, duration: 300, easing: "easeOutExpo" }); $('#contBut').removeClass("viewing") } };

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• Table row height in Internet Explorer

  - by Fritz H

  I have the following table: <table> <tr> <td style="height: 7px; width: 7px"> A1 </td> <td style="height: 7px"> B1 </td> <td style="height: 7px; width: 7px"> C1 </td> </tr> <tr> <td style="width: 7px"> A2 </td> <td> B2 </td> <td style="width: 7px"> C2 </td> </tr> <tr> <td style="height: 7px; width: 7px"> A3 </td> <td style="height: 7px"> B3 </td> <td style="height: 7px; width: 7px"> C3 </td> </tr> </table> The basic idea is that the first row must be 7 pixels high. The left- and rightmost cells (A1 and C1) must be 7px wide, and the middle cell (B1) must scale according to the width of the table. The same goes for the bottom row (A3, B3, C3). The middle row, however, needs to scale in height - in other words, it needs to be (tableheight - 14px). The left- and rightmost cells (A2, C2) need to be 7 pixels wide. An example: 7px x 7px |------|-------------------------|------| --- +------+-------------------------+------+ | | | | | | 7px | | | | | | | | | --- +------+-------------------------+------+ | | | | | | | | | | | | | | | | | | | | | y | | | | | | | | | | | | | | | | | | | | | | | | --- +------+-------------------------+------+ | | | | | | 7px | | | | | | | | | --- +------+-------------------------+------+ HOWEVER: In Internet Explorer, the widths work fine (columns A and C are 7px, column B scales dynamically) - but the heights don't. Rows 1, 2 and 3 turn out to be exactly 33% of the height of the table, no matter what I do. Unfortunately I have to use this table, so replacing it with a set of DIVs is not an option. I have the following DOCTYPE: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> I need to keep this, as some other elements on the page rely on some complex CSS-based layouts. Can anyone point me in the right direction to whip this into shape for IE? EDIT: Should have mentioned earlier - this table is resized on the fly using javascript.

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• Mysql select most frequent and sort alphabetically

  - by user2605793

  I am trying to select the most common 100 names from a table then display the list showing the names and count. I want the user to be able to re-sort the list alphabetically rather than based on count. I thought the following code would do it. It works for the default sort by count but fails on the sort alphabetically. The line "$count = mysql_num_rows($table);" gives an error: mysql_num_rows() expects parameter 1 to be resource, boolean given. Any help would be greatly appreciated. // Get most popular surnames echo '<h2>Most Common Surnames</h2>'; if ($sort == "") { // default sort by count echo '<a href="http://mysite/names.php?id='.$id.'&sort=name">Sort by name</a><br>'; $query = "SELECT family_name, COUNT(*) as count FROM namefile WHERE record_key = $id GROUP BY family_name ORDER BY count DESC LIMIT 100"; } else { // sort alphabetically echo '<a href="http://mysite/names.php?id='.$id.'">Sort by count</a><br>'; $query = "SELECT * FROM ( SELECT family_name, COUNT(*) as count FROM namefile WHERE record_key = $id GROUP BY family_name ORDER BY count DESC LIMIT 100) AS alpha ORDER BY family_name"; } $table = mysql_query($query); $count = mysql_num_rows($table); $tot = 0; $i = 0; echo '<table><tr>'; while ($tot < $count2) { $rec2 = mysql_fetch_array($table2); echo '<td>'.$rec2[0].'</td><td>'.$rec2[1].'</td><td width="40">&nbsp;</td><td>'; if ($i++ == 6) { echo '</tr><tr>'; $i = 0; } $tot++; } echo '</tr></table><br>'; UPDATE: I needed to add "AS alpha" to give the outer select a unique name. (alpha is just a random name I made up.) It now works perfectly. Code updated for the benefit of any others who need something similar.

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• Preg_replace regex, newlines, connection resets

  - by bob_the_destroyer

  I have mixed html, custom code, and regular text I need to examine and change frequently on several, long wiki pages. I'm working with a proprietary wiki-like application and have no control over how the application functions or validates user input. The layout of pages that users add must follow a very specific standard layout and always include very specific text in only certain places - a standard which frequently changes. If users add pages that are so far out of the standard, they will be deleted. The fact that all this is obviously a complete waste of time when alternative platforms to do exactly what's needed here exist is already understood. I've built a PHP based API to automate this post-validation and frequent restandardization process for me. I've been able set up regex patterns to handle all this mixed text, and they all work fine for handling single lines. The problem I have is this: Poorly formed regex against long text with line breaks can lead to unexpected results, such as connection resets. I have no access to server-side logs to troubleshoot. How do I overcome this? This is just one example of what I currently have: {column} and {section} tags I'm searching for below can have any number of attributes, and wrap any text. {section} may or may not exist and may or may not be one or more lines under {column}, but it has to be wrapped inside {column}. {column} itself may or may not exist, and if it doesn't, I don't care. I want to grab the inner section contents and wrap it in an html div tag. I can't recall the exact pattern I'm using offhand at the moment, but it's close enough... $pattern = "/\{column:id=summary([|]?([a-zA-Z0-9-_ ]+[:][a-zA-Z0-9-_ ]+[ ]?))\}(.*)({section([|]([a-zA-Z0-9-_ ]+[:][a-zA-Z0-9-_ ]+[ ]?))\}(.*)\{section\}(.*))?{column\}/s"; $replacement = "{html}<div id='summary'$7</div{html}"; $text = preg_replace($pattern, $replacement, $subject); Handling the {column} and {section} attributes and passing only valid HTML parameters to the new html div or a subtext of it is itself a challenge, but my main focus above right now is getting that (.*) value within {section} above without causing a connection reset. Any pointers?

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• wxWidgets: Show a window that was marked hidden in the XRC

  - by jdwieber

  I'm new to wxWidgets and DialogBlocks. I have a form that is created using DialogBlocks and saved as an XRC file. Part of the form has a vertical wxStaticBoxSizer into which is placed two wxScrolledWindow elements. I want to only show one at a time based on what data is to be shown to the user, so I have one marked hidden and left the other one visible. In code (C++), when I try to switch the display and show the widget that was hidden in the XRC and hide the one that was not, the one that I hide goes away fine, but the one that I want to show is not visible. If I resize the window however, it appears. Once it has appeard then I can switch back and forth with no issues. I tried many combinations of showing, enabling, invalidating, getting the sizer and calling RecalcSizes, refresh, layout, and some others. I tried them in different combinations too. Simply calling Show will allow me to toggle between the two, but only after I switch to the one that does not show initially and resize the window. From what I see in the docs. the issue is that wxSizer doesn't allocate space for hidden windows, but there is a flag that can be set to override that behavor. My problem is that DialogBlocks does not expose that feature, so if I manually edit the XRC file the modifation will be lost when I, or one of the other devs. saves some changes. Is ther a sequence of calls that I can make to tell the sizer to allocate space? The default OnResize handler does something to cause the sizer to allocate space, but I don't know what that is, or how to do it. This is the flag I found in the docs: wxRESERVE_SPACE_EVEN_IF_HIDDEN Normally wxSizers don't allocate space for hidden windows or other items. This flag overrides this behavior so that sufficient space is allocated for the window even if it isn't visible. This makes it possible to dynamically show and hide controls without resizing parent dialog, for example. This function is new since wxWidgets version 2.8.8 Thanks in advance.

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• Sharing the same file between different projects

  - by selsine

  Hi Everyone, For version control we currently use Visual Source Safe and are thinking of migrating to another version control system (SVN, Mercurial, Git). Currently we use Visual Source Safe's "Shared" file feature quite heavily. This allows us to share code between design and runtimes of a single product, and between multiple products as well. For example: **Product One** - Design Login.cpp Login.h Helper.cpp Helper.h - Runtime Login.cpp Login.h Helper.cpp Helper.h **Product Two** - Design Login.cpp Login.h - Launcher Login.cpp Login.h - Runtime Login.cpp Login.h In this example Login.cpp and Login.h contain common code that all of our projects need, Helper.cpp and Helper.h is only used in Product One. In Visual Source Safe they are shared between the specific projects, which means that whenever the files are updated in one project they are updated in any project they are shared with. This is a simple example but hopefully it explains why we use the shared feature: to reduce the amount of duplicated code and ensure that when a bug is fixed all projects automatically have access to the new fixed code. After researching alternatives to Visual Source Safe it seems that most version control systems do not have the idea of shared files, instead they seem to use the idea of sub repositories. (http://mercurial.selenic.com/wiki/subrepos http://svnbook.red-bean.com/en/1.0/ch07s03.html) My question (after all of that) is about what the best practices for achieving this are using other version control systems? Should we restructure our projects so that two copies of the files do not exist and an include directory is used instead? e.g. Product One Design Login.cpp Login.h Runtime Login.cpp Login.h Common Helper.cpp Helper.h This still leaves what to do with Login.cpp and Logon.h Should the shared files be moved to their own repository and then compiled into a lib or dll? This would make bug fixing more time consuming as the lib projects would have to be edited and then rebuilt. Should we use externals or sub repositories? Should we combine our projects (i.e. runtime, design, and launcher) into one large project? Any help would be appreciated. We have the feeling that our project design has evolved based on the tools that we used and now that we are thinking of switching tools it's difficult for us to see how we can best modify our practices. Or maybe we are the only people are there doing this...? Also, we use Visual Studio for all of our stuff. Thanks.

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• Populating data in multiple cascading dropdown boxes in Access 2007

  - by miCRoSCoPiC_eaRthLinG

  Hello all, I've been assigned the task to design a temporary customer tracking system in MS Access 2007 (sheeeesh!). The tables and relationships have all been setup successfully. But I'm running into a minor problem while trying to design the data entry form for one table... Here's a bit of explanation first. The screen contains 3 dropdown boxes (apart from other fields). 1st dropdown The first dropdown (cboMarket) represents the Market lets users select between 2 options: Domestic International Since the first dropdown contains only 2 items I didn't bother making a table for it. I added them as pre-defined list items. 2nd dropdown Once the user makes a selection in this one, the second dropdown (cboLeadCategory) loads up a list of Lead Categories, namely, Fairs & Exhibitions, Agents, Press Ads, Online Ads etc. Different sets of lead categories are utilized for the 2 markets. Hence this box is dependent on the 1st one. Structure of the bound table, named Lead_Cateogries for the 2nd combo is: ID Autonumber Lead_Type TEXT <- actually a list that takes up Domestic or International Lead_Category_Name TEXT 3rd dropdown And based on the choice of category in the 2nd one, the third one (cboLeadSource) is supposed to display a pre-defined set of lead sources belonging to the particular category. Table is named Lead_Sources and the structure is: ID Autonumber Lead_Category NUMBER <- related to ID of Lead Categories table Lead_Source TEXT When I make the selection in the 1st dropdown, the AfterUpdate event of the combo is called, which instructs the 2nd dropdown to load contents: Private Sub cboMarket_AfterUpdate() Me![cboLead_Category].Requery End Sub The Row Source of the 2nd combo contains a query: SELECT Lead_Categories.ID, Lead_Categories.Lead_Category_Name FROM Lead_Categories WHERE Lead_Categories.Lead_Type=[cboMarket] ORDER BY Lead_Categories.Lead_Category_Name; The AfterUpdate event of 2nd combo is: Private Sub cboLeadCategory_AfterUpdate() Me![cboLeadSource].Requery End Sub The Row Source of 3rd combo contains: SELECT Leads_Sources.ID, Leads_Sources.Lead_Source FROM Leads_Sources WHERE [Lead_Sources].[Lead_Category]=[Lead_Categories].[ID] ORDER BY Leads_Sources.Lead_Source; Problem When I select Market type from cboMarket, the 2nd combo cboLeadCategory loads up the appropriate Categories without a hitch. But when I select a particular Category from it, instead of the 3rd combo loading the lead source names, a modal dialog is displayed asking me to Enter a Parameter. When I enter anything into this prompt (valid or invalid data), I get yet another prompt: Why is this happening? Why isn't the 3rd box loading the source names as desired. Can any one please shed some light on where I am going wrong? Thanks, m^e

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• Can't get jQuery to get focus on cloned input fields

  - by Rebel1Moon

  I have a page that needs to create dynamic form fields as often as the user needs, and I am trying to use Ajax to tie it in to my database for faster form entry and to prevent user typos. So, I have put my Ajax returned data into popup div, the user selects, then the form field is filled in. The problem comes on the cloned fields. They don't seem to want to bring up the popup div when focused. I am thinking it is something to do with when they get created/added to the DOM. Here is my JS that creates the clones: $(document).ready(function() { var regex = /^(.*)(\d)+$/i; var cloneIndex = $(".clonedInput").length; $("button.clone").live("click", function(){ $(this).parents(".clonedInput").clone() .appendTo("#course_container") .attr("id", "clonedInput" + cloneIndex) .find("*").each(function() { var id = this.id || ""; var match = id.match(regex) || []; if (match.length == 3) { this.id = match[1] + (cloneIndex); } }); cloneIndex++; numClones=cloneIndex-1; //alert("numClones "+numClones); }); Here is where I expect to be able to get focus on the correct cloned field and call the popup. The baker_equiv0 id is original code, whereas baker_equiv1 is the first clone. $('#baker_equiv0').focus(function() { \\ THIS CODE WORKS $('.popup').fadeIn(500); $('#results').empty(); // document.enter_data.baker_equiv1.value="test"; THIS LINE WORKS //alert("numClones "+numClones); }); $('#baker_equiv1').focus(function() { // THIS DOESN'T EVER FIRE alert("numClones "+numClones); $('.popup').fadeIn(500); $('#results').empty(); }); Here is the HTML with the form: <label for="baker_equiv" class="">Baker Equivalent: <span class="requiredField">*</span></label> <input type="text" class="cinputsa" name="baker_equiv[]" id="baker_equiv0" size="8" ONKEYUP="get_equiv(this.value);"> If I put this in the HTML code above, it works fine: onfocus="alert(this.id)" I'd also be interested in how to adjust the JS code to work based on the id array created rather than having to copy code for each potential set of fields clones, i.e., baker_equiv[] rather than baker_equiv0, baker_equiv1, etc. Thanks all!

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• Help with PHP and associative arrays

  - by errata

  Hello. I have to do a simple calculator in php based on user's input and choice from select field, something like this: <?php $a = $_GET['a']; $b = $_GET['b']; $array = array( "option1" => 0.1, "option2" => 0.15, "option3" => 0.3, "option4" => 3, "option5" => 3, "option6" => 16, "option7" => 16, "option8" => 16 ); echo "<form action='calc.php' method='get'>"; echo "<input type='text' name='a' value='".$a."'> of "; echo "<select name='b'>"; foreach ($array as $k => $v) { echo "<option value='".$v."'>".$k."</option>"; } echo "</select> "; echo "<input type='submit' value='='> "; $total_volume = $a * $b; echo $total_volume; echo "</form>"; ?> Well, for now everything works fine, but the idea is that after user submits form, the page reloads with sent amount in input field and selected option which user actually selected... First thing is easy: I just put value="a" in my input field, but I'm not sure how to make a selected option in <select> field??? I started with this: foreach ($array as $k => $v) { echo "<option value='".$v."'"; if ($b == $v) { echo " selected "; } echo ">".$k."</option>"; } ...but this is obviously not working as expected... Please help me with this easy one :) Thanks!

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• Getting caught in loops - R

  - by user334898

  I am looking at whether or not certain 'systems' for betting really do work as claimed, namely, that they have a positive expectation. One such system is based on the rebate on loss. You basically have a large master pot, say $1 million. Your bankroll for each game is $50k. The way it works, is as follows: 1) Start with $50k, always bet on banker 2) If you win, add the money to the master pot. Then play again with $50k. 3) If you lose(now you're at $30k) play till you either: (a) hit 0, you get a rebate of 10%. Begin playing again with $50k+5k=$55k. (b) If you win more than the initial bankroll, add the money to the master pot. Then play again with $50k. 4) Continue until you double the master pot. I just cant find an easy way of programming out the possible cases in R, since you can eventually go down an improbable path. For example, you start at 50k, lose 20, win 19, now you're at 49, now you lose 20, lose 20, now youre at 9, you either lose 9 and get back 5k or you win and this cycle continues until you either end up with more than 50k or hit 0 and get the rebate on the 50k and start again with $50k +5k. Here's some code i started, but i havent figured out a good way of handling the cases where you get stuck and keeping track of the number of games played. Thanks again for your help. Obviously, I understand you may be busy and not have time. p.loss <- .4462466 p.win <- .4585974 p.tie <- 1 - (p.win+p.loss) prob <- c(p.win,p.tie,p.loss) bet<-20 x <- c(19,0,-20) r <- 10 # rebate = 20% br.i <- 50 br<-200 #for(i in 1:100){ # cbr.i<-0 y <- sample(x,1,replace=T,prob) cbr.i<-y+br.i if(cbr.i > br.i){ br<-br+(cbr.i-br.i); cbr.i<-br.i; }else{ y <- sample(x,2,replace=T,prob); if( sum(y)< cbr.i ){ cbr.i<-br.i+(1/r)*br.i; br<-br-br.i} cbr.i<-y+ }else{ cbr.i<- sum(y) + cbr.i; }if(cbr.i <= bet){ y <- sample(x,1,replace=T,prob) if(abs(y)>cbr.i){ cbr.i<-br.i+(1/r)*br.i } }

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• JavaScript: Can I declare a variable by querying which function is called? (Newbie)

  - by belle3WA

  I'm working with an existing JavaScript-powered cart module that I am trying to modify. I do not know JS and for various reasons need to work with what is already in place. The text that appears for my quantity box is defined within an existing function: function writeitems() { var i; for (i=0; i<items.length; i++) { var item=items[i]; var placeholder=document.getElementById("itembuttons" + i); var s="<p>"; // options, if any if (item.options) { s=s+"<select id='options"+i+"'>"; var j; for (j=0; j<item.options.length; j++) { s=s+"<option value='"+item.options[j].name+"'>"+item.options[j].name+"</option>"; } s=s+"</select>&nbsp;&nbsp;&nbsp;"; } // add to cart s=s+method+"Quantity: <input id='quantity"+i+"' value='1' size='3'/> "; s=s+"<input type='submit' value='Add to Cart' onclick='addtocart("+i+"); return false;'/></p>"; } placeholder.innerHTML=s; } refreshcart(false); } I have two different types of quantity input boxes; one (donations) needs to be prefaced with a dollar sign, and one (items) should be blank. I've taken the existing additem function, copied it, and renamed it so that there are two identical functions, one for items and one for donations. The additem function is below: function additem(name,cost,quantityincrement) { if (!quantityincrement) quantityincrement=1; var index=items.length; items[index]=new Object; items[index].name=name; items[index].cost=cost; items[index].quantityincrement=quantityincrement; document.write("<span id='itembuttons" + index + "'></span>"); return index; } Is there a way to declare a global variable based on which function (additem or adddonation) is called so that I can add that into the writeitems function so display or hide the dollar sign as needed? Or is there a better solution? I can't use HTML in the body of the cart page because of the way it is currently coded, so I'm depending on the JS to take care of it. Any help for a newbie is welcome. Thanks!

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• Guilty of unsound programming

  - by TelJanini

  I was reading Robert Rossney's entry on "What's the most unsound program you've had to maintain?" found at: (What's the most unsound program you've had to maintain?) when I realized that I had inadvertently developed a near-identical application! The app consists of an HTTPListener object that grabs incoming POST requests. Based on the information in the header, I pass the body of the request to SQL Server to perform the appropriate transaction. The requests look like: <InvoiceCreate Control="389> <Invoice> <CustomerNumber>5555</CustomerNumber> <Total>300.00</Total> <RushOrder>1</RushOrder> </Invoice> </InvoiceCreate> Once it's received by the HTTPListener object, I perform the required INSERT to the Invoice table using SQL Server's built-in XML handling functionality via a stored procedure: INSERT INTO Invoice (InvoiceNumber, CustomerNumber, Total, RushOrder) SELECT @NEW_INVOICE_NUMBER, @XML.value('(InvoiceCreate/Invoice/CustomerNumber)[1]', 'varchar(10)'), @XML.value('(InvoiceCreate/Invoice/Total)[1]', 'varchar(10)'), @XML.value('(InvoiceCreate/Invoice/Total)[1]', 'varchar(10)') I then use another SELECT statement in the same stored procedure to return the value of the new Invoice Number that was inserted into the Invoices table: SELECT @NEW_INVOICE_NUMBER FOR XML PATH 'InvoiceCreateAck' I then read the generated XML using a SQL data reader object in C# and use it as the response of the HTTPListener object. My issue is, I'm noticing that Robert is indeed correct. All of my application logic exists inside the stored procedure, so I find myself having to do a lot of error-checking (i.e. validating the customer number and invoicenumber values) inside the stored procedure. I'm still a midlevel developer, and as such, am looking to improve. Given the original post, and my current architecture, what could I have done differently to improve the application? Are there any patterns or best practices that I could refer to? What approach would you have taken? I'm open to any and all criticism, as I'd like to do my part to reduce the amount of "unsound programming" in the world.

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• With custom binding for Masonry how would I resize the container appropriately

  - by BigDubb

  Based on the suggestion give here, and the information given here on how to make a custom bindingHandler for a forEach, I decided to attempt to write my own custom binding for a forEach and Masonry. Because the elements are added on the fly the redrawing and moving around of elements to fill the space doesn't occur. So, this functionality needed to be moved after the elements have been rendered or called after each item has been added. Here is my bindingHandler ko.bindingHandlers.masonry = { init: function (element, valueAccessor, allBindingsAccessor) { var $element = $(element), originalContent = $element.html(); $element.data("original-content", originalContent); //var msnry = new Masonry($element); return { controlsDescendantBindings: true } }, update: function (element, valueAccessor, allBindingsAccessor) { var value = ko.utils.unwrapObservable(valueAccessor()), //get the list of items items = value.items(), //get a jQuery reference to the element $element = $(element), //get the current content of the element elementContent = $element.data("original-content"); $element.html(""); var container = $element[0]; var msnry = new Masonry(container); for (var index = 0; index < items.length; index++) { (function () { //get the list of items var item = ko.utils.unwrapObservable(items[index]), $childElement = $(elementContent); ko.applyBindings(item, $childElement[0]); //add the child to the parent $element.append($childElement); msnry.appended($childElement[0]); })(); msnry.layout(); msnry.bindResize(); } } }; and the HTML implementing the handler. <div id="criteriaContainer" data-bind="masonry: { items: SearchItems.Items }"> <div class="searchCriterion control-group"> <label class="control-label" data-bind="text: Description"></label> <div class="controls"> <input type="hidden" data-bind="value: Value, select2: { minimumInputLength: 3, queryUri: SearchUri(), placeholder: Placeholder(), allowClear: true }" style="width: 450px"> </div> <p data-bind="text: Value"></p> </div> </div> When this shows up on the page It stacks all if the elements rendered via the append method right on top of each other. You can see in my bindingHandler I am calling bindResize as well as layout(), neither of which seem to be having any effect. Here's a screenshot of what it looks like in the UI.

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• Meshing different systems of keys together in XML Schema

  - by Tom W

  Hello SO, I'd like to ask people's thoughts on an XSD problem I've been pondering. The system I am trying to model is thus: I have a general type that represents some item in a hypothetical model. The type is abstract and will be inherited by all manner of different model objects, so the model is heterogeneous. Furthermore, some types exist only as children of other types. Objects are to be given an identifier, but the scope of uniqueness of this identifier varies. Some objects - we will call them P (for Parent) objects - must have a globally unique identifier. This is straightforward and can use the xs:key schema element. Other objects (we can call them C objects, for Child) are children of a P object and must have an identifier that is unique only in the scope of that parent. For example, object P1 has two children, object C1 and C2, and object P2 has one child, object C3. In this system, the identifiers given could be as follows: P1: 1 (1st P object globally) P2: 2 (2nd P object globally) C1: 1 (1st C object of P1) C2: 2 (2nd C object of P1) C3: 1 (1st C object of P2) I want the identity syntax of every model object to be identical if possible, therefore my first pass at implementing is to define a single type: <xs:complexType name="ModelElement"> <xs:attribute name="IDMode" type="IdentityMode"/> <xs:attribute name="Identifier" type="xs:string"/> </xs:complexType> where the IdentityMode is an enumerated value: <xs:simpleType name="IdentityMode"> <xs:restriction base="xs:string"> <xs:enumeration value="Identified"/> <xs:enumeration value="Indexed"/> <xs:enumeration value="None"/> </xs:restriction> </xs:simpleType> Here "Identified" signifies a global identifier, and "Indexed" indicates an identifier local only to the parent. My question is, how do I enforce these uniqueness conditions using unique, key or other schema elements based on the IdentityMode property of the given subtype of ModelElement?

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• Efficiently fetching and storing tweets from a few hundred twitter profiles?

  - by MSpreij

  The site I'm working on needs to fetch the tweets from 150-300 people, store them locally, and then list them on the front page. The profiles sit in groups. The pages will be showing the last 20 tweets (or 21-40, etc) by date, group of profiles, single profile, search, or "subject" (which is sort of a different group.. I think..) a live, context-aware tag cloud (based on the last 300 tweets of the current search, group of profiles, or single profile shown) various statistics (group stuffs, most active, etc) which depend on the type of page shown. We're expecting a fair bit of traffic. The last, similar site peaked at nearly 40K visits per day, and ran intro trouble before I started caching pages as static files, and disabling some features (some, accidently..). This was caused mostly by the fact that a page load would also fetch the last x tweets from the 3-6 profiles which had not been updated the longest.. With this new site I can fortunately use cron to fetch tweets, so that helps. I'll also be denormalizing the db a little so it needs less joins, optimize it for faster selects instead of size. Now, main question: how do I figure out which profiles to check for new tweets in an efficient manner? Some people will be tweeting more often than others, some will tweet in bursts (this happens a lot). I want to keep the front page of the site as "current" as possible. If it comes to, say, 300 profiles, and I check 5 every minute, some tweets will only appear an hour after the fact. I can check more often (up to 20K) but want to optimize this as much as possible, both to not hit the rate limit and to not run out of resources on the local server (it hit mysql's connection limit with that other site). Question 2: since cron only "runs" once a minute, I figure I have to check multiple profiles each minute - as stated, at least 5, possibly more. To try and spread it out over that minute I could have it sleep a few seconds between batches or even single profiles. But then if it takes longer than 60 seconds altogether, the script will run into itself. Is this a problem? If so, how can I avoid that? Question 3: any other tips? Readmes? URLs?

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• SQL Design Question regarding schema and if Name value pair is the best solution

  - by Aur

  I am having a small problem trying to decide on database schema for a current project. I am by no means a DBA. The application parses through a file based on user input and enters that data in the database. The number of fields that can be parsed is between 1 and 42 at the current moment. The current design of the database is entirely flat with there being 42 columns; some have repeated columns such as address1, address2, address3, etc... This says that I should normalize the data. However, data integrity is not needed at this moment and the way the data is shaped I'm looking at several joins. Not a bad thing but the data is still in a 1 to 1 relationship and I still see a lot of empty fields per row. So my concerns are that this does not allow the database or the application to be very extendable. If they want to add more fields to be parsed (which they do) than I'd need to create another table and add another foreign key to the linking table. The third option is I have a table where the fields are defined and a table for each record. So what I was thinking is to make a table that stores the value and then links to those two tables. The problem is I can picture the size of that table growing large depending on the input size. If someone gives me a file with 300,000 records than 300,000 x 40 = 12 million so I have some reservations. However I think if I get to that point than I should be happy it is being used. This option also allows for more custom displaying of information albeit a bit more work but little rework even if you add more fields. So the problem boils down to: 1. Current design is a flat file which makes extending it hard and it is not normalized. 2. Normalize the tables although no real benefits for the moment but requirements change. 3. Normalize it down into the name value pair and hope size doesn't hurt. There are a large number of inserts, updates, and selects against that table. So performance is a worry but I believe the saying is design now, performance testing later? I'm probably just missing something practical so any comments would be appreciated even if it’s a quick sanity check. Thank you for your time.

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