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  • Postgres update rule returning number of rows affected

    - by Lithium
    I have a view table which is a union of two seperate tables (say Table _A and Table _B). I need to be able to update a row in the view table, and it seems the way to do this was through a 'view rule'. All entries in the view table have seperate id's, so an id that exists in table _A won't exist in table _B. I created the following rule: CREATE OR REPLACE RULE view_update AS ON UPDATE TO viewtable DO INSTEAD ( UPDATE _A SET foo = false WHERE old.id = _A.id; UPDATE _B SET foo = false WHERE old.id = _B.id; ); If I do an update on table _B it returns the correct number of rows affected (1). However if I update table _A it returns (0) rows affected even though the data was changed. If I swap out the order of the updates then the same thing happens, but in reverse. How can I solve this problem so that it returns the correct number of rows affected. Thanks.

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  • Wrong chapter number on page headers except first page

    - by okhalid
    Hi, I am writing up my thesis in Latex and have a template. It works nicely for every thing else except one. Chapter numbers are correctly incremented on the first page of each chapter but for consecutive pages of each chapter, the header saying "Chapter x - This is a chapter title" have 1 always as chapter number. Following is the code sample from the CLS file which i think is relevant to the headers: \newcommand\btypeout[1]{\bhrule\typeout{\space #1}\bhrule} \def\today{\ifcase\month\or January\or February\or March\or April\or May\or June\or July\or August\or September\or October\or November\or December\fi \space \number\year} \usepackage{setspace} \onehalfspacing \setlength{\parindent}{0pt} \setlength{\parskip}{2.0ex plus0.5ex minus0.2ex} \usepackage{vmargin} \setmarginsrb { 1.5in} % left margin { 0.6in} % top margin { 1.0in} % right margin { 0.8in} % bottom margin { 20pt} % head height {0.25in} % head sep { 9pt} % foot height { 0.3in} % foot sep \raggedbottom \setlength{\topskip}{1\topskip \@plus 5\p@} \doublehyphendemerits=10000 % No consecutive line hyphens. \brokenpenalty=10000 % No broken words across columns/pages. \widowpenalty=9999 % Almost no widows at bottom of page. \clubpenalty=9999 % Almost no orphans at top of page. \interfootnotelinepenalty=9999 % Almost never break footnotes. \usepackage{fancyhdr} \lhead[\rm\thepage]{\fancyplain{}{\sl{\rightmark}}} \rhead[\fancyplain{}{\sl{\leftmark}}]{\rm\thepage} \chead{}\lfoot{}\rfoot{}\cfoot{} \pagestyle{fancy} %% Chapter Heading --------------- \renewcommand{\chaptermark}[1]{\btypeout{\thechapter\space #1}\markboth{\@chapapp\ \thechapter\ #1}{\@chapapp\ \thechapter\ #1}} %%-------------------------------------------------- \renewcommand{\sectionmark}[1]{} \renewcommand{\subsectionmark}[1]{} \def\cleardoublepage{\clearpage\if@twoside \ifodd\c@page\else \hbox{} \thispagestyle{empty} \newpage \if@twocolumn\hbox{}\newpage\fi\fi\fi} Thanks, Omer

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  • AJAX - querying a search engine and returning the number of results

    - by Moddy
    Right, so basically I need to query a selection of search engines in an AJAX app. As there is a number of different search engines - there's no search engine specific API I can use either. My main problem is getting the number of results returned by the search. So far, I have decided it is probably best to use a regexp from the returned search query HTML, and then convert the string of characters to an integer. However, this method just doesn't feel.. clean to me. It seems a bit rough around the edges and I think it could do with improving! I guess not being 100% confident with regular expressions doesn't help; but it just feels like it could be improved. Any ideas on how to implement this would be great cheers! It doesn't seem like that an exotic thing to do, so I was wondering if perhaps any of you guys have done this before and would have a few tips? Note: This is an AJAX app at the moment, but I may be re-writing this functionality in a different app soon - which won't be AJAX. I'm confident I can transfer any AJAX implementation to the other language though.

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  • Windows Batch file to echo a specific line number

    - by Lee
    So for the second part of my current dilemma, I have a list of folders in c:\file_list.txt. I need to be able to extract them (well, echo them with some mods) based on the line number because this batch script is being called by an iterative macro process. I'm passing the line number as a parameter. @echo off setlocal enabledelayedexpansion set /a counter=0 set /a %%a = "" for /f "usebackq delims=" %%a in (c:\file_list.txt) do ( if "!counter!"=="%1" goto :printme & set /a counter+=1 ) :printme echo %%a which gives me an output of %a. Doh! So, I've tried echoing !a! (result: ECHO is off.); I've tried echoing %a (result: a) I figured the easy thing to do would be to modify the head.bat code found here: http://stackoverflow.com/questions/130116/dos-batch-commands-to-read-first-line-from-text-file except rather than echoing every line - I'd just echo the last line found. Not as simple as one might think. I've noticed that my counter is staying at zero for some reason; I'm wondering if the set /a counter+=1 is doing what I think it's doing.

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  • Number of ways to place kings on chess board

    - by Rakesh
    You have an N x N chessboard and you wish to place N kings on it. Each row and column should contain exactly one king, and no two kings should attack each other (two kings attack each other if they are present in squares which share a corner). The kings in the first K rows of the board have already been placed. You are given the positions of these kings as an array pos[ ]. pos[i] is the column in which the king in the ith row has already been placed. All indices are 0-indexed. In how many ways can the remaining kings be placed? Input: The first line contains the number of test cases T. T test cases follow. Each test case contains N and K on the first line, followed by a line having K integers, denoting the array pos[ ] as described above. Output: Output the number of ways to place kings in the remaining rows satisfying the above conditions. Output all numbers modulo 1000000007. Constraints: 1 <= T <= 20 1 <= N <= 16 0 <= K <= N 0 <= pos_i < N The kings specified in the input will be in different columns and not attack each other. Sample Input: 5 4 1 2 3 0 5 2 1 3 4 4 1 3 0 2 6 1 2 Sample Output: 1 0 2 1 18 Explanation: For the first example, there is a king already placed at row 0 and column 2. The king in the second row must belong to column 0. The king in the third row must belong to column 3, and the last king must beong to column 1. Thus there is only 1 valid placement. For the second example, there is no valid placement. How should i approach this problem

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  • Java: Match tokens between two strings and return the number of matched tokens

    - by Cryssie
    Need some help to find the number of matched tokens between two strings. I have a list of string stored in ArrayList (example given below): Line 0 : WRB VBD NN VB IN CC RB VBP NNP Line 1 : WDT NNS VBD DT NN NNP NNP Line 2 : WRB MD PRP VB DT NN IN NNS POS JJ NNS Line 3 : WDT NN VBZ DT NN IN DT JJ NN IN DT NNP Line 4 : WP VBZ DT JJ NN IN NN Here, you can see each string consists of a bunch of tokens separated by spaces. So, there's three things I need to work with.. Compare the first token (WRB) in Line 0 to the tokens in Line 1 to see if they match. Move on to the next tokens in Line 0 until a match is found. If there's a match, mark the matched tokens in Line 1 so that it will not be matched again. Return the number of matched tokens between Line 0 and Line 1. Return the distance of the matched tokens. Example: token NN is found on position 3 on line 0 and position 5 on Line 1. Distance = |3-5| = 2 I've tried using split string and store it to String[] but String[] is fixed and doesn't allow shrinking or adding of new elements. Tried Pattern Matcher but with disasterous results. Tried a few other methods but there's some problems with my nested for loops..(will post part of my coding if it will help). Any advice or pointers on how to solve this problem this would be very much appreciated. Thank you very much.

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  • [UNIX] Sort lines of massive file by number of words on line (ideally in parallel)

    - by conradlee
    I am working on a community detection algorithm for analyzing social network data from Facebook. The first task, detecting all cliques in the graph, can be done efficiently in parallel, and leaves me with an output like this: 17118 17136 17392 17064 17093 17376 17118 17136 17356 17318 12345 17118 17136 17356 17283 17007 17059 17116 Each of these lines represents a unique clique (a collection of node ids), and I want to sort these lines in descending order by the number of ids per line. In the case of the example above, here's what the output should look like: 17118 17136 17356 17318 12345 17118 17136 17356 17283 17118 17136 17392 17064 17093 17376 17007 17059 17116 (Ties---i.e., lines with the same number of ids---can be sorted arbitrarily.) What is the most efficient way of sorting these lines. Keep the following points in mind: The file I want to sort could be larger than the physical memory of the machine Most of the machines that I'm running this on have several processors, so a parallel solution would be ideal An ideal solution would just be a shell script (probably using sort), but I'm open to simple solutions in python or perl (or any language, as long as it makes the task simple) This task is in some sense very easy---I'm not just looking for any old solution, but rather for a simple and above all efficient solution

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  • DOS Batch file to echo a specific line number

    - by Lee
    So for the second part of my current dilemma, I have a list of folders in "c:\file_list.txt". I need to be able to extract them (well, echo them with some mods) based on the line number because this batch script is being called by an iterative macro process. I'm passing the line number as a parameter. @echo off setlocal enabledelayedexpansion set /a counter=0 set /a %%a = "" for /f "usebackq delims=" %%a in (c:\file_list.txt) do (if "!counter!"=="%1" goto :printme & set /a counter+=1) :printme echo %%a which gives me an output of "%a". Doh! So, I've tried echoing !a! (result: "ECHO is off."); I've tried echoing %a (result: a) I figured the easy thing to do would be to modify the "head.bat" code found here: http://stackoverflow.com/questions/130116/dos-batch-commands-to-read-first-line-from-text-file except rather than echoing every line - I'd just echo the last line found. Not as simple as one might think. I've noticed that my counter is staying at zero for some reason; I'm wondering if the "set /a counter+=1" is doing what I think it's doing.

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  • how to ignore ivy revision number?

    - by user315228
    Guys, I have certain jar files without revision number. But as rev is mandatory attribute for ivy dependency, i am providing the revision attribute. But i have something like (-[revision]) in url resolver. but its taking the module number instead of ignoring the revision attribute. I know it wont ignore the revision attribute as its not null. Following is the output that i get default-cache: no cached resolved revision for perltools#perltools;latest.integration [ivy:retrieve] tried [ivy:retrieve] listing all in [ivy:retrieve] using privateRepo to list all in [ivy:retrieve] ApacheURLLister found URL=[httP://myrepo/ivyRepository/perltools/jars/perltools.jar]. [ivy:retrieve] found 1 resources [ivy:retrieve] found revs: [perltools.jar] [ivy:retrieve] HTTP response status: 404 url=httP://myrepo/ivyRepository/perltools/jars/perltools.jar/perltools-perltools.jar.jar [ivy:retrieve] CLIENT ERROR: Not Found url=httP://myrepo/ivyRepository/perltools/jars/perltools.jar/perltools-perltools.jar.jar Can somebody please explain why its taking module.ext as revision where revision i specified is latest.integration and in myrepo, i dont have revision attribute. its just has [http://myrepo/ivyRepository/perltools/jars//perltools.jar] Can somebody please help me so that i can avoid revision attribute?

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  • Calculating a date when a date has been chosen by the number of days

    - by Andy
    I have three selection drop downs in a form comprising of day, month, year. Pretty standard. Ive omitted all the individual select options for the purposes of this question. <label for="start_date">Start Date<font class="required">*</font>:</label> <select name="place_booking[day_val]"> <select name="place_booking[month_val]"> <select name="place_booking[year_val]"> Underneath this i have a selection for the number of days the client wishes to stay at the letting. <label for="number_of_days">Number of Days<font class="required">*</font>:</label> <select name="place_booking[number_of_days]"> Underneath there is a space to display the departure date based on there two selections above. <label for="departure_date">Departure Date<font class="required">*</font>:</label> ? - this bit i would like to display the calculated date after the above is selected Any help would be grealty appreciated.

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  • [PERL Tk] printing Line number in Text widget

    - by ungalnanban
    I use the following code for printing the line number in Text widget. my $c=0; my $r=0; $txt = $mw-Text( -background ='white', -width=>400, -height=>300, -selectbackground => 'skyblue', -insertwidth => 5, -borderwidth =>3, -highlightcolor => 'blue', ### after visit -highlightbackground => 'red' , ### default before visit -xscrollcommand => sub { print"CHAT NO :",$c++; }, # Determines the callback used when the Text widget is scrolled horizontally. -yscrollcommand = sub { print"LINR NO:",$r++; }, # Determines the callback used when the Text widget is scrolled vertically. -padx = 5, -pady = 5, )- pack (); the above code is printing the line number and character no is ok. but I used in Scrolled widget that output is not printing. what is the problem in the following code how can I solve this? $txt = $mw-Scrolled('Text', -scrollbars = 'se', -background ='white', -width=>400, -height=>300, -insertwidth => 5, -borderwidth =>3, -highlightcolor => 'blue', ### after visit -highlightbackground => 'red' , ### default before visit -padx => 5, -pady => 5, -xscrollcommand => sub { print"CHAT NO :",$c++; }, # Determines the callback used when the Text widget is scrolled horizontally. -yscrollcommand => sub { print"LINR NO :",$r++; }, # Determines the callback used when the Text widget is scrolled vertically. )->pack();

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  • Perl - how to get the number of elements in a list (not a named array)

    - by NXT
    Hi Everyone, I'm trying to get a block of code down to one line. I need a way to get the number of items in a list. My code currently looks like this: # Include the lib directory several levels up from this directory my @ary = split('/', $Bin); my @ary = @ary[0 .. $#ary-4]; my $res = join '/',@ary; lib->import($res.'/lib'); That's great but I'd like to make that one line, something like this: lib->import( join('/', ((split('/', $Bin)) [0 .. $#ary-4])) ); But of course the syntax $#ary is meaningless in the above line. Is there equivalent way to get the number of elements in an anonymous list? Thanks! PS: The reason for consolidating this is that it will be in the header of a bunch of perl scripts that are ancillary to the main application, and I want this little incantation to be more cut & paste proof.

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  • adding an uncertain number of fields using javascript

    - by user306472
    I'm new to javascript and a novice programmer, so this might be a really easy question to answer. I would like to loop over the values of x number of fields and add them up to display the sum in a final field. I can perform this function if I explicitly call each field, but I want to abstract this so I can deal with a flexible number of fields. Here's example code I've come up with (that's not working for me). Where am I going wrong? <html> <head> <script type="text/javascript"> function startAdd(){ interval = setInterval("addfields()",1); } function addfields(){ a = document.addition.total.value; b = getElementByTagName("sum").value; for (i=0; i<=b.length; i++){ a+=i; } return a; } function stopAdd(){ clearInterval(interval); } </script> </head> <body> <form name="addition"> <input type="text" name="sum" onFocus="startAdd();" onBlur="stopAdd;"> + <input type="text" name="sum" onFocus="startAdd();" onBlur="stopAdd;"> = <input type="text" name ="total"> </form> </body> </html>

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  • Using Mergesort to calculate number of inversions in C++

    - by Brown
    void MergeSort(int A[], int n, int B[], int C[]) { if(n > 1) { Copy(A,0,floor(n/2),B,0,floor(n/2)); Copy(A,floor(n/2),n-1,C,0,floor(n/2)-1); MergeSort(B,floor(n/2),B,C); MergeSort(C,floor(n/2),B,C); Merge(A,B,0,floor(n/2),C,0,floor(n/2)-1); } }; void Copy(int A[], int startIndexA, int endIndexA, int B[], int startIndexB, int endIndexB) { while(startIndexA < endIndexA && startIndexB < endIndexB) { B[startIndexB]=A[startIndexA]; startIndexA++; startIndexB++; } }; void Merge(int A[], int B[],int leftp, int rightp, int C[], int leftq, int rightq) //Here each sub array (B and C) have both left and right indices variables (B is an array with p elements and C is an element with q elements) { int i=0; int j=0; int k=0; while(i < rightp && j < rightq) { if(B[i] <=C[j]) { A[k]=B[i]; i++; } else { A[k]=C[j]; j++; inversions+=(rightp-leftp); //when placing an element from the right array, the number of inversions is the number of elements still in the left sub array. } k++; } if(i=rightp) Copy(A,k,rightp+rightq,C,j,rightq); else Copy(A,k,rightp+rightq,B,i,rightp); } I am specifically confused on the effect of the second 'B' and 'C' arguments in the MergeSort calls. I need them in there so I have access to them for Copy and and Merge, but

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  • jquery append 'x' number images elements applying 'x' to src and class

    - by Yusaf
    I have a directory with 590 pictures and my issue is being able to pull images using jquery alone from that directory and appending them which i have found out can not be done alone using jquery/javascript. alternatively i have renamed the pictures 1.jpg,2.jpg ... 590.jpg . how using jquery can i append 590 images to a div leaving me with the number of the appended element applied to the src being 'lq'+numberofappended+'.jpg' and class being 'image-'+numberofappended as a result leaving me with the below <div class="imagecontainer"> <img src="lq/1.jpg" class="image-1"/> <img src="lq/2.jpg" class="image-2"/> <img src="lq/3.jpg" class="image-3"/> ... <img src="lq/590.jpg" class="image-590"/> </div> if what I have will be too extensive can i append 50 images at a time and apply a jquery pagination loading another 50 each time i reach the end of the page. I personally know how to use append in jquery but I don't know how to individually append an image and depending on which append number it is applying it to the src and class.

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  • Find telephonenumbers - finding number with and without an phone extension

    - by nWorx
    Hello there I've a table with about 130 000 records with telephonenumbers. The numbers are all formated like this +4311234567. The numbers always include international country code, local area code and then the phonenumber and sometimes an extension. There is a webservice which checks for the caller's number in the table. That service works already. But now the client wants that also if someone calls from a company which number is already in the database but not his extension, that the service will return some result. Example for table. **id** | **telephonenumber** | **name** | 1 | +431234567 | company A | 2 | +431234567890 | employee in company A | 3 | +4398765432 | company b now if somebody from company A calls with a different extension for example +43123456777, than it should return id1. But the problem is, that I don't know how many digits the extensions have. It could have 3,4 or more digits. Are there any patterns for string kind of matchings? The data is stored in a sql2005 database. Thanks

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  • How to get number of bytes read from QTextStream

    - by user261882
    The following code I am using to find the number of read bytes from QFile. With some files it gives the correct file size, but with some files it gives me a value that is approximatively fileCSV.size()/2. I am sending two files that have same number of characters in it, but have different file sizes link text. Should i use some other objects for reading the QFile? QFile fileCSV("someFile.txt"); if ( !fileCSV.open(QIODevice::ReadOnly | QIODevice::Text)) emit errorOccurredReadingCSV(this); QTextStream textStreamCSV( &fileCSV ); // use a text stream int fileCSVSize = fileCSV.size()); qint64 reconstructedCSVFileSize = 0; while ( !textStreamCSV.atEnd() ) { QString line = textStreamCSV.readLine(); // line of text excluding '\n' if (!line.isEmpty()) { reconstructedCSVFileSize += line.size(); //this doesn't work always reconstructedCSVFileSize += 2; } else reconstructedCSVFileSize += 2; } I know that reading the size of QString is wrong, give me some other solutions if you can. Thank you.

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  • Order words by number of letters, then place words neatly

    - by bmaster
    I have a list of words in javascript similar to this: var words = ["mine", "minute", "mist", "mixed", "money", "monkey", "month", "moon", "morning", "mother", "motion", "mountain", "mouth", "move", "much", "muscle", "music", "nail", "name", "narrow", "nation", "natural", "near", "necessary", "neck", "need", "needle", "nerve", "net", "new", "news", "night"]; The words can be 1-25? letters long. I have a div id="words", with a set width of 700px (but I might change it from this). Using css/javascript/jquery, how can I make it: Order the words by number of letters Place the words inside the div tag, left to right, but so that there are no gaps at the right edge of the words div, and there is even spacing between words on a line. Each word should have a border around it and a background. Like this: |reallylongwordssdf shorterwordfdf dfsdfsdfsdf sdfsdfsdf| |sdfsdfsdf sdffsdop sdfjpogs sdfsds dfsdsd dfsdsd dfsdsd| I really have no idea where to begin with this. Perhaps I could manage to write code to order the words by number of letters, but after that, I'd be stuck. Edit: I forgot to add, the words must be links.

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  • c# warn if text box is empty or contains a non-whole number

    - by Jamaul Smith
    In my specific case, I need the value in propertyPriceTextBox to be numeric only, and a whole number. A value also has to be entered, and I can just Messagebox.Show() a warning and that's all I'd need to do. This is what I have so far. private void computeButton_Click(object sender, EventArgs e) { decimal propertyPrice; if ((decimal.TryParse(propertyPriceTextBox.Text, out propertyPrice))) decimal.Parse(propertyPriceTextBox.Text); { if (residentialRadioButton.Checked == true) commisionLabel.Text = (residentialCom * propertyPrice).ToString("c"); if (commercialRadioButton.Checked == true) commisionLabel.Text = (commercialCom * propertyPrice).ToString("c"); if (hillsRadioButton.Checked == true) countySalesTaxTextBox.Text = ( hilssTax * propertyPrice).ToString("c"); if (pascoRadioButton.Checked == true) countySalesTaxTextBox.Text = (pascoTax * propertyPrice).ToString("c"); if (polkRadioButton.Checked == true) countySalesTaxTextBox.Text = (polkTax * propertyPrice).ToString("c"); decimal result; result = (countySalesTaxTextBox.Text + stateSalesTaxTextBox.Text + propertyPriceTextBox.Text + comissionTextBox.Text).ToString("c"); } else (.) MessageBox.Show("Property Price must be a whole number."); }

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  • Combine Arbitrary number of polygons together

    - by Jakobud
    I have an arbitrary number of polygons (hexes in this case) that are arranged randomly, but they are all touching another hex. Each individual hex has 6 x,y vertices. The vertex's are known for all the hexes. Can anyone point me in the direction of an algorithm that will combine all the hexes into a single polygon? Essentially I'm just looking for a function that spits out an array of vertex locations that are ordered in a way that when drawing lines from one to the next, it forms the polygon. This is my method so far: Create array of all the vertices for all the hexes. Determine the number of times a vertex occurs in the array If vertex is in the array 3+ times, delete the vertices from the array. If vertex is in the array 2 times, delete one of them. The next step is tricky though. I'm using canvas to draw out these polygons, which essentially involves drawing a line from one vertex to the next. So the order of the vertices in the final array is important. It can't be sorted arbitrarily. Also, I'm not looking for a "convex hull" algorithm, as that would not draw the polygon correctly. Are there any functions out there that do something like this? Am I on the right track or is there a better more efficient way?

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  • Validating a phone number in Android PreferenceScreen

    - by djechelon
    I have a PreferenceScreen in which the user is capable, if system can't autodetect it, to enter the device's phone number. I'm still learning this part of Android but I managed to understand a bit of PreferenceScreens by examples provided by Android SDK itself and a few tutorials. What I want is that the user can save the phone number only if null or valid, where by "valid" I mean running a generic validation logic (ie. an anonymous method that returns true or false, that can be reused in any possible situation*) or better, just to simplify things, ^(\+39)?3[0-9]{9}$ For now I have the following XML snip <EditTextPreference android:inputType="phone" android:key="@string/preference_phoneNo" android:selectAllOnFocus="true" android:singleLine="true" android:summary="@string/pref_phoneNumber_description" android:title="@string/pref_phoneNumber" /> and following code by courtesy of Eclipse New Activity wizard: private void setupSimplePreferencesScreen() { if (!isSimplePreferences(this)) { return; } addPreferencesFromResource(R.xml.pref_general); bindPreferenceSummaryToValue(findPreference(getString(R.string.preference_phoneNo))); } addPreferenceFromResource is supposed to load the XML node and add the preference to the screen, while binPreferenceSummaryToValue is supposed to make description text change when preference is updated. Just for sake of completeness for those who don't like code courtesy of the IDE, the second method is provided by Eclipse who also provides a private class in the code file that is /** * A preference value change listener that updates the preference's summary * to reflect its new value. */ In the general case, what should I do to perform validation logic before the preference gets saved when I click OK on the preference editor? Where is the validation logic to be put in a PreferenceScreen? *Aren't we all here to learn?

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  • Adding up row number and displaying total using COUNT (PHP MySQL)

    - by Yvonne
    I'm attempting to run a query that adds up the total number of subjects in a class. A class has many subjects. There is a 'teachersclasses' table between teachers (the user table) and classes. The principles sounds pretty simple but I'm having some trouble in getting my page to display the number of subjects for each class (directly associated with the teacher) This is what I have so far, trying to make use of the COUNT with a nested SELECT: SELECT (SELECT count(*) FROM subjects WHERE subjects.classid = class.classid) AS total_subjects, class.classname, class.classid FROM class Then I am calling up 'num_subjects' to present the total within a while loop: <?php echo $row['total_subjects']?> From the above, I am receiving the total subjects for a class, but within the same table row (for one class) and my other while loop doesnt run anymore, which returns all of the classes associated with a teacher :( ... Bit of a mess now! I know to return the classes for a particular teacher, I can do an additional WHERE clause on the session of 'teacherid' but I think my query is getting too complicated for me that errors are popping up everywhere. Anyone have a quick fix for this! Thanks very much

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  • MVC HTML.RenderAction – Error: Duration must be a positive number

    - by BarDev
    On my website I want the user to have the ability to login/logout from any page. When the user select login button a modal dialog will be present to the user for him to enter in his credentials. Since login will be on every page, I thought I would create a partial view for the login and add it to the layout page. But when I did this I got the following error: Exception Details: System.InvalidOperationException: Duration must be a positive number. There are other ways to work around this that would not using partial views, but I believe this should work. So to test this, I decided to make everything simple with the following code: Created a layout page with the following code @{Html.RenderAction("_Login", "Account");} In the AccountController: public ActionResult _Login() { return PartialView("_Login"); } Partial View _Login <a id="signin">Login</a> But when I run this simple version this I still get this error: Exception Details: System.InvalidOperationException: Duration must be a positive number. Source of error points to "@{Html.RenderAction("_Login", "Account");}" There are some conversations on the web that are similar to my problem, which identifies this as bug with MVC (see links below). But the links pertain to Caching, and I'm not doing any caching. OuputCache Cache Profile does not work for child actions http://aspnet.codeplex.com/workitem/7923 Asp.Net MVC 3 Partial Page Output Caching Not Honoring Config Settings Asp.Net MVC 3 Partial Page Output Caching Not Honoring Config Settings Caching ChildActions using cache profiles won't work? Caching ChildActions using cache profiles won't work? I'm not sure if this makes a difference, but I'll go ahead and add it here. I'm using MVC 3 with Razor. Update Stack Trace [InvalidOperationException: Duration must be a positive number.] System.Web.Mvc.OutputCacheAttribute.ValidateChildActionConfiguration() +624394 System.Web.Mvc.OutputCacheAttribute.OnActionExecuting(ActionExecutingContext filterContext) +127 System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func1 continuation) +72 System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func1 continuation) +784922 System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList1 filters, ActionDescriptor actionDescriptor, IDictionary2 parameters) +314 System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +784976 System.Web.Mvc.Controller.ExecuteCore() +159 System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +335 System.Web.Mvc.<c_DisplayClassb.b_5() +62 System.Web.Mvc.Async.<c_DisplayClass1.b_0() +20 System.Web.Mvc.<c_DisplayClasse.b_d() +54 System.Web.Mvc.<c_DisplayClass4.b_3() +15 System.Web.Mvc.ServerExecuteHttpHandlerWrapper.Wrap(Func`1 func) +41 System.Web.HttpServerUtility.ExecuteInternal(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage, VirtualPath path, VirtualPath filePath, String physPath, Exception error, String queryStringOverride) +1363 [HttpException (0x80004005): Error executing child request for handler 'System.Web.Mvc.HttpHandlerUtil+ServerExecuteHttpHandlerAsyncWrapper'.] System.Web.HttpServerUtility.ExecuteInternal(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage, VirtualPath path, VirtualPath filePath, String physPath, Exception error, String queryStringOverride) +2419 System.Web.HttpServerUtility.Execute(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage) +275 System.Web.HttpServerUtilityWrapper.Execute(IHttpHandler handler, TextWriter writer, Boolean preserveForm) +94 System.Web.Mvc.Html.ChildActionExtensions.ActionHelper(HtmlHelper htmlHelper, String actionName, String controllerName, RouteValueDictionary routeValues, TextWriter textWriter) +838 System.Web.Mvc.Html.ChildActionExtensions.RenderAction(HtmlHelper htmlHelper, String actionName, String controllerName, RouteValueDictionary routeValues) +56 ASP._Page_Views_Shared_SiteLayout_cshtml.Execute() in c:\Projects\Odat Projects\Odat\Source\Presentation\Odat.PublicWebSite\Views\Shared\SiteLayout.cshtml:80 System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +280 System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +104 System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +173 System.Web.WebPages.WebPageBase.Write(HelperResult result) +89 System.Web.WebPages.WebPageBase.RenderSurrounding(String partialViewName, Action1 body) +234 System.Web.WebPages.WebPageBase.PopContext() +234 System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +384 System.Web.Mvc.<>c__DisplayClass1c.<InvokeActionResultWithFilters>b__19() +33 System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func1 continuation) +784900 System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func1 continuation) +784900 System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList1 filters, ActionResult actionResult) +265 System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +784976 System.Web.Mvc.Controller.ExecuteCore() +159 System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +335 System.Web.Mvc.<c_DisplayClassb.b_5() +62 System.Web.Mvc.Async.<c_DisplayClass1.b_0() +20 System.Web.Mvc.<c_DisplayClasse.b_d() +54 System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +453 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +371 Update When I Break in Code, it errors at @{Html.RenderAction("_Login", "Account");} with the following exception. The inner exception Error executing child request for handler 'System.Web.Mvc.HttpHandlerUtil+ServerExecuteHttpHandlerAsyncWrapper'. at System.Web.HttpServerUtility.ExecuteInternal(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage, VirtualPath path, VirtualPath filePath, String physPath, Exception error, String queryStringOverride) at System.Web.HttpServerUtility.Execute(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage) at System.Web.HttpServerUtilityWrapper.Execute(IHttpHandler handler, TextWriter writer, Boolean preserveForm) at System.Web.Mvc.Html.ChildActionExtensions.ActionHelper(HtmlHelper htmlHelper, String actionName, String controllerName, RouteValueDictionary routeValues, TextWriter textWriter) at System.Web.Mvc.Html.ChildActionExtensions.RenderAction(HtmlHelper htmlHelper, String actionName, String controllerName, RouteValueDictionary routeValues) at ASP._Page_Views_Shared_SiteLayout_cshtml.Execute() in c:\Projects\Odat Projects\Odat\Source\Presentation\Odat.PublicWebSite\Views\Shared\SiteLayout.cshtml:line 80 at System.Web.WebPages.WebPageBase.ExecutePageHierarchy() at System.Web.Mvc.WebViewPage.ExecutePageHierarchy() at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) at System.Web.WebPages.WebPageBase.Write(HelperResult result) at System.Web.WebPages.WebPageBase.RenderSurrounding(String partialViewName, Action1 body) at System.Web.WebPages.WebPageBase.PopContext() at System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass1c.<InvokeActionResultWithFilters>b__19() at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func1 continuation) Answer Thanks Darin Dimitrov Come to find out, my AccountController had the following attribute [System.Web.Mvc.OutputCache(NoStore =true, Duration = 0, VaryByParam = "*")]. I don't believe this should caused a problem, but when I removed the attribute everything worked. BarDev

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  • Ruby number_to_currency displays a totally wrong number!

    - by SueP
    Greetings! I’m an old Delphi programmer making the leap to the Mac, Ruby, Rails, and web programming in general. I’m signed up for the Advanced Rails workshop at the end of the month. In the meantime, I’ve been working on porting a mission-critical (of course) app from Delphi to RAILS. It feels like I’ve spent most of the past year with my head buried in a book or podcast. Right now, I’ve hit a major issue and I’m tearing my hair out. I literally don’t know where to go with this, I desperately don’t want to deploy with this bug, and I’m feeling a bit frantic. (The company database is currently running on an ancient XP box that’s looking rustier by the day.) So, I set up a test database that shows the problem. I’m running: OS/X 10.6.3 Rails 2.3.5 ruby 1.8.7 (2009-06-08 patchlevel 173) [universal-darwin10.0] MySQL 5.1.38-log via socket MySQL Client Version 5.1.8 ActiveRecord::Schema.define(:version => 20100406222528) do create_table “money”, :force => true do |t| t.decimal “amount_due”, :precision => 10, :scale => 2, :default => 0.0 t.decimal “balance”, :precision => 10, :scale => 2, :default => 0.0 t.text “memofield” t.datetime “created_at” t.datetime “updated_at” end The index view is right out of the generator, slightly modified to add the formatting that's breaking on me. Listing money <table> <tr> <th>Amount</th> <th>Amount to_s </th> <th>Balance to $</th> <th>Balance with_precision </th> <th>Memofield</th> </tr> <% @money.each do |money| %> <tr> <td><%=h money.amount_due %></td> <td><%=h money.amount_due.to_s(‘F’) %></td> <td><%=h number_to_currency(money.balance) %></td> <td><%=h number_with_precision(money.balance, :precision => 2) %></td> <td><%=h money.memofield %></td> <td><%= link_to ‘Show’, money %></td> <td><%= link_to ‘Edit’, edit_money_path(money) %></td> <td><%= link_to ‘Destroy’, money, :confirm => ‘Are you sure?’, :method => :delete %></td> </tr> *<% end %> *</table> <%= link_to ‘New money’, new_money_path %> This seemed to work pretty well. Then I started testing with production data and hit a major problem with number_to_currency. The number in the database is: 10542.28, I verified it with the MySQL Query Browser. RAILS will display this as 10542.28 unless I call number_to_currency, then that number is displayed as: $15422.80 The error seems to happen with any number between 10,000.00 and 10,999.99 So far, I haven’t seen it outside of that range, but I obviously haven’t tested everything. I guess my workaround is to remove number_to_currency, but that leaves the views looking really sloppy and unprofessional. The formatting is messed up, things don’t line up properly and I can’t force the display to 2 decimal places. I’m seriously hoping there is an easy fix for this. I can’t imagine this being a widespread problem. It would affect so many people that someone would have fixed it! But I don’t know where to go from here. I’d desperately like some help. (Later – number_with_precision fails the same way number_to_currency does.) Sue Petersen

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  • Performance considerations for common SQL queries

    - by Jim Giercyk
    Originally posted on: http://geekswithblogs.net/NibblesAndBits/archive/2013/10/16/performance-considerations-for-common-sql-queries.aspxSQL offers many different methods to produce the same results.  There is a never-ending debate between SQL developers as to the “best way” or the “most efficient way” to render a result set.  Sometimes these disputes even come to blows….well, I am a lover, not a fighter, so I decided to collect some data that will prove which way is the best and most efficient.  For the queries below, I downloaded the test database from SQLSkills:  http://www.sqlskills.com/sql-server-resources/sql-server-demos/.  There isn’t a lot of data, but enough to prove my point: dbo.member has 10,000 records, and dbo.payment has 15,554.  Our result set contains 6,706 records. The following queries produce an identical result set; the result set contains aggregate payment information for each member who has made more than 1 payment from the dbo.payment table and the first and last name of the member from the dbo.member table.   /*************/ /* Sub Query  */ /*************/ SELECT  a.[Member Number] ,         m.lastname ,         m.firstname ,         a.[Number Of Payments] ,         a.[Average Payment] ,         a.[Total Paid] FROM    ( SELECT    member_no 'Member Number' ,                     AVG(payment_amt) 'Average Payment' ,                     SUM(payment_amt) 'Total Paid' ,                     COUNT(Payment_No) 'Number Of Payments'           FROM      dbo.payment           GROUP BY  member_no           HAVING    COUNT(Payment_No) > 1         ) a         JOIN dbo.member m ON a.[Member Number] = m.member_no         /***************/ /* Cross Apply  */ /***************/ SELECT  ca.[Member Number] ,         m.lastname ,         m.firstname ,         ca.[Number Of Payments] ,         ca.[Average Payment] ,         ca.[Total Paid] FROM    dbo.member m         CROSS APPLY ( SELECT    member_no 'Member Number' ,                                 AVG(payment_amt) 'Average Payment' ,                                 SUM(payment_amt) 'Total Paid' ,                                 COUNT(Payment_No) 'Number Of Payments'                       FROM      dbo.payment                       WHERE     member_no = m.member_no                       GROUP BY  member_no                       HAVING    COUNT(Payment_No) > 1                     ) ca /********/                    /* CTEs  */ /********/ ; WITH    Payments           AS ( SELECT   member_no 'Member Number' ,                         AVG(payment_amt) 'Average Payment' ,                         SUM(payment_amt) 'Total Paid' ,                         COUNT(Payment_No) 'Number Of Payments'                FROM     dbo.payment                GROUP BY member_no                HAVING   COUNT(Payment_No) > 1              ),         MemberInfo           AS ( SELECT   p.[Member Number] ,                         m.lastname ,                         m.firstname ,                         p.[Number Of Payments] ,                         p.[Average Payment] ,                         p.[Total Paid]                FROM     dbo.member m                         JOIN Payments p ON m.member_no = p.[Member Number]              )     SELECT  *     FROM    MemberInfo /************************/ /* SELECT with Grouping   */ /************************/ SELECT  p.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         COUNT(Payment_No) 'Number Of Payments' ,         AVG(payment_amt) 'Average Payment' ,         SUM(payment_amt) 'Total Paid' FROM    dbo.payment p         JOIN dbo.member m ON m.member_no = p.member_no GROUP BY p.member_no ,         m.lastname ,         m.firstname HAVING  COUNT(Payment_No) > 1   We can see what is going on in SQL’s brain by looking at the execution plan.  The Execution Plan will demonstrate which steps and in what order SQL executes those steps, and what percentage of batch time each query takes.  SO….if I execute all 4 of these queries in a single batch, I will get an idea of the relative time SQL takes to execute them, and how it renders the Execution Plan.  We can settle this once and for all.  Here is what SQL did with these queries:   Not only did the queries take the same amount of time to execute, SQL generated the same Execution Plan for each of them.  Everybody is right…..I guess we can all finally go to lunch together!  But wait a second, I may not be a fighter, but I AM an instigator.     Let’s see how a table variable stacks up.  Here is the code I executed: /********************/ /*  Table Variable  */ /********************/ DECLARE @AggregateTable TABLE     (       member_no INT ,       AveragePayment MONEY ,       TotalPaid MONEY ,       NumberOfPayments MONEY     ) INSERT  @AggregateTable         SELECT  member_no 'Member Number' ,                 AVG(payment_amt) 'Average Payment' ,                 SUM(payment_amt) 'Total Paid' ,                 COUNT(Payment_No) 'Number Of Payments'         FROM    dbo.payment         GROUP BY member_no         HAVING  COUNT(Payment_No) > 1   SELECT  at.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         at.NumberOfPayments 'Number Of Payments' ,         at.AveragePayment 'Average Payment' ,         at.TotalPaid 'Total Paid' FROM    @AggregateTable at         JOIN dbo.member m ON m.member_no = at.member_no In the interest of keeping things in groupings of 4, I removed the last query from the previous batch and added the table variable query.  Here’s what I got:     Since we first insert into the table variable, then we read from it, the Execution Plan renders 2 steps.  BUT, the combination of the 2 steps is only 22% of the batch.  It is actually faster than the other methods even though it is treated as 2 separate queries in the Execution Plan.  The argument I often hear against Table Variables is that SQL only estimates 1 row for the table size in the Execution Plan.  While this is true, the estimate does not come in to play until you read from the table variable.  In this case, the table variable had 6,706 rows, but it still outperformed the other queries.  People argue that table variables should only be used for hash or lookup tables.  The fact is, you have control of what you put IN to the variable, so as long as you keep it within reason, these results suggest that a table variable is a viable alternative to sub-queries. If anyone does volume testing on this theory, I would be interested in the results.  My suspicion is that there is a breaking point where efficiency goes down the tubes immediately, and it would be interesting to see where the threshold is. Coding SQL is a matter of style.  If you’ve been around since they introduced DB2, you were probably taught a little differently than a recent computer science graduate.  If you have a company standard, I strongly recommend you follow it.    If you do not have a standard, generally speaking, there is no right or wrong answer when talking about the efficiency of these types of queries, and certainly no hard-and-fast rule.  Volume and infrastructure will dictate a lot when it comes to performance, so your results may vary in your environment.  Download the database and try it!

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