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• Servlet response wrapper has encoding problem

  - by John O

  A servlet response wrapper is being used in a Servlet Filter. The idea is that the response is manipulated, with a 'nonce' value being injected into forms, as part of defence against CSRF attacks. The web app is using UTF-8 everywhere. When the Servlet Filter is absent, no problems. When the filter is added, encoding issues occur. (It seems as if the response is reverting to 8859-1.) The guts of the code : final class CsrfResponseWrapper extends AbstractResponseWrapper { ... byte[] modifyResponse(byte[] aInputResponse){ ... String originalInput = new String(aInputResponse, encoding); String modifiedResult = addHiddenParamToPostedForms(originalInput); result = modifiedResult.getBytes(encoding); ... } ... } As I understand it, the transition between byte-land and String-land should specify an encoding. That is done here, as you can see, in two places. The value of the 'encoding' variable is 'UTF-8'; the alteration of the String itself is standard string manipulation (with a regex), and never specifies an encoding (addHiddenParamToPostedForms). Where am I in error about the encoding? EDIT: Here is the base class (sorry it's rather long): package hirondelle.web4j.security; import javax.servlet.ServletOutputStream; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpServletResponseWrapper; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.PrintWriter; /** Abstract Base Class for altering response content. (May be useful in future contexts as well. For now, keep package-private.) */ abstract class AbstractResponseWrapper extends HttpServletResponseWrapper { AbstractResponseWrapper(ServletResponse aServletResponse) throws IOException { super((HttpServletResponse)aServletResponse); fOutputStream = new ModifiedOutputStream(aServletResponse.getOutputStream()); fWriter = new PrintWriter(fOutputStream); } /** Return the modified response. */ abstract byte[] modifyResponse(byte[] aInputResponse); /** Standard servlet method. */ public final ServletOutputStream getOutputStream() { //fLogger.fine("Modified Response : Getting output stream."); if ( fWriterReturned ) { throw new IllegalStateException(); } fOutputStreamReturned = true; return fOutputStream; } /** Standard servlet method. */ public final PrintWriter getWriter() { //fLogger.fine("Modified Response : Getting writer."); if ( fOutputStreamReturned ) { throw new IllegalStateException(); } fWriterReturned = true; return fWriter; } // PRIVATE /* Well-behaved servlets return either an OutputStream or a PrintWriter, but not both. */ private PrintWriter fWriter; private ModifiedOutputStream fOutputStream; /* These items are used to implement conformance to the javadoc for ServletResponse, regarding exceptions being thrown. */ private boolean fWriterReturned; private boolean fOutputStreamReturned; /** Modified low level output stream. */ private class ModifiedOutputStream extends ServletOutputStream { public ModifiedOutputStream(ServletOutputStream aOutputStream) { fServletOutputStream = aOutputStream; fBuffer = new ByteArrayOutputStream(); } /** Must be implemented to make this class concrete. */ public void write(int aByte) { fBuffer.write(aByte); } public void close() throws IOException { if ( !fIsClosed ){ processStream(); fServletOutputStream.close(); fIsClosed = true; } } public void flush() throws IOException { if ( fBuffer.size() != 0 ){ if ( !fIsClosed ) { processStream(); fBuffer = new ByteArrayOutputStream(); } } } /** Perform the core processing, by calling the abstract method. */ public void processStream() throws IOException { fServletOutputStream.write(modifyResponse(fBuffer.toByteArray())); fServletOutputStream.flush(); } // PRIVATE // private ServletOutputStream fServletOutputStream; private ByteArrayOutputStream fBuffer; /** Tracks if this stream has been closed. */ private boolean fIsClosed = false; } }

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• How to manipulate data after its retrieved via remote database

  - by bMon

  So I've used code examples from all over the net and got my app to accurately call a .php file on my server, retrieve the JSON data, then parse the data, and print it. The problem is that its just printing to the screen for sake of the tutorial I was following, but now I need to use that data in other places and need help figuring out that process. The ultimate goal is to return my db query with map coordinates, then plot them on a google map. I have another app in which I manually plot points on a map, so I'll be integrating this app with that once I can get my head around how to correctly manipulate the data returned. public class Remote extends Activity { /** Called when the activity is first created. */ TextView txt; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // Create a crude view - this should really be set via the layout resources // but since its an example saves declaring them in the XML. LinearLayout rootLayout = new LinearLayout(getApplicationContext()); txt = new TextView(getApplicationContext()); rootLayout.addView(txt); setContentView(rootLayout); // Set the text and call the connect function. txt.setText("Connecting..."); //call the method to run the data retreival txt.setText(getServerData(KEY_121)); } public static final String KEY_121 = "http://example.com/mydbcall.php"; private String getServerData(String returnString) { InputStream is = null; String result = ""; //the year data to send //ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(); //nameValuePairs.add(new BasicNameValuePair("year","1970")); try{ HttpClient httpclient = new DefaultHttpClient(); HttpPost httppost = new HttpPost(KEY_121); HttpResponse response = httpclient.execute(httppost); HttpEntity entity = response.getEntity(); is = entity.getContent(); }catch(Exception e){ Log.e("log_tag", "Error in http connection "+e.toString()); } //convert response to string try{ BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } is.close(); result=sb.toString(); }catch(Exception e){ Log.e("log_tag", "Error converting result "+e.toString()); } //parse json data try{ JSONArray jArray = new JSONArray(result); for(int i=0;i<jArray.length();i++){ JSONObject json_data = jArray.getJSONObject(i); Log.i("log_tag","longitude: "+json_data.getDouble("longitude")+ ", latitude: "+json_data.getDouble("latitude") ); //Get an output to the screen returnString += "\n\t" + jArray.getJSONObject(i); } }catch(JSONException e){ Log.e("log_tag", "Error parsing data "+e.toString()); } return returnString; } } So the code: returnString += "\n\t" + jArray.getJSONObject(i); is what is currently printing to the screen. What I have to figure out is how to get the data into something I can reference in other spots in the program, and access the individual elements ie: double longitude = jArray.getJSONObject(3).longitude; or something to that effect.. I figure the class getServerData will have to return a Array type or something? Any help is appreciated, thanks.

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• Delaying execution of Javascript function relative to Google Maps / geoxml3 parser?

  - by Terra Fimeira

  I'm working on a implementing a Google map on a website with our own tiles overlays and KML elements. I've been previously requested to create code so that, for instance, when the page is loaded from a specific URL, it would initialize with one of the tile overlays already enabled. Recently, I've been requested to do the same for the buildings which are outlined by KML elements so that, arriving at the page with a specific URL, it would automatically zoom, center, and display information on the building. However, while starting with the tile overlays work, the building KML does not. After doing some testing, I've determined that when the code which checks the URL executes, the page is still loading the KML elements and thus do not exist for the code to compare to or use: Code for evaluating URL (placed at the end of onLoad="initialize()") function urlClick() { var currentURL = window.location.href; //Retrieve page URL var URLpiece = currentURL.slice(-6); //pull the last 6 digits (for testing) if (URLpiece === "access") { //If the resulting string is "access": access_click(); //Display accessibility overlay } else if (URLpiece === "middle") { //Else if the string is "middle": facetClick('Middle College'); //Click on building "Middle College" }; }; facetClick(); function facetClick(name) { //Convert building name to building ID. for (var i = 0; i < active.placemarks.length; i++) { if (active.placemarks[i].name === name) { sideClick(i) //Click building whose id matches "Middle College" }; }; }; Firebug Console Error active is null for (var i = 0; i < active.placemarks.length; i++) { active.placemarks is which KML elements are loaded on the page, and being null, means no KML has been loaded yet. In short, I have a mistiming and I can't seem to find a suitable place to place the URL code to execute after the KMl has loaded. As noted above, I placed it at the end of onLoad="initialize()", but it would appear that, instead of waiting for the KML to completely load earlier in the function, the remainder of the function is executed: onLoad="initialize()" information(); //Use the buttons variables inital state to set up description buttons(); //and button state button_hover(0); //and button description to neutral. //Create and arrange the Google Map. //Create basic tile overlays. //Set up parser to work with KML elements. myParser = new geoXML3.parser({ //Parser: Takes KML and converts to JS. map: map, //Applies parsed KML to the map singleInfoWindow: true, afterParse: useTheData //Allows us to use the parsed KML in a function }); myParser.parse(['/maps/kml/shapes.kml','/maps/kml/shapes_hidden.kml']); google.maps.event.addListener(map, 'maptypeid_changed', function() { autoOverlay(); }); //Create other tile overlays to appear over KML elements. urlClick(); I suspect one my issues lies in using the geoxml3 parser (http://code.google.com/p/geoxml3/) which converts our KML files to Javascript. While the page has completed loading all of the elements, the map on the page is still loading, including the KML elements. I have also tried placing urlClick() in the parser itself in various places which appear to execute after all the shapes have been parsed, but I've had no success there either. While I've been intending to strip out the parser, I would like to know if there is any way of executing the "urlClick" after the parser has returned the KML shapes. Ideally, I don't want to use an arbitrary means of defining a time to wait, such as "wait 3 seconds, and go", as my various browsers all load the page at different times; rather, I'm looking for some way to say "when the parser is done, execute" or "when the Google map is completely loaded, execute" or perhaps even "hold until the parser is complete before advancing to urlClick".

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• XForms and multiple inputs for same model tag

  - by iHeartGreek

  Hi! I apologize ahead of time if I am not asking this properly.. it is hard to put into words what I am asking.. I have XForms model such as: <file> <criteria> <criterion></criterion> </criteria> </file> I want to have multiple input text boxes that create a new criterion tag. user interface such as: <xf:input ref="/file/criteria/criterion" model="select_data"> <xf:label>Select</xf:label> </xf:input> <xf:input ref="/file/criteria/criterion" model="select_data"> <xf:label>Select</xf:label> </xf:input> <xf:input ref="/file/criteria/criterion" model="select_data"> <xf:label>Select</xf:label> </xf:input> And I would like the XML output to look like this (once user has entered in info): <file> <criteria> <criterion>AAA</criterion> <criterion>BBB</criterion> <criterion>CCC</criterion> </criteria> </file> The way I have it doesn't work, as it sees the 3 input fields to be referring all to the same criterion tag. How do I differentiate? Thanks! I hope that made some sense! BEGIN FIRST EDIT Thanks for the responses for the basic text box! However, I now need to do this with a listbox. But for the life of me, I can't figure out how. I read somewhere to use with the xforms:select and deselect events.. but I didn't know where to place them, and the places I tried gave me very weird behaviour. I am currently implementing the following: <xf:select ref="instance('criteria_data')/criteria/criterion" selection="" appearance="compact" > <xf:label>Choose criteria</xf:label> <xf:itemset nodeset="instance('criteria_choices')/choice"> <xf:label ref="@label"></xf:label> <xf:value ref="."></xf:value> </xf:itemset> </xf:select> However when multiple choices are submitted, all selection values are inserted into the same node, separated by spaces. For example: If AAA and BBB and FFF were selected from listbox, it would result in the following XML: <criterion>AAA BBB FFF</criterion> How do I change my code to have each selection be in a separate node? i.e. I want it to look like this: <criterion>AAA</criterion> <criterion>BBB</criterion> <criterion>FFF</criterion> Thanks! END FIRST EDIT BEGIN SECOND EDIT: For the listboxes (ie xf:select appearance="compact") I ended up allowing the spaces to occur in the same node and then just transformed that xml using xsl to generate a properly formatted new xml doc (with separate individual nodes). Unfortunately, I did not find a less cumbersome solution by inserting them originally into separate nodes. The selected answer works very well for text boxes however, hence why I selected it as the answer. END SECOND EDIT

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• HMTL5 Anti Aliasing Browser Disable

  - by Tappa Tappa

  I am forced to consider writing a library to handle the fundamental basics of drawing lines, thick lines, circles, squares etc. of an HTML5 canvas because I can't disable a feature embedded in the browser rendering of the core canvas algorithms. Am I forced to build the HTML5 Canvas rendering process from the ground up? If I am, who's in with me to do this? Who wants to change the world? Imagine a simple drawing application written in HTML5... you draw a shape... a closed shape like a rudimentary circle, free hand, more like an onion than a circle (well, that's what mine would look like!)... then imagine selecting a paint bucket icon and clicking inside that shape you drew and expecting it to be filled with a color of your choice. Imagine your surprise as you selected "Paint Bucket" and clicked in the middle of your shape and it filled your shape with color... BUT, not quite... HANG ON... this isn't right!!! On the inside of the edge of the shape you drew is a blur between the background color and your fill color and the edge color... the fill seems to be flawed. You wanted a straight forward "Paint Bucket" / "Fill"... you wanted to draw a shape and then fill it with a color... no fuss.... fill the whole damned inside of your shape with the color you choose. Your web browser has decided that when you draw the lines to define your shape they will be anti-aliased. If you draw a black line for your shape... well, the browser will draw grey pixels along the edges, in places... to make it look like a "better" line. Yeah, a "better" line that **s up the paint / flood fill process. How much does is cost to pay off the browser developers to expose a property to disable their anti-aliasing rendering? Disabling would save milliseconds for their rendering engine, surely! Bah, I really don't want to have to build my own canvas rendering engine using Bresenham line rendering algorithm... WHAT CAN BE DONE... HOW CAN THIS BE CHANGED!!!??? Do I need to start a petition aimed at the WC3???? Will you include your name if you are interested??? UPDATED function DrawLine(objContext, FromX, FromY, ToX, ToY) { var dx = Math.abs(ToX - FromX); var dy = Math.abs(ToY - FromY); var sx = (FromX < ToX) ? 1 : -1; var sy = (FromY < ToY) ? 1 : -1; var err = dx - dy; var CurX, CurY; CurX = FromX; CurY = FromY; while (true) { objContext.fillRect(CurX, CurY, objContext.lineWidth, objContext.lineWidth); if ((CurX == ToX) && (CurY == ToY)) break; var e2 = 2 * err; if (e2 > -dy) { err -= dy; CurX += sx; } if (e2 < dx) { err += dx; CurY += sy; } } }

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• displaying search results of more than one word

  - by fusion

  in my search form, if the user types 'good', it displays all the results which contain the keyword 'good'. however if the user types in 'good sweetest', it displays no results because there is no record with the two words appearing together; BUT appearing in an entry at different places. for example, the record says: A good action is an ever-remaining store and a pure yield the user types in 'good', it will show up this record, but if the user types in 'good' + 'pure', it will not show anything. or if the record contains the keyword 'good-deeds' and if the user types in 'good deeds' without the hyphen, it will not show anything. what i would like is that if the user types in 'good' + 'pure' or 'good deeds' it should records containing these keywords highlighting them. search.php code: $search_result = ""; $search_result = $_POST["q"]; $search_result = trim($search_result); //Check if the string is empty if ($search_result == "") { echo "<p class='error'>Search Error. Please Enter Your Search Query.</p>" ; exit(); } if ($search_result == "%" || $search_result == "_" || $search_result == "+" ) { echo "<p class='error1'>Search Error. Please Enter a Valid Search Query.</p>" ; exit(); } $result = mysql_query('SELECT cQuotes, vAuthor, cArabic, vReference FROM thquotes WHERE cQuotes LIKE "%' . mysql_real_escape_string($search_result) .'%" ORDER BY idQuotes DESC', $conn) or die ('Error: '.mysql_error()); function h($s) { echo htmlspecialchars($s, ENT_QUOTES); } function highlightWords($string, $word) { $string = preg_replace("/".preg_quote($word, "/")."/i", "<span class='highlight'>$0</span>", $string); /*** return the highlighted string ***/ return $string; } ?> <div class="caption">Search Results</div> <div class="center_div"> <table> <?php while ($row= mysql_fetch_array($result, MYSQL_ASSOC)) { $cQuote = highlightWords(htmlspecialchars($row['cQuotes']), $search_result); ?> <tr> <td style="text-align:right; font-size:18px;"><?php h($row['cArabic']); ?></td> <td style="font-size:16px;"><?php echo $cQuote; ?></td> <td style="font-size:12px;"><?php h($row['vAuthor']); ?></td> <td style="font-size:12px; font-style:italic; text-align:right;"><?php h($row['vReference']); ?></td> </tr> <?php } ?> </table> </div> search.html: <form name="myform" class="wrapper"> <input type="text" name="q" onkeyup="showUser()" class="txt_search"/> <input type="button" name="button" onclick="showUser()" class="button"/> <p> <div id="txtHint"></div> </form>

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• Alphabetically Ordering an array of words

  - by Genesis

  I'm studying C on my own in preparation for my upcoming semester of school and was wondering what I was doing wrong with my code so far. If Things look weird it is because this is part of a much bigger grab bag of sorting functions I'm creating to get a sense of how to sort numbers,letters,arrays,and the like! I'm basically having some troubles with the manipulation of strings in C currently. Also, I'm quite limited in my knowledge of C at the moment! My main Consists of this: #include <stdio.h> #include <stdio.h> #include <stdlib.h> int numbers[10]; int size; int main(void){ setvbuf(stdout,NULL,_IONBF,0); //This is magical code that allows me to input. int wordNumber; int lengthOfWord = 50; printf("How many words do you want to enter: "); scanf("%i", &wordNumber); printf("%i\n",wordNumber); char words[wordNumber][lengthOfWord]; printf("Enter %i words:",wordNumber); int i; for(i=0;i<wordNumber+1;i++){ //+1 is because my words[0] is blank. fgets(&words[i], 50, stdin); } for(i=1;i<wordNumber+1;i++){ // Same as the above comment! printf("%s", words[i]); //prints my words out! } alphabetize(words,wordNumber); //I want to sort these arrays with this function. } My sorting "method" I am trying to construct is below! This function is seriously flawed, but I'd thought I'd keep it all to show you where my mind was headed when writing this. void alphabetize(char a[][],int size){ // This wont fly. size = size+1; int wordNumber; int lengthOfWord; char sortedWords[wordNumber][lengthOfWord]; //In effort for the for loop int i; int j; for(i=1;i<size;i++){ //My effort to copy over this array for manipulation for(j=1;j<size;j++){ sortedWords[i][j] = a[i][j]; } } //This should be kinda what I want when ordering words alphabetically, right? for(i=1;i<size;i++){ for(j=2;j<size;j++){ if(strcmp(sortedWords[i],sortedWords[j]) > 0){ char* temp = sortedWords[i]; sortedWords[i] = sortedWords[j]; sortedWords[j] = temp; } } } for(i=1;i<size;i++){ printf("%s, ",sortedWords[i]); } } I guess I also have another question as well... When I use fgets() it's doing this thing where I get a null word for the first spot of the array. I have had other issues recently trying to scanf() char[] in certain ways specifically spacing my input word variables which "magically" gets rid of the first null space before the character. An example of this is using scanf() to write "Hello" and getting " Hello" or " ""Hello"... Appreciate any thoughts on this, I've got all summer to study up so this doesn't need to be answered with haste! Also, thank you stack overflow as a whole for being so helpful in the past. This may be my first post, but I have been a frequent visitor for the past couple of years and it's been one of the best places for helpful advice/tips.

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• displaying search results with two or more queries

  - by fusion

  in my search form, if the user types 'good', it displays all the results which contain the keyword 'good'. however if the user types in 'good sweetest', it displays no results because there is no record with the two words appearing together; BUT appearing in an entry at different places. for example, the record says: A good action is an ever-remaining store and a pure yield the user types in 'good', it will show up this record, but if the user types in 'good' + 'pure', it will not show anything. what i would like is that if the user types in 'good' + 'pure' it should records containing these keywords highlighting them. search.php code: $search_result = ""; $search_result = $_POST["q"]; $search_result = trim($search_result); //Check if the string is empty if ($search_result == "") { echo "<p class='error'>Search Error. Please Enter Your Search Query.</p>" ; exit(); } if ($search_result == "%" || $search_result == "_" || $search_result == "+" ) { echo "<p class='error1'>Search Error. Please Enter a Valid Search Query.</p>" ; exit(); } $result = mysql_query('SELECT cQuotes, vAuthor, cArabic, vReference FROM thquotes WHERE cQuotes LIKE "%' . mysql_real_escape_string($search_result) .'%" ORDER BY idQuotes DESC', $conn) or die ('Error: '.mysql_error()); function h($s) { echo htmlspecialchars($s, ENT_QUOTES); } function highlightWords($string, $word) { $string = preg_replace("/".preg_quote($word, "/")."/i", "<span class='highlight'>$0</span>", $string); /*** return the highlighted string ***/ return $string; } ?> <div class="caption">Search Results</div> <div class="center_div"> <table> <?php while ($row= mysql_fetch_array($result, MYSQL_ASSOC)) { $cQuote = highlightWords(htmlspecialchars($row['cQuotes']), $search_result); ?> <tr> <td style="text-align:right; font-size:18px;"><?php h($row['cArabic']); ?></td> <td style="font-size:16px;"><?php echo $cQuote; ?></td> <td style="font-size:12px;"><?php h($row['vAuthor']); ?></td> <td style="font-size:12px; font-style:italic; text-align:right;"><?php h($row['vReference']); ?></td> </tr> <?php } ?> </table> </div> search.html: <form name="myform" class="wrapper"> <input type="text" name="q" onkeyup="showUser()" class="txt_search"/> <input type="button" name="button" onclick="showUser()" class="button"/> <p> <div id="txtHint"></div> </form>

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• Write a program for a report derived from the data in the data file JEWELRY. The data is to be input

  - by Taylor

  here is the JEWELRY file 0011 Money_Clip 2.000 50.00 Other 0035 Paperweight 1.625 175.00 Other 0457 Cuff_Bracelet 2.375 150.00 Bracelet 0465 Links_Bracelet 7.125 425.00 Bracelet 0585 Key_Chain 1.325 50.00 Other 0595 Cuff_Links 0.625 525.00 Other 0935 Royale_Pendant 0.625 975.00 Pendant 1092 Bordeaux_Cross 1.625 425.00 Cross 1105 Victory_Medallion 0.875 30.00 Pendant 1111 Marquis_Cross 1.375 70.00 Cross 1160 Christina_Ring 0.500 175.00 Ring 1511 French_Clips 0.687 375.00 Other 1717 Pebble_Pendant 1.250 45.00 Pendant 1725 Folded_Pendant 1.250 45.00 Pendant 1730 Curio_Pendant 1.063 275.00 Pendant this is the program i have used #include <iostream> #include <string> #include <iomanip> #include <fstream> using namespace std; struct productJewelry { string name; double amount; int itemCode; double size; string group; }; int main() { // declare variables ifstream inFile; int count=0; int x=0; productJewelry product[50]; inFile.open("jewelry.txt"); // file must be in same folder if (inFile.fail()) cout << "failed"; cout << fixed << showpoint; // fixed format, two decimal places cout << setprecision(2); while (inFile.peek() != EOF) { // cout << count << " : "; count++; inFile>> product[x].itemCode; inFile>> product[x].name; inFile>> product[x].size; inFile>> product[x].amount; inFile>> product[x].group; // cout << product[x].itemCode << ", " << product[x].name << ", "<< product[x].size << ", " << product[x].amount << endl; x++; if (inFile.peek() == '\n') inFile.ignore(1, '\n'); } inFile.close(); string temp; bool swap; do { swap = false; for (int x=0; x<count;x++) { if (product[x].name>product[x+1].name) { //these 3 lines are to swap elements in array temp=product[x].name; product[x].name=product[x+1].name; product[x+1].name=temp; swap=true; } } } while (swap); for (x=0; x< count; x++) { //cout<< product[x].itemCode<<" "; //cout<< product[x].name <<" "; //cout<< product[x].size <<" "; //cout<< product[x].amount<<" "; //cout<< product[x].group<<" "<<endl; } system("pause"); // to freeze Dev-c++ output screen return 0; } // end main

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• FineUploader multiple instances and dynamic naming

  - by RichieMN

  I am using FineUploader 4.0.8 within a MVC4 project using the jquery wrapper. Here is an example of my js code that creates a single instance of the fineUploader and is working just fine. At this time, I have the need for more than one instance of fineUploader, but each individual control doesn't know anything about the other and they're rendered as needed on a page (I've seen previous questions using a jQuery .each, which won't work here). Currently, I can't seem to correctly render any upload buttons, probably due to having an ID duplicated or something. See below for how I'm using MVC's Razor to create unique variables and html IDs for that individual instance. Here's my current implementation where I've added the dynamic values (places where you see _@Model.{PropertyName}): // Uploader control setup var [email protected] = $('#[email protected]').fineUploader({ debug: true, template: '[email protected]', button: $("#[email protected]"), request: { endpoint: '@Url.Action("UploadFile", "Survey")', customHeaders: { Accept: 'application/json' }, params: { [email protected]: (function () { return instance; }), [email protected]: (function () { return surveyItemResultId; }), [email protected]: (function () { return itemId; }), [email protected]: (function () { return loopingCounter++; }) } }, validation: { acceptFiles: ['image/*', 'application/xls', 'application/pdf', 'text/csv', 'application/vnd.openxmlformats-officedocument.spreadsheetml.template', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', 'application/vnd.ms-excel'], allowedExtensions: ['jpeg', 'jpg', 'gif', 'png', 'bmp', 'csv', 'xls', 'xlsx', 'pdf', 'xlt', 'xltx', 'txt'], sizeLimit: 1024 * 1024 * 2.5, // 2.5MB stopOnFirstInvalidFile: false }, failedUploadTextDisplay: { mode: 'custom' }, multiple: true, text: { uploadButton: 'Select your upload file(s)' } }).on('submitted', function (event, id, filename) { $("#modal-overlay").fadeIn(); $("#modal-box").fadeIn(); [email protected]++; $(':input[type=button], :input[type=submit], :input[type=reset]').attr('disabled', 'disabled'); }).on('complete', function (event, id, filename, responseJSON) { [email protected]++; if ([email protected] == [email protected]) { $(':input[type=button], :input[type=submit], :input[type=reset]').removeAttr('disabled'); //$("#overlay").fadeOut(); $("#modal-box").fadeOut(); $("#modal-overlay").fadeOut(); } }).on('error', function (event, id, name, errorReason, xhr) { //$("#overlay").fadeOut(); alert('error: ' + errorReason); $("#modal-box").fadeOut(); $("#modal-overlay").fadeOut(); }); }); Using the same principle as above, I've added this logic to the template too. Here's part of my template: <script type="text/template" id="[email protected]"> <div class="qq-uploader-selector qq-uploader"> <div class="qq-upload-drop-area-selector qq-upload-drop-area qq-hide-dropzone"> <span>Drop files here to upload</span> What I see when I use the above code is only the drag and drop section visible, and no button. There are no js errors either. I do have an example that only has one instance of this control on it and the results are the same visible drag and drop section and no button). Any thought as to what's going on? I'll gladly update the question if you find I'm missing something helpful. Please don't just -1 me if it's something I can easily improve or fix.

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• To copy data from a webpage into an array of structs and sorted by“name” before producing the data.

  - by Taylor

  include include include include using namespace std; struct productJewelry { string name; double amount; int itemCode; double size; string group; }; int main() { // declare variables ifstream inFile; int count=0; int x=0; productJewelry product[50]; inFile.open("jewelry.txt"); // file must be in same folder if (inFile.fail()) cout << "failed"; cout << fixed << showpoint; // fixed format, two decimal places cout << setprecision(2); while (inFile.peek() != EOF) { // cout << count << " : "; count++; inFile product[x].itemCode; inFile product[x].name; inFile product[x].size; inFile product[x].amount; inFile product[x].group; // cout << product[x].itemCode << ", " << product[x].name << ", "<< product[x].size << ", " << product[x].amount << endl; x++; if (inFile.peek() == '\n') inFile.ignore(1, '\n'); } inFile.close(); string temp; bool swap; do { swap = false; for (int x=0; xproduct[x+1].name) { //these 3 lines are to swap elements in array temp=product[x].name; product[x].name=product[x+1].name; product[x+1].name=temp; swap=true; } } } while (swap); for (x=0; x< count; x++) { //cout<< product[x].itemCode<<" "; //cout<< product[x].name <<" "; //cout<< product[x].size <<" "; //cout<< product[x].amount<<" "; //cout<< product[x].group<<" "<<endl; } system("pause"); // to freeze Dev-c++ output screen return 0; } // end main THE FILE THAT NEEDS TO PRINT AND BE SORTED IN ALPHABETICAL ORDER 0011 Money_Clip 2.000 50.00 Other 0035 Paperweight 1.625 175.00 Other 0457 Cuff_Bracelet 2.375 150.00 Bracelet 0465 Links_Bracelet 7.125 425.00 Bracelet 0585 Key_Chain 1.325 50.00 Other 0595 Cuff_Links 0.625 525.00 Other 0935 Royale_Pendant 0.625 975.00 Pendant 1092 Bordeaux_Cross 1.625 425.00 Cross 1105 Victory_Medallion 0.875 30.00 Pendant 1111 Marquis_Cross 1.375 70.00 Cross 1160 Christina_Ring 0.500 175.00 Ring 1511 French_Clips 0.687 375.00 Other 1717 Pebble_Pendant 1.250 45.00 Pendant 1725 Folded_Pendant 1.250 45.00 Pendant 1730 Curio_Pendant 1.063 275.00 Pendant

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• To copy data from a webpage into an array of structs and sorted by"name" before producing the data.

  - by Taylor

  include include include include using namespace std; struct productJewelry { string name; double amount; int itemCode; double size; string group; }; int main() { // declare variables ifstream inFile; int count=0; int x=0; productJewelry product[50]; inFile.open("jewelry.txt"); // file must be in same folder if (inFile.fail()) cout << "failed"; cout << fixed << showpoint; // fixed format, two decimal places cout << setprecision(2); while (inFile.peek() != EOF) { // cout << count << " : "; count++; inFile product[x].itemCode; inFile product[x].name; inFile product[x].size; inFile product[x].amount; inFile product[x].group; // cout << product[x].itemCode << ", " << product[x].name << ", "<< product[x].size << ", " << product[x].amount << endl; x++; if (inFile.peek() == '\n') inFile.ignore(1, '\n'); } inFile.close(); string temp; bool swap; do { swap = false; for (int x=0; xproduct[x+1].name) { //these 3 lines are to swap elements in array temp=product[x].name; product[x].name=product[x+1].name; product[x+1].name=temp; swap=true; } } } while (swap); for (x=0; x< count; x++) { //cout<< product[x].itemCode<<" "; //cout<< product[x].name <<" "; //cout<< product[x].size <<" "; //cout<< product[x].amount<<" "; //cout<< product[x].group<<" "<<endl; } system("pause"); // to freeze Dev-c++ output screen return 0; } // end main

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• July 2013 Release of the Ajax Control Toolkit

  - by Stephen.Walther

  I’m super excited to announce the July 2013 release of the Ajax Control Toolkit. You can download the new version of the Ajax Control Toolkit from CodePlex (http://ajaxControlToolkit.CodePlex.com) or install the Ajax Control Toolkit from NuGet: With this release, we have completely rewritten the way the Ajax Control Toolkit combines, minifies, gzips, and caches JavaScript files. The goal of this release was to improve the performance of the Ajax Control Toolkit and make it easier to create custom Ajax Control Toolkit controls. Improving Ajax Control Toolkit Performance Previous releases of the Ajax Control Toolkit optimized performance for a single page but not multiple pages. When you visited each page in an app, the Ajax Control Toolkit would combine all of the JavaScript files required by the controls in the page into a new JavaScript file. So, even if every page in your app used the exact same controls, visitors would need to download a new combined Ajax Control Toolkit JavaScript file for each page visited. Downloading new scripts for each page that you visit does not lead to good performance. In general, you want to make as few requests for JavaScript files as possible and take maximum advantage of caching. For most apps, you would get much better performance if you could specify all of the Ajax Control Toolkit controls that you need for your entire app and create a single JavaScript file which could be used across your entire app. What a great idea! Introducing Control Bundles With this release of the Ajax Control Toolkit, we introduce the concept of Control Bundles. You define a Control Bundle to indicate the set of Ajax Control Toolkit controls that you want to use in your app. You define Control Bundles in a file located in the root of your application named AjaxControlToolkit.config. For example, the following AjaxControlToolkit.config file defines two Control Bundles: <ajaxControlToolkit> <controlBundles> <controlBundle> <control name="CalendarExtender" /> <control name="ComboBox" /> </controlBundle> <controlBundle name="CalendarBundle"> <control name="CalendarExtender"></control> </controlBundle> </controlBundles> </ajaxControlToolkit> The first Control Bundle in the file above does not have a name. When a Control Bundle does not have a name then it becomes the default Control Bundle for your entire application. The default Control Bundle is used by the ToolkitScriptManager by default. For example, the default Control Bundle is used when you declare the ToolkitScriptManager like this:  <ajaxToolkit:ToolkitScriptManager runat=”server” /> The default Control Bundle defined in the file above includes all of the scripts required for the CalendarExtender and ComboBox controls. All of the scripts required for both of these controls are combined, minified, gzipped, and cached automatically. The AjaxControlToolkit.config file above also defines a second Control Bundle with the name CalendarBundle. Here’s how you would use the CalendarBundle with the ToolkitScriptManager: <ajaxToolkit:ToolkitScriptManager runat="server"> <ControlBundles> <ajaxToolkit:ControlBundle Name="CalendarBundle" /> </ControlBundles> </ajaxToolkit:ToolkitScriptManager> In this case, only the JavaScript files required by the CalendarExtender control, and not the ComboBox, would be downloaded because the CalendarBundle lists only the CalendarExtender control. You can use multiple named control bundles with the ToolkitScriptManager and you will get all of the scripts from both bundles. Support for ControlBundles is a new feature of the ToolkitScriptManager that we introduced with this release. We extended the ToolkitScriptManager to support the Control Bundles that you can define in the AjaxControlToolkit.config file. Let me be explicit about the rules for Control Bundles: 1. If you do not create an AjaxControlToolkit.config file then the ToolkitScriptManager will download all of the JavaScript files required for all of the controls in the Ajax Control Toolkit. This is the easy but low performance option. 2. If you create an AjaxControlToolkit.config file and create a ControlBundle without a name then the ToolkitScriptManager uses that Control Bundle by default. For example, if you plan to use only the CalendarExtender and ComboBox controls in your application then you should create a default bundle that lists only these two controls. 3. If you create an AjaxControlToolkit.config file and create one or more named Control Bundles then you can use these named Control Bundles with the ToolkitScriptManager. For example, you might want to use different subsets of the Ajax Control Toolkit controls in different sections of your app. I should also mention that you can use the AjaxControlToolkit.config file with custom Ajax Control Toolkit controls – new controls that you write. For example, here is how you would register a set of custom controls from an assembly named MyAssembly: <ajaxControlToolkit> <controlBundles> <controlBundle name="CustomBundle"> <control name="MyAssembly.MyControl1" assembly="MyAssembly" /> <control name="MyAssembly.MyControl2" assembly="MyAssembly" /> </controlBundle> </ajaxControlToolkit> What about ASP.NET Bundling and Minification? The idea of Control Bundles is similar to the idea of Script Bundles used in ASP.NET Bundling and Minification. You might be wondering why we didn’t simply use Script Bundles with the Ajax Control Toolkit. There were several reasons. First, ASP.NET Bundling does not work with scripts embedded in an assembly. Because all of the scripts used by the Ajax Control Toolkit are embedded in the AjaxControlToolkit.dll assembly, ASP.NET Bundling was not an option. Second, Web Forms developers typically think at the level of controls and not at the level of individual scripts. We believe that it makes more sense for a Web Forms developer to specify the controls that they need in an app (CalendarExtender, ToggleButton) instead of the individual scripts that they need in an app (the 15 or so scripts required by the CalenderExtender). Finally, ASP.NET Bundling does not work with older versions of ASP.NET. The Ajax Control Toolkit needs to support ASP.NET 3.5, ASP.NET 4.0, and ASP.NET 4.5. Therefore, using ASP.NET Bundling was not an option. There is nothing wrong with using Control Bundles and Script Bundles side-by-side. The ASP.NET 4.0 and 4.5 ToolkitScriptManager supports both approaches to bundling scripts. Using the AjaxControlToolkit.CombineScriptsHandler Browsers cache JavaScript files by URL. For example, if you request the exact same JavaScript file from two different URLs then the exact same JavaScript file must be downloaded twice. However, if you request the same JavaScript file from the same URL more than once then it only needs to be downloaded once. With this release of the Ajax Control Toolkit, we have introduced a new HTTP Handler named the AjaxControlToolkit.CombineScriptsHandler. If you register this handler in your web.config file then the Ajax Control Toolkit can cache your JavaScript files for up to one year in the future automatically. You should register the handler in two places in your web.config file: in the <httpHandlers> section and the <system.webServer> section (don’t forget to register the handler for the AjaxFileUpload while you are there!). <httpHandlers> <add verb="*" path="AjaxFileUploadHandler.axd" type="AjaxControlToolkit.AjaxFileUploadHandler, AjaxControlToolkit" /> <add verb="*" path="CombineScriptsHandler.axd" type="AjaxControlToolkit.CombineScriptsHandler, AjaxControlToolkit" /> </httpHandlers> <system.webServer> <validation validateIntegratedModeConfiguration="false" /> <handlers> <add name="AjaxFileUploadHandler" verb="*" path="AjaxFileUploadHandler.axd" type="AjaxControlToolkit.AjaxFileUploadHandler, AjaxControlToolkit" /> <add name="CombineScriptsHandler" verb="*" path="CombineScriptsHandler.axd" type="AjaxControlToolkit.CombineScriptsHandler, AjaxControlToolkit" /> </handlers> <system.webServer> The handler is only used in release mode and not in debug mode. You can enable release mode in your web.config file like this: <compilation debug=”false”> You also can override the web.config setting with the ToolkitScriptManager like this: <act:ToolkitScriptManager ScriptMode=”Release” runat=”server”/> In release mode, scripts are combined, minified, gzipped, and cached with a far future cache header automatically. When the handler is not registered, scripts are requested from the page that contains the ToolkitScriptManager: When the handler is registered in the web.config file, scripts are requested from the handler: If you want the best performance, always register the handler. That way, the Ajax Control Toolkit can cache the bundled scripts across page requests with a far future cache header. If you don’t register the handler then a new JavaScript file must be downloaded whenever you travel to a new page. Dynamic Bundling and Minification Previous releases of the Ajax Control Toolkit used a Visual Studio build task to minify the JavaScript files used by the Ajax Control Toolkit controls. The disadvantage of this approach to minification is that it made it difficult to create custom Ajax Control Toolkit controls. Starting with this release of the Ajax Control Toolkit, we support dynamic minification. The JavaScript files in the Ajax Control Toolkit are minified at runtime instead of at build time. Scripts are minified only when in release mode. You can specify release mode with the web.config file or with the ToolkitScriptManager ScriptMode property. Because of this change, the Ajax Control Toolkit now depends on the Ajax Minifier. You must include a reference to AjaxMin.dll in your Visual Studio project or you cannot take advantage of runtime minification. If you install the Ajax Control Toolkit from NuGet then AjaxMin.dll is added to your project as a NuGet dependency automatically. If you download the Ajax Control Toolkit from CodePlex then the AjaxMin.dll is included in the download. This change means that you no longer need to do anything special to create a custom Ajax Control Toolkit. As an open source project, we hope more people will contribute to the Ajax Control Toolkit (Yes, I am looking at you.) We have been working hard on making it much easier to create new custom controls. More on this subject with the next release of the Ajax Control Toolkit. A Single Visual Studio Solution We also made substantial changes to the Visual Studio solution and projects used by the Ajax Control Toolkit with this release. This change will matter to you only if you need to work directly with the Ajax Control Toolkit source code. In previous releases of the Ajax Control Toolkit, we maintained separate solution and project files for ASP.NET 3.5, ASP.NET 4.0, and ASP.NET 4.5. Starting with this release, we now support a single Visual Studio 2012 solution that takes advantage of multi-targeting to build ASP.NET 3.5, ASP.NET 4.0, and ASP.NET 4.5 versions of the toolkit. This change means that you need Visual Studio 2012 to open the Ajax Control Toolkit project downloaded from CodePlex. For details on how we setup multi-targeting, please see Budi Adiono’s blog post: http://www.budiadiono.com/2013/07/25/visual-studio-2012-multi-targeting-framework-project/ Summary You can take advantage of this release of the Ajax Control Toolkit to significantly improve the performance of your website. You need to do two things: 1) You need to create an AjaxControlToolkit.config file which lists the controls used in your app and 2) You need to register the AjaxControlToolkit.CombineScriptsHandler in the web.config file. We made substantial changes to the Ajax Control Toolkit with this release. We think these changes will result in much better performance for multipage apps and make the process of building custom controls much easier. As always, we look forward to hearing your feedback.

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• Issue 15: Oracle PartnerNetwork Exchange @ Oracle OpenWorld

  - by rituchhibber

       ORACLE FOCUS Oracle PartnerNetwork Exchange@ ORACLE OpenWorld Sylvie MichouSenior DirectorPartner Marketing & Communications and Strategic Programs RESOURCES -- Oracle OpenWorld 2012 Oracle PartnerNetwork Exchange @ OpenWorld Oracle PartnerNetwork Exchange @ OpenWorld Registration Oracle PartnerNetwork Exchange SpecializationTest Fest Oracle OpenWorld Schedule Builder Oracle OpenWorld Promotional Toolkit for Partners Oracle Partner Events Oracle Partner Webcasts Oracle EMEA Partner News SUBSCRIBE FEEDBACK PREVIOUS ISSUES If you are attending our forthcoming Oracle OpenWorld 2012 conference in San Francisco from 30 September to 4 October, you will discover a new dedicated programme of keynotes and sessions tailored especially for you, our valued partners. Oracle PartnerNetwork Exchange @ OpenWorld has been created to enhance the opportunities for you to learn from and network with Oracle executives and experts. The programme also provides more informal opportunities than ever throughout the week to meet up with the people who are most important to your business: customers, prospects, colleagues and the Oracle EMEA Alliances & Channels management team. Oracle remains fully focused on building the industry's most admired partner ecosystem—which today spans over 25,000 partners. This new OPN Exchange programme offers an exciting change of pace for partners throughout the conference. Now it will be possible to enjoy a fully-integrated, partner-dedicated session schedule throughout the week, as well as key social events such as the Sunday night Welcome Reception, networking lunches from Monday to Thursday at the Howard Street Tent, and a fantastic closing event on the last Thursday afternoon. In addition to the regular Oracle OpenWorld conference schedule, if you have registered for the Oracle PartnerNetwork Exchange @ OpenWorld programme, you will be invited to attend a much anticipated global partner keynote presentation, plus more than 40 conference sessions aimed squarely at what's most important to you, as partners. Prominent topics for discussion will include: Oracle technologies and roadmaps and how they fit with partners' business plans; business development; regional distinctions in business practices; and much more. Each session will provide plenty of food for thought ahead of the numerous networking opportunities throughout the week, encouraging the knowledge exchange with Oracle executives, customers, prospects, and colleagues that will make this conference of even greater value for you. At Oracle we always work closely with our partners to deliver solution offerings that improve business value, simplify the IT experience and drive innovation and efficiencies for joint customers. The most important element of our new OPN Exchange is content that helps you get more from technology investments, more from your peer-to-peer connections, and more from your interactions with customers. To this end we've created some partner-specific tools which can be used by OPN members ahead of the conference itself. Crucially, a comprehensive Content Catalog already lists and organises details of every OPN Exchange session, speaker, exhibitor, demonstration and related materials. This Content Catalog can be used by all our partners to identify interesting content that you can add to your own personalised Oracle OpenWorld Schedule Builder, allowing more effective planning and pre-enrolment for vital sessions. There are numerous highlights that you will definitely want to include in those personal schedules. On Sunday morning, 30 September we will start the week with partner dedicated OPN Exchange sessions, following our Global Partner Keynote at 13:00 with Judson Althoff, SVP, Worldwide Alliances & Channels and Embedded Sales and senior executives, giving insight into Oracle's partner vision, strategy, and resources—all designed to help build and strengthen market opportunities for you. This will be followed by a number of OPN Exchange general sessions, the Oracle OpenWorld Opening Keynote with Larry Ellison, CEO, Oracle and concluded with the OPN Exchange AfterDark Welcome Reception, starting at 19:30 at the Metreon. From Monday 1 to Thursday 4 October, you can attend the OPN Exchange sessions that are most relevant to your business today and over the coming year. Oracle's top product and sales leaders will be on hand to discuss Oracle's strategic direction in 40+ targeted and in-depth sessions focussing on critical success factors to develop your business. Oracle's dedication to innovation, specialization, enablement and engineering provides Oracle partners with a huge opportunity to create new services and solutions, differentiate themselves and deliver extreme value to joint customers across the globe. Oracle will even be helping over 1000 partners to earn OPN Specialization certification during the Oracle OpenWorld OPN Exchange Test Fest, which will be providing all the study materials and exams required to drive Specialization for free at the conference. You simply need to check the list of current certification tracks available, and make sure you pre-register to reserve a seat in one of the ten sessions being offered free to OPN Exchange registered attendees. And finally, let's not forget those all-important networking opportunities, which can so often provide partners with valuable long-term alliances as well as exciting new business leads. The Oracle PartnerNetwork Lounge, located at Moscone South, exhibition hall, room 100 is the place where partners can meet formally or informally with colleagues, customers, prospects, and other industry professionals. OPN Specialized partners with OPN Exchange passes can also visit the OPN Video Blogging room to record and share ideas, and at the OPN Information Station you will find consultants available to answer your questions. "For the first time ever we will have a full partner conference within OpenWorld. OPN Exchange @ OpenWorld will kick-off on the first Sunday and run the entire week. We'll have over 40 sessions throughout that time and partners will hear from our top development executives, with special sessions dedicated to partnering throughout. It's going to be a phenomenal event, and we look forward to seeing our partners there." Judson Althoff, SVP, Oracle Worldwide Alliances & Channels and Embedded Sales So if you haven't done so already, please register for Oracle PartnerNetwork Exchange @ OpenWorld today or add OPN Exchange to your existing registration for just $100 through My Account. And if you have any further questions regarding partner activities at Oracle OpenWorld, please don't hesitate to contact the Oracle PartnerNetwork team at [email protected] will be on hand to share the very latest information about: Oracle's SPARC Superclusters: the latest Engineered Systems from Oracle, delivering radically improved performance, faster deployment and greatly reduced operational costs for mixed database and enterprise application consolidation Oracle's SPARC T4 servers: with the newly developed T4 processor and Oracle Solaris providing up to five times the single threaded performance and better overall system throughput for expanded application versatility Oracle Database Appliance: a new way to take advantage of the world's most popular database, Oracle Database 11g, in a single, easy-to-deploy and manage system. It's a complete package engineered to deliver simple, reliable and affordable database services to small and medium size businesses and departmental systems. All hardware and software components are supported together and offer customers unique pay-as-you-grow software licensing to quickly scale from two to 24 processor cores without incurring the costs and downtime usually associated with hardware upgrades Oracle Exalogic: the world's only integrated cloud machine, featuring server hardware and middleware software engineered together for maximum performance with minimum set-up and operational cost Oracle Exadata Database Machine: the only database machine that provides extreme performance for both data warehousing and online transaction processing (OLTP) applications, making it the ideal platform for consolidating onto grids or private clouds. It is a complete package of servers, storage, networking and software that is massively scalable, secure and redundant Oracle Sun ZFS Storage Appliances: providing enterprise-class NAS performance, price-performance, manageability and TCO by combining third-generation software with high-performance controllers, flash-based caches and disks Oracle Pillar Axiom Quality-of-Service: confidently consolidate storage for multiple applications into a single datacentre storage solution Oracle Solaris 11: delivering secure enterprise cloud deployments with the ability to run hundreds of virtual application with no overhead and co-engineered with other Oracle software products to provide the highest levels of security, manageability and performance Oracle Enterprise Manager 12c: Oracle's integrated enterprise IT management product, providing the industry's only complete, integrated and business-driven enterprise cloud management solution Oracle VM 3.0: the latest release of Oracle's server virtualisation and management solution, helping to move datacentres beyond server consolidation to improve application deployment and management. Register today and ensure your place at the Extreme Performance Tour! Extreme Performance Tour events are free to attend, but places are limited. To make sure that you don't miss out, please visit Oracle's Extreme Performance Tour website, select the city that you'd be interest in attending an event in, and then click on the 'Register Now' button for that city to secure your interest. Each individual city page also contains more in-depth information about your local event, including logistics, agenda and maybe even a preview of VIP guest speakers. -- Oracle OpenWorld 2010 Whether you attended Oracle OpenWorld 2009 or not, don't forget to save the date now for Oracle OpenWorld 2010. The event will be held a little earlier next year, from 19th-23rd September, so please don't miss out. With thousands of sessions and hundreds of exhibits and demos already lined up, there's no better place to learn how to optimise your existing systems, get an inside line on upcoming technology breakthroughs, and meet with your partner peers, Oracle strategists and even the developers responsible for the products and services that help you get better results for your end customers. Register Now for Oracle OpenWorld 2010! Perhaps you are interested in learning more about Oracle OpenWorld 2010, but don't wish to register at this time? Great! Please just enter your contact information here and we will contact you at a later date. How to Exhibit at Oracle OpenWorld 2010 Sponsorship Opportunities at Oracle OpenWorld 2010 Advertising Opportunities at Oracle OpenWorld 2010 -- Back to the welcome page

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• Implementing a generic repository for WCF data services

  - by cibrax

  The repository implementation I am going to discuss here is not exactly what someone would call repository in terms of DDD, but it is an abstraction layer that becomes handy at the moment of unit testing the code around this repository. In other words, you can easily create a mock to replace the real repository implementation. The WCF Data Services update for .NET 3.5 introduced a nice feature to support two way data bindings, which is very helpful for developing WPF or Silverlight based application but also for implementing the repository I am going to talk about. As part of this feature, the WCF Data Services Client library introduced a new collection DataServiceCollection<T> that implements INotifyPropertyChanged to notify the data context (DataServiceContext) about any change in the association links. This means that it is not longer necessary to manually set or remove the links in the data context when an item is added or removed from a collection. Before having this new collection, you basically used the following code to add a new item to a collection. Order order = new Order {   Name = "Foo" }; OrderItem item = new OrderItem {   Name = "bar",   UnitPrice = 10,   Qty = 1 }; var context = new OrderContext(); context.AddToOrders(order); context.AddToOrderItems(item); context.SetLink(item, "Order", order); context.SaveChanges(); Now, thanks to this new collection, everything is much simpler and similar to what you have in other ORMs like Entity Framework or L2S. Order order = new Order {   Name = "Foo" }; OrderItem item = new OrderItem {   Name = "bar",   UnitPrice = 10,   Qty = 1 }; order.Items.Add(item); var context = new OrderContext(); context.AddToOrders(order); context.SaveChanges(); In order to use this new feature, you first need to enable V2 in the data service, and then use some specific arguments in the datasvcutil tool (You can find more information about this new feature and how to use it in this post). DataSvcUtil /uri:"http://localhost:3655/MyDataService.svc/" /out:Reference.cs /dataservicecollection /version:2.0 Once you use those two arguments, the generated proxy classes will use DataServiceCollection<T> rather than a simple ObjectCollection<T>, which was the default collection in V1. There are some aspects that you need to know to use this feature correctly. 1. All the entities retrieved directly from the data context with a query track the changes and report those to the data context automatically. 2. A entity created with “new” does not track any change in the properties or associations. In order to enable change tracking in this entity, you need to do the following trick. public Order CreateOrder() {   var collection = new DataServiceCollection<Order>(this.context);   var order = new Order();   collection.Add(order);   return order; } You basically need to create a collection, and add the entity to that collection with the “Add” method to enable change tracking on that entity. 3. If you need to attach an existing entity (For example, if you created the entity with the “new” operator rather than retrieving it from the data context with a query) to a data context for tracking changes, you can use the “Load” method in the DataServiceCollection. var order = new Order {   Id = 1 }; var collection = new DataServiceCollection<Order>(this.context); collection.Load(order); In this case, the order with Id = 1 must exist on the data source exposed by the Data service. Otherwise, you will get an error because the entity did not exist. These cool extensions methods discussed by Stuart Leeks in this post to replace all the magic strings in the “Expand” operation with Expression Trees represent another feature I am going to use to implement this generic repository. Thanks to these extension methods, you could replace the following query with magic strings by a piece of code that only uses expressions. Magic strings, var customers = dataContext.Customers .Expand("Orders")         .Expand("Orders/Items") Expressions, var customers = dataContext.Customers .Expand(c => c.Orders.SubExpand(o => o.Items)) That query basically returns all the customers with their orders and order items. Ok, now that we have the automatic change tracking support and the expression support for explicitly loading entity associations, we are ready to create the repository. The interface for this repository looks like this,public interface IRepository { T Create<T>() where T : new(); void Update<T>(T entity); void Delete<T>(T entity); IQueryable<T> RetrieveAll<T>(params Expression<Func<T, object>>[] eagerProperties); IQueryable<T> Retrieve<T>(Expression<Func<T, bool>> predicate, params Expression<Func<T, object>>[] eagerProperties); void Attach<T>(T entity); void SaveChanges(); } The Retrieve and RetrieveAll methods are used to execute queries against the data service context. While both methods receive an array of expressions to load associations explicitly, only the Retrieve method receives a predicate representing the “where” clause. The following code represents the final implementation of this repository.public class DataServiceRepository: IRepository { ResourceRepositoryContext context; public DataServiceRepository() : this (new DataServiceContext()) { } public DataServiceRepository(DataServiceContext context) { this.context = context; } private static string ResolveEntitySet(Type type) { var entitySetAttribute = (EntitySetAttribute)type.GetCustomAttributes(typeof(EntitySetAttribute), true).FirstOrDefault(); if (entitySetAttribute != null) return entitySetAttribute.EntitySet; return null; } public T Create<T>() where T : new() { var collection = new DataServiceCollection<T>(this.context); var entity = new T(); collection.Add(entity); return entity; } public void Update<T>(T entity) { this.context.UpdateObject(entity); } public void Delete<T>(T entity) { this.context.DeleteObject(entity); } public void Attach<T>(T entity) { var collection = new DataServiceCollection<T>(this.context); collection.Load(entity); } public IQueryable<T> Retrieve<T>(Expression<Func<T, bool>> predicate, params Expression<Func<T, object>>[] eagerProperties) { var entitySet = ResolveEntitySet(typeof(T)); var query = context.CreateQuery<T>(entitySet); foreach (var e in eagerProperties) { query = query.Expand(e); } return query.Where(predicate); } public IQueryable<T> RetrieveAll<T>(params Expression<Func<T, object>>[] eagerProperties) { var entitySet = ResolveEntitySet(typeof(T)); var query = context.CreateQuery<T>(entitySet); foreach (var e in eagerProperties) { query = query.Expand(e); } return query; } public void SaveChanges() { this.context.SaveChanges(SaveChangesOptions.Batch); } } For instance, you can use the following code to retrieve customers with First name equal to “John”, and all their orders in a single call. repository.Retrieve<Customer>(    c => c.FirstName == “John”, //Where    c => c.Orders.SubExpand(o => o.Items)); In case, you want to have some pre-defined queries that you are going to use across several places, you can put them in an specific class. public static class CustomerQueries {   public static Expression<Func<Customer, bool>> LastNameEqualsTo(string lastName)   {     return c => c.LastName == lastName;   } } And then, use it with the repository. repository.Retrieve<Customer>(    CustomerQueries.LastNameEqualsTo("foo"),    c => c.Orders.SubExpand(o => o.Items));

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• Back to Basics: When does a .NET Assembly Dependency get loaded

  - by Rick Strahl

  When we work on typical day to day applications, it's easy to forget some of the core features of the .NET framework. For me personally it's been a long time since I've learned about some of the underlying CLR system level services even though I rely on them on a daily basis. I often think only about high level application constructs and/or high level framework functionality, but the low level stuff is often just taken for granted. Over the last week at DevConnections I had all sorts of low level discussions with other developers about the inner workings of this or that technology (especially in light of my Low Level ASP.NET Architecture talk and the Razor Hosting talk). One topic that came up a couple of times and ended up a point of confusion even amongst some seasoned developers (including some folks from Microsoft <snicker>) is when assemblies actually load into a .NET process. There are a number of different ways that assemblies are loaded in .NET. When you create a typical project assemblies usually come from: The Assembly reference list of the top level 'executable' project The Assembly references of referenced projects Dynamically loaded at runtime via AppDomain/Reflection loading In addition .NET automatically loads mscorlib (most of the System namespace) the boot process that hosts the .NET runtime in EXE apps, or some other kind of runtime hosting environment (runtime hosting in servers like IIS, SQL Server or COM Interop). In hosting environments the runtime host may also pre-load a bunch of assemblies on its own (for example the ASP.NET host requires all sorts of assemblies just to run itself, before ever routing into your user specific code). Assembly Loading The most obvious source of loaded assemblies is the top level application's assembly reference list. You can add assembly references to a top level application and those assembly references are then available to the application. In a nutshell, referenced assemblies are not immediately loaded - they are loaded on the fly as needed. So regardless of whether you have an assembly reference in a top level project, or a dependent assembly assemblies typically load on an as needed basis, unless explicitly loaded by user code. The same is true of dependent assemblies. To check this out I ran a simple test: I have a utility assembly Westwind.Utilities which is a general purpose library that can work in any type of project. Due to a couple of small requirements for encoding and a logging piece that allows logging Web content (dependency on HttpContext.Current) this utility library has a dependency on System.Web. Now System.Web is a pretty large assembly and generally you'd want to avoid adding it to a non-Web project if it can be helped. So I created a Console Application that loads my utility library: You can see that the top level Console app a reference to Westwind.Utilities and System.Data (beyond the core .NET libs). The Westwind.Utilities project on the other hand has quite a few dependencies including System.Web. I then add a main program that accesses only a simple utillity method in the Westwind.Utilities library that doesn't require any of the classes that access System.Web: static void Main(string[] args) { Console.WriteLine(StringUtils.NewStringId()); Console.ReadLine(); } StringUtils.NewStringId() calls into Westwind.Utilities, but it doesn't rely on System.Web. Any guesses what the assembly list looks like when I stop the code on the ReadLine() command? I'll wait here while you think about it… … … So, when I stop on ReadLine() and then fire up Process Explorer and check the assembly list I get: We can see here that .NET has not actually loaded any of the dependencies of the Westwind.Utilities assembly. Also not loaded is the top level System.Data reference even though it's in the dependent assembly list of the top level project. Since this particular function I called only uses core System functionality (contained in mscorlib) there's in fact nothing else loaded beyond the main application and my Westwind.Utilities assembly that contains the method accessed. None of the dependencies of Westwind.Utilities loaded. If you were to open the assembly in a disassembler like Reflector or ILSpy, you would however see all the compiled in dependencies. The referenced assemblies are in the dependency list and they are loadable, but they are not immediately loaded by the application. In other words the C# compiler and .NET linker are smart enough to figure out the dependencies based on the code that actually is referenced from your application and any dependencies cascading down into the dependencies from your top level application into the referenced assemblies. In the example above the usage requirement is pretty obvious since I'm only calling a single static method and then exiting the app, but in more complex applications these dependency relationships become very complicated - however it's all taken care of by the compiler and linker figuring out what types and members are actually referenced and including only those assemblies that are in fact referenced in your code or required by any of your dependencies. The good news here is: That if you are referencing an assembly that has a dependency on something like System.Web in a few places that are not actually accessed by any of your code or any dependent assembly code that you are calling, that assembly is never loaded into memory! Some Hosting Environments pre-load Assemblies The load behavior can vary however. In Console and desktop applications we have full control over assembly loading so we see the core CLR behavior. However other environments like ASP.NET for example will preload referenced assemblies explicitly as part of the startup process - primarily to minimize load conflicts. Specifically ASP.NET pre-loads all assemblies referenced in the assembly list and the /bin folder. So in Web applications it definitely pays to minimize your top level assemblies if they are not used. Understanding when Assemblies Load To clarify and see it actually happen what I described in the first example , let's look at a couple of other scenarios. To see assemblies loading at runtime in real time lets create a utility function to print out loaded assemblies to the console: public static void PrintAssemblies() { var assemblies = AppDomain.CurrentDomain.GetAssemblies(); foreach (var assembly in assemblies) { Console.WriteLine(assembly.GetName()); } } Now let's look at the first scenario where I have class method that references internally uses System.Web. In the first scenario lets add a method to my main program like this: static void Main(string[] args) { Console.WriteLine(StringUtils.NewStringId()); Console.ReadLine(); PrintAssemblies(); } public static void WebLogEntry() { var entry = new WebLogEntry(); entry.UpdateFromRequest(); Console.WriteLine(entry.QueryString); } UpdateFromWebRequest() internally accesses HttpContext.Current to read some information of the ASP.NET Request object so it clearly needs a reference System.Web to work. In this first example, the method that holds the calling code is never called, but exists as a static method that can potentially be called externally at some point. What do you think will happen here with the assembly loading? Will System.Web load in this example? No - it doesn't. Because the WebLogEntry() method is never called by the mainline application (or anywhere else) System.Web is not loaded. .NET dynamically loads assemblies as code that needs it is called. No code references the WebLogEntry() method and so System.Web is never loaded. Next, let's add the call to this method, which should trigger System.Web to be loaded because a dependency exists. Let's change the code to: static void Main(string[] args) { Console.WriteLine(StringUtils.NewStringId()); Console.WriteLine("--- Before:"); PrintAssemblies(); WebLogEntry(); Console.WriteLine("--- After:"); PrintAssemblies(); Console.ReadLine(); } public static void WebLogEntry() { var entry = new WebLogEntry(); entry.UpdateFromRequest(); Console.WriteLine(entry.QueryString); } Looking at the code now, when do you think System.Web will be loaded? Will the before list include it? Yup System.Web gets loaded, but only after it's actually referenced. In fact, just until before the call to UpdateFromRequest() System.Web is not loaded - it only loads when the method is actually called and requires the reference in the executing code. Moral of the Story So what have we learned - or maybe remembered again? Dependent Assembly References are not pre-loaded when an application starts (by default) Dependent Assemblies that are not referenced by executing code are never loaded Dependent Assemblies are just in time loaded when first referenced in code All of this is nothing new - .NET has always worked like this. But it's good to have a refresher now and then and go through the exercise of seeing it work in action. It's not one of those things we think about everyday, and as I found out last week, I couldn't remember exactly how it worked since it's been so long since I've learned about this. And apparently I'm not the only one as several other people I had discussions with in relation to loaded assemblies also didn't recall exactly what should happen or assumed incorrectly that just having a reference automatically loads the assembly. The moral of the story for me is: Trying at all costs to eliminate an assembly reference from a component is not quite as important as it's often made out to be. For example, the Westwind.Utilities module described above has a logging component, including a Web specific logging entry that supports pulling information from the active HTTP Context. Adding that feature requires a reference to System.Web. Should I worry about this in the scope of this library? Probably not, because if I don't use that one class of nearly a hundred, System.Web never gets pulled into the parent process. IOW, System.Web only loads when I use that specific feature and if I am, well I clearly have to be running in a Web environment anyway to use it realistically. The alternative would be considerably uglier: Pulling out the WebLogEntry class and sticking it into another assembly and breaking up the logging code. In this case - definitely not worth it. So, .NET definitely goes through some pretty nifty optimizations to ensure that it loads only what it needs and in most cases you can just rely on .NET to do the right thing. Sometimes though assembly loading can go wrong (especially when signed and versioned local assemblies are involved), but that's subject for a whole other post…© Rick Strahl, West Wind Technologies, 2005-2012Posted in .NET  CSharp   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• CodePlex Daily Summary for Saturday, June 05, 2010

  CodePlex Daily Summary for Saturday, June 05, 2010New Projects555 Calculator: A simple calculator to help choosing resistor and capacitor values to get the frequency you're looking for on a 555 timer.BleQua .NET: PL: Program sieciowy BleQua .NET jest multi-komunikatorem. EN: Network program BleQua .NET is multicomunicator.ChatDiplomaWork: ChatSample is the sample project.CSUFVGDC Summer Jam: Repository for VGDC summer game jam.Database Export Wizard: ExportWizard is a Step Wizard for Database Export using ASP.net and SQL Server. It allows easy export in any of the standard formats: CSV, TXT, HTM...Dozer Enterprise Library for .NET: a light .net framework for enterprise applications developmentEmployee Management System: This is an Employee Management System. the goal here is to offer a software that caters to small to mid sized businesses for free. This program a...Fanray: My project on Codeplex.Infragistics Analytics Framework: This project includes wrappers for the Infragistics controls that integrate with the recently launched Microsoft Silverlight Analytics Framework. ...KIME Simio Extensions: This is the official project of KIME Solutions. Here you find any current developments of KIME that are publicly available. KIME develops extension...MindTouch Community Extensions: MindTouch Community Extentions is a Native C# extention library for MindTouch Core that will have Dekiscript functions for full coverage of the API...NginxTray: NginxTray allows you manage easily Nginx Web Server by a Tray icon.NStore: NStore is a virtual store example done with ASP.NET MVC 2.0 tecnologyProjet Campus Numerique + Appli Mobile: Projet de création d'un campus numérique pour l'ISEN et d'un application mobile d'accès.SharePoint 2010 Feature Upgrade Kit: A set of tools for managing upgradable Features in SharePoint 2010. (Upgrading Features is a means of deploying code/artifact updates to existing S...SiteMap Utility for DNN Blog Module: This is a mini-project which allows you to easily add or generate an XML site map to your DotNetNuke® website for the search engines to use to inde...Space Explorer: A small app to help users examine folders to see which files and subfolders are taking up space. Still in development, no releases available curren...SQL Compact Toolbox: SQL Compact Toolbox is a Visual Studio 2010 add-in, that adds scripting, import, export, migrate, rename, run script and other upcoming SQL Server ...Twilverlight: Twliverlight is TweetDeck mixed with Silverlight. Much as I like using TweetDeck, it hogs my memory out, so this is an attempt to write a memory-ef...Visual Studio 2010 FxCop Extension: Visual Studio 2010 FxCop Extension allows to integrate stand-alone FxCop into Visual Studio 2010. You'll be able to analysis your source code with ...VisualStudio 2010 JavaScript Outlining: Visual Studio 2010 editor extension for JavaScript code blocks and custom regions outlining Wiki Shelf: Wiki Shelf is a Wikipedia browser app. The goal is to bring the library experience of browsing books, studying, and researching to the Wikipedia u...X-Arena - Magic: Projeto de PDS2 no Curso de Tecnologia em Desenvolvimento de Software no CEFETRN. O desenvolvimento do jogo Quiz Arena possui como pr...New Releases555 Calculator: 555Calc release v1.0: The initial 1 point uh-oh release of 555Calc.BleQua .NET: BleQua .NET 1.0.0.0: First releaseChatterbot JBot: JBot 1.0.1.155: Change presentation technology from Window Forms to Widndown Presentation Fundation.Community Forums NNTP bridge: Community Forums NNTP Bridge V26: Release of the Community Forums NNTP Bridge to access the social and anwsers MS forums with a single, open source NNTP bridge. This release has ad...Community Forums NNTP bridge: Community Forums NNTP Bridge V27: Release of the Community Forums NNTP Bridge to access the social and anwsers MS forums with a single, open source NNTP bridge. This release has ad...Community Forums NNTP bridge: Community Forums NNTP Bridge V28: Release of the Community Forums NNTP Bridge to access the social and anwsers MS forums with a single, open source NNTP bridge. This release has ad...CSS 360 Planetary Calendar: Final Release: =============================================================================== Final Release Version: 2.0 Tools Used: - Collaboration, Releas...Database Export Wizard: Version 3: As described in CodeProject article: Database Export Wizard for ASP.net and SQL Server. http://www.codeproject.com/KB/aspnet/DatabaseExportWizard.aspxEdu Math: Edu Math 2.0.10.122: Change version .NET Framework.Employee Management System: V1 (beta): This version is still in beta testing. Any issues, comments or suggestions are greatly appreciated. The export to excel function in this release o...ESB.NET: ESBDeploy_7.0.27.0 (x64 and x86) [ESB.NET 7.0 RC1]: Release Details Changes Since Last Release (since 6.3.47.1) - Targets .NET Framework 4, Visual Studio.NET 2010, Workflow 4 - Flowchart workflow ada...Free Silverlight & WPF Chart Control - Visifire: Visifire SL and WPF Charts v3.1.1 beta 2 Released: Hi, This release contains the following enhancements: *ShowIndicator() and HideIndicator() function has been implemented in Chart. So now user wi...Free Silverlight & WPF Chart Control - Visifire: Visifire SL and WPF Charts v3.5.4 beta 2 Released: Hi, This release contains the following enhancements: *ShowIndicator() and HideIndicator() function has been implemented in Chart. So now user wi...FsCheck: A random testing framework: FsCheck 0.7: What to download? If you use F# April 2010 CTP with Visual Studio 2008 or Visual Studio 2010, either Source or Binaries will do. To open source in...Git Source Control Provider: V 0.5: For VS 2010 users, it is recommanded to install it within Visual Studio by selecting Tools | Extension Manager. Run Visual Studio. Go to Tools ...GPdotNET - Genetic Programming Tool: GPdotNETv0.95: 1. Localization support 2. Export functionality for GP Model with training and testing data. 3. Export GPModel with Testing and Training data. 4....JoshDOS: JoshDOS 1.1: 1.1 adds a toutorial of how to create new commands and of course, you need the COMSOS user kit or dev kit. Ver 1.1 also includes a demo called Gue...KIME Simio Extensions: KIME.SimioDebugStep: This simple Simio step allows you to debug any number of expressions from within the simulation run. The debug information is displayed using a mes...NginxTray: NginxTray 0.3 Beta 2: NginxTray 0.3 Beta 2NginxTray: NginxTray 0.5 Beta 3: NginxTray 0.5 Beta 3NginxTray: NginxTray 0.6 RC1: NginxTray 0.6 RC1Open Source PLM Activities: Prodeos_OC beta 1.0: The “Innovator – MS Office Connector” is a product developed by Prodeos (www.prodeos.com). It is a light connector made to facilitate the use of Mi...Paint.NET PSD Plugin: 1.5.1: Changes in this release: Bitmap-mode images can now be loaded. Thanks to dhnc for filing the bug. Plugin no longer crashes on files with user m...SharePoint 2010 Feature Upgrade Kit: 1.0.0.0: This release contains:- - Custom application page to manage the upgrade of Site and Web-scoped Features. To come in the next release: - Companio...SiteMap Utility for DNN Blog Module: Blog SiteMap Utility v01.00.01: This is the first public release of the SiteMap Utility for the core DotNetNuke® Blog Module. Please see the documentation on this site on how to...SqlDiffFramework-A Visual Differencing Engine for Dissimilar Data Sources: SqlDiffFramework 1.0.2.0: Maintenance Release Defect Fixes: Issue # 3: 3 Issue # 4: 4 Enhancements: About Box now displays regional and language settings in effect. SDF...SuperSocket: First release of SuperSocket: !First release of SuperSocketThe Fastcopy Helper: FastcopyHelper: Fastcopy Helper 2.0 This is a final one. You can use it on the way. In order to use it , you should have the .NET3.5 ! 此软件必须下载 .NET3.5平台，方可使用！TV Show Renamer: TV Show Renamer Beta 3: I found the bug the prevented it from closing correctly so I fixed it and had to release it right away. If anyone else finds any problems. contact me.UrzaGatherer: UrzaGatherer v2.0: UrzaGatherer is the first stable version. This release include UrzaBackgroundPictures.VisualStudio 2010 JavaScript Outlining: VisualStudion 2010 Javascript Outlining 1.0: Features Outlines JavaScript codeblock regions for the code placed between { }. Both places on a new line. Outlines custom regions defined by: //...Wouter's SharePoint Demo Land: Navigation Service with Proxy: A SharePoint 2010 Service Application that uses service proxies to relay commands to the actual service. The demo proxy makes use of in-memory comm...盘古分词-开源中文分词组件: V2.0.0.0: 进一步优化性能，分词速度达到将近 500K ，1.2.0.1 版本只有 320K 修改 PanGu.Lucene.Analyzer, 支持 Lucene.net 2.9 版本。 增加对字典中以数字开头的专业非中文词汇的识别 增加英文分词开关，权重由英文小写权重和英文词根权重两个参数来决定...Most Popular ProjectsCommunity Forums NNTP bridgeOutSyncASP.NET MVC Time PlannerNeatUploadMoonyDesk (windows desktop widgets)AgUnit - Silverlight unit testing with ReSharperViperWorks IgnitionASP.NET MVC ExtensionsAviva Solutions C# Coding GuidelinesMute4Most Active ProjectsCommunity Forums NNTP bridgeRawrpatterns & practices – Enterprise LibraryIonics Isapi Rewrite FilterGMap.NET - Great Maps for Windows Forms & PresentationN2 CMSStyleCopFarseer Physics Enginesmark C# LibraryMirror Testing System

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• Issuing Current Time Increments in StreamInsight (A Practical Example)

  The issuing of a Current Time Increment, Cti, in StreamInsight is very definitely one of the most important concepts to learn if you want your Streams to be responsive. A full discussion of how to issue Ctis is beyond the scope of this article but a very good explanation in addition to Books Online can be found in these three articles by a member of the StreamInsight team at Microsoft, Ciprian Gerea. Time in StreamInsight Series http://blogs.msdn.com/b/streaminsight/archive/2010/07/23/time-in-streaminsight-i.aspx http://blogs.msdn.com/b/streaminsight/archive/2010/07/30/time-in-streaminsight-ii.aspx http://blogs.msdn.com/b/streaminsight/archive/2010/08/03/time-in-streaminsight-iii.aspx A lot of the problems I see with unresponsive or stuck streams on the MSDN Forums are to do with how Ctis are enqueued or in a lot of cases not enqueued. If you enqueue events and never enqueue a Cti then StreamInsight will be perfectly happy. You, on the other hand, will never see data on the output as you have not told StreamInsight to flush the stream. This article deals with a specific implementation problem I had recently whilst working on a StreamInsight project. I look at some possible options and discuss why they would not work before showing the way I solved the problem. The stream of data I was dealing with on this project was very bursty that is to say when events were flowing they came through very quickly and in large numbers (1000 events/sec), but when the stream calmed down it could be a few seconds between each event. When enqueuing events into the StreamInsight engne it is best practice to do so with a StartTime that is given to you by the system producing the event . StreamInsight processes events and it doesn't matter whether those events are being pushed into the engine by a source system or the events are being read from something like a flat file in a directory somewhere. You can apply the same logic and temporal algebra to both situations. Reading from a file is an excellent example of where the time of the event on the source itself is very important. We could be reading that file a long time after it was written. Being able to read the StartTime from the events allows us to define windows that will hold the correct sets of events. I was able to do this with my stream but this is where my problems started. Below is a very simple script to create a SQL Server table and populate it with sample data that will show exactly the problem I had. CREATE TABLE [dbo].[t] ( [c1] [int] PRIMARY KEY, [c2] [datetime] NULL ) INSERT t VALUES (1,'20100810'),(2,'20100810'),(3,'20100810') Column c2 defines the StartTime of the event on the source and as you can see the values in all 3 rows of data is the same. If we read Ciprian’s articles we know that we can define how Ctis get injected into the stream in 3 different places The Stream Definition The Input Factory The Input Adapter I personally have always been a fan of enqueing Ctis through the factory. Below is code typical of what I would use to do this On the class itself I do some inheriting public class SimpleInputFactory : ITypedInputAdapterFactory<SimpleInputConfig>, ITypedDeclareAdvanceTimeProperties<SimpleInputConfig> And then I implement the following function public AdapterAdvanceTimeSettings DeclareAdvanceTimeProperties<TPayload>(SimpleInputConfig configInfo, EventShape eventShape) { return new AdapterAdvanceTimeSettings( new AdvanceTimeGenerationSettings(configInfo.CtiFrequency, TimeSpan.FromTicks(-1)), AdvanceTimePolicy.Adjust); } The configInfo .CtiFrequency property is a value I pass through to define after how many events I want a Cti to be injected and this in turn will flush through the stream of data. I usually pass a value of 1 for this setting. The second parameter determines the CTI timestamp in terms of a delay relative to the events. -1 ticks in the past results in 1 tick in the future, i.e., ahead of the event. The problem with this method though is that if consecutive events have the same StartTime then only one of those events will be enqueued. In this example I use the following to define how I assign the StartTime of my events currEvent.StartTime = (DateTimeOffset)dt.c2; If I go ahead and run my StreamInsight process with this configuration i can see on the output adapter that two events have been removed To see this in a little more depth I can use the StreamInsight Debugger and see what happens internally. What is happening here is that the first event arrives and a Cti is injected with a time of 1 tick after the StartTime of that event (Also the EndTime of the event). The second event arrives and it has a StartTime of before the Cti and even though we specified AdvanceTimePolicy.Adjust on the factory we know that a point event can never be adjusted like this and the event is dropped. The same happens for the third event as well (The second and third events get trumped by the Cti). For a more detailed discussion of why this happens look here http://www.sqlis.com/sqlis/post/AdvanceTimePolicy-and-Point-Event-Streams-In-StreamInsight.aspx We end up with a single event being pushed into the output adapter and our result now makes sense. The next way I tried to solve this problem by changing the value of the second parameter to TimeSpan.Zero Here is how my factory code now looks public AdapterAdvanceTimeSettings DeclareAdvanceTimeProperties<TPayload>(SimpleInputConfig configInfo, EventShape eventShape) { return new AdapterAdvanceTimeSettings( new AdvanceTimeGenerationSettings(configInfo.CtiFrequency, TimeSpan.Zero), AdvanceTimePolicy.Adjust); } What I am doing here is declaring a policy that says inject a Cti together with every event and stamp it with a StartTime that is equal to the start time of the event itself (TimeSpan.Zero). This method has plus points as well as a downside. The upside is that no events will be lost by having the same StartTime as previous events. The Downside is that because the Cti is declared with the StartTime of the event itself then it does not actually flush that particular event because in the StreamInsight algebra, a Cti commits only those events that occurred strictly before them. To flush the events we need a Cti to be enqueued with a greater StartTime than the events themselves. Here is what happened when I ran this configuration As you can see all we got through was the Cti and none of the events. The debugger output shows the stamps on the Cti and the events themselves. Because the Cti issued has the same timestamp (StartTime) as the events then none of the events get flushed. I was nearly there but not quite. Because my stream was bursty it was possible that the next event would not come along for a few seconds and this was far too long for an event to be enqueued and not be flushed to the output adapter. I needed another solution. Two possible solutions crossed my mind although only one of them made sense when I explored it some more. Where multiple events have the same StartTime I could add 1 tick to the first event, two to the second, three to third etc thereby giving them unique StartTime values. Add a timer to manually inject Ctis The problem with the first implementation is that I would be giving the events a new StartTime. This would cause me the following problems If I want to define windows over the stream then some events may not be captured in the right windows and therefore any calculations on those windows I did would be wrong What would happen if we had 10,000 events with the same StartTime? I would enqueue them with StartTime + n ticks. Along comes a genuine event with a StartTime of the very first event + 1 tick. It is now too far in the past as far as my stream is concerned and it would be dropped. Not what I would want to do at all. I decided then to look at the Timer based solution I created a timer on my input adapter that elapsed every 200ms. private Timer tmr; public SimpleInputAdapter(SimpleInputConfig configInfo) { ctx = new SimpleTimeExtractDataContext(configInfo.ConnectionString); this.configInfo = configInfo; tmr = new Timer(200); tmr.Elapsed += new ElapsedEventHandler(t_Elapsed); tmr.Enabled = true; } void t_Elapsed(object sender, ElapsedEventArgs e) { ts = DateTime.Now - dtCtiIssued; if (ts.TotalMilliseconds >= 200 && TimerIssuedCti == false) { EnqueueCtiEvent(System.DateTime.Now.AddTicks(-100)); TimerIssuedCti = true; } }   In the t_Elapsed event handler I find out the difference in time between now and when the last event was processed (dtCtiIssued). I then check to see if that is greater than or equal to 200ms and if the last issuing of a Cti was done by the timer or by a genuine event (TimerIssuedCti). If I didn’t do this check then I would enqueue a Cti every time the timer elapsed which is not something I wanted. If the difference between the two times is greater than or equal to 500ms and the last event enqueued was by a real event then I issue a Cti through the timer to flush the event Queue, otherwise I do nothing. When I enqueue the Ctis into my stream in my ProduceEvents method I also set the values of dtCtiIssued and TimerIssuedCti   currEvent = CreateInsertEvent(); currEvent.StartTime = (DateTimeOffset)dt.c2; TimerIssuedCti = false; dtCtiIssued = currEvent.StartTime; If I go ahead and run this configuration I see the following in my output. As we can see the first Cti gets enqueued as before but then another is enqueued by the timer and because this has a later timestamp it flushes the enqueued events through the engine. Conclusion Hopefully this has shown how the enqueuing of Ctis can have a dramatic effect on the responsiveness of your output in StreamInsight. Understanding the temporal nature of the product is for me one of the most important things you can learn. I have attached my solution for the demos. It is all in one project and testing each variation is a simple matter of commenting and un-commenting the parts in the code we have been dealing with here.

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• NINE Questions with Michelle Juett

  - by NINEQuestions

  Michelle Juett is one of the more interesting people I know, even though we’ve never met face to face. She’s part artist, part techie and all cool. We “met” via my good buddy George Clingerman and have plotting to take over the world, errr… I mean “collaborating” ever since. If you happen to live in the Seattle area, you can catch her and her work at Sakura Con on April 2-4, 2010 and various other gamer and art cons throughout the year. You can also find her on Twitter as @Shelldragon. Now that you know a little bit, I’ll let her tell you the rest of the story in these NINE Questions: 1. Where are you from? I was born in Clearwater, Florida. I like to tell people I'm from the Bermuda Triangle, it just makes explaining myself so much easier. My family moved to Washington when I was 5 and I've been in the Pacific Northwest ever since. We like to QQ about the rain but we really love the green trees and clean water. 2. What do you do? I fight evil by moonlight and win love by daylight.. or something like that.  I’ve been in quality assurance for games during the day since January 2008 and an artist for life. I currently work in QA for a really awesome game company in Bellevue.  At home, I work on personal digital art, making game assets as well as other random freelance projects as they pop up. 3. How did you get to where you are now? I'm still not where I want to be but I'm getting closer. The biggest piece of advice I can give is to work hard and never settle for the minimum required. I tend to overwork myself but I've never regretted it. You can want something really bad but if you aren't willing to work for it, then you can't expect it to just happen. I've always drawn and had an unhealthy love for video games that I was told I’d grow out of.  I knew I would not ‘grow out’ of games and that real adults make them and I could too. After I graduated, in searching for jobs, I discovered game testing. I figured this would be a good way to get my foot in the door and start networking. I’ve worked with consoles, websites and now, PC games.  I stuck with my journey, although it has been a rocky one, daylighting as a tester and moonlighting as an artist. I'm still on that journey but I wouldn't have it any other way. Test has given me a perspective that is difficult, if not impossible, to obtain any other way. It gives an unconditional respect for other hard working testers and an insight into creative problem solving. 4. So video game testing probably sounds WAY cooler than the reality. What's it like? What's a given day for you? Game testers don't get a lot of respect because of their stigmas and the fact most people don't actually know what we do.  People hear about the opening and closing disc trays all day. Many places do treat their testers like numbers. It all depends on where you work and how awesome your company is. I've had to deal with a lot of bad work situations to get to a really good one. QA exists to ensure the game is as flawless and enjoyable as it can be by the time it has to leave the nest and go out into the world. This includes everything obvious: “can I beat the level and save the princess?” to the more obscure: ‘What happens when I lose internet connection while trying to save right before falling into a pit to my death while holding the jump key then my cat pulls out my memory card and hides it in her litter box?” On the dev side, for developers, testers can be very scary people. Especially when the test team is not in house and you can’t see each other’s faces.  I've seen both sides. We don't mean to hurt your feelings. We really DO love you and want your game to be the best it can be! It can be some serious tough love. 5. You are also an accomplished artist. Got any major projects right now you'd like to talk about? LOL, I don't know if I’d say I'm an accomplished artist just yet. I’m still a long way from where I want to be. I figure that’s what makes you grow though: the desire to never stop improving. I like QA but I want to be a full time artist. I was lucky enough to register for a table at Sakura Con in the 11 second window that the tables sold out. As such, I’ll be selling my wares in the Artist Alley April 2-4th. Part of preparing for this is actually making the art to be sold there. Anime is a fun pass time but I don’t draw a whole lot of it so I’m making up for lost time. As I seem to enjoy burying myself in work, I’m an art lead for a secret project that’s so secret I might be killed tonight for even mentioning it. I also take on various freelance projects and do what I can to help out indie games. I discovered the XNA community a year and a half ago and developed a love for Indies when I was writing a weekly newsletter on XBLA news. I’m a little late to the party but I find myself in a unique position where I am an artist and also have technical skills in games. While not programmer myself, I have a lot of game sense and experience. I hope to make some awesome happen. Lastly, I have an ongoing web comic Shell’s Angels) that tends to get neglected when I get busy. I still love drawing comics and keep a little book with me to sketch down ideas as they pop into my head. I may pick it back up again as a larger project sometime in the future. 6. Can you talk about any of the other freelance projects you're doing or are you sworn to secrecy on those too? We wouldn't want a team of game developer ninjas to take you out or anything. All my projects are currently 2d. I have personal projects such as the ongoing comic as well as a graphic novel I've been picking at here and there. My main focus until April is Sakura Con, Sakura Con, Sakura Con.  I see it as a great way to get exposure and convention experience. I found out I love conventions a couple years ago and I want to get more involved in them. 7. As an artist, what is your weapon of choice? What do you use to get most of your stuff done? I am a Photoshop Hero and I have the hoodie to prove it. (http://www.pennyarcademerch.com/pah090011.html) I've dabbled in other paint programs but I always gravitate back to Photoshop. She is my one true love. I'd like to learn programs like Flash or Anime Studio when I get a bit more time because of their animation abilities. I've worked on frame by frame animation forever but I would love to learn 2d rigging. Still, nothing can compare to a simple sketchpad and a pencil. I always have one on me in case I come across or think of something interesting and can't get to a computer. If the Courier ever comes to exist it will be an ideal weapon for me. 8. You did some videos too, depicting the art creation process. What was the motivation behind those? The creative process is just as important as the final product, if not more so.  I've always loved watching speed paint videos and wanted to try it out myself. Turns out it's a lot of work and time but it's definitely fun to go back and rewatch them. Art isn't always the end result and is more often the process itself. 9. Got any interesting tattoos? Designed any for yourself or other people? Not yet, but not for lack of desire. I've toiled over what and where for years. Last year, I finally decided the back of my shoulders would be the place. Like anything permanent, I want it to have meaning. I thought of somehow incorporating games but I couldn't find something I felt would stand the test of time even with all the classic sprite games. I'm very picky so we'll see if I can get something solid decided. Come see me at Sakura Con April 2 -4!!!

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• Part 2: Career development as a Software Developer without becoming a manager.

  - by albertpascual

  Seems like my previous post inspired by the work of Michael “Doc” Norton was a great success for the amount of emails I have received. Yet amazed how many people didn’t want to discuss their questions in the comments  sections. I would encourage people to be more public, still I would like to reply to all of you on this public media. I still welcome those emails. What I found out is that many people feels like me, they want to be developers and still be compensated for their experience without wanting to take a job as a manager. Their perfect day is a full day of coding and learning. Many believe their companies will never pay a manager’s salary to a developer no matter what. Most of you ask how to get the ball rolling. And is the later that I’m addressing here, the previous group, will never try. What companies understand developers value and where can I find them? This is a very difficult question to ask, I don’t have a list of those companies or departments, I have seen in my past signs in companies bending backwards to compensate, in more ways the monetary, a developer that is a good resource to them. Allowing the person to move out of the state and still let them work for the company from home is a sign that company goes by individual cases. Allowing them to go to conference that will not benefit the company is another big sign. Simple signs like flexible hours and letting some people work from home. To see those signs you need to be working in that company for awhile and look at the departments where the manager is taking care of their employees in individual cases. Look for the department where people get quiet extra perks, where some people in the department work from home or remotely. In my experience, but not always true, medium to big companies, are prompt to recognize good developers. Then again, some companies just don’t get it and is when you see many technical people managing developers. For all the people that email me stating that developers can also be very good managers, I do not disagree, I just think that a good developers loves writing code, when you remove that part the better salary isn’t enough to keep a developer happy. Burned out developers appreciate being promoted to managers. How do I know I work in a bad company? In my experience I have been a consultant and seen many companies, a few signs I have learned about companies that will not recognize good developers are: When the turn over is pretty high, when developers are moving out in a big rate, no rocket scientist needs to tap you in the shoulder. When the company is looking always to outsource their development resources. The product is not that interesting nor the company cares too much for their final result and support. Code sweat shops. You’ll know when you start working in one of those. Run for the hills! Where do I start? Disclaimer: I have only based this post on Michael “Doc” Norton, this is just my interpretation and ideas. First thing is to look at Michael “Doc” Norton presentation Take Control of Your Development Career http://docondev.blogspot.com/ That should be the first thing any developer should look and follow like it was a pattern. I would personally recommend to find some language or pattern you are interested with and learn it, learn something that will make you happy. Second, join a User Group and get involve in the community. There are hundreds of user groups, and I’m sure you’ll find one in your city or near you town. Code Camps are Developers Meet Ups are also good resources. Third, I would join a open source project you are interested or better yet, create a new open source project with the new technology that you have learn and get coding. Fourth, create a Twitter account and follow the people that talks about the technology you are interested on. If you follow this 4 steps above I think you’ll be on your way, after they are complete, when you release your Open Source project you can say that you accomplished the first steps. Now, do not expect anything to change in your career life, you are changing and should not expect anything in return, besides borrowing some time from sleeping and your family. Creating a good schedule may help you, I find wasted time in many places that I use. Flying for work is actually one of those that allows me to do my best work on a airplane, don’t need to borrow time from anywhere else. Making sure you always have a light, charged laptop is so important. Next steps following the Michael “Doc” Norton Pattern or my interpretation of. First, help run a user group or better yet, start a new user group. I’ll add, as well, go to one conference a year and free development events around your city; Code Camps, Geek Dinners, etc. There are many free events sponsored by different companies for developers to get to know their products, I highly recommend those as the way to get connected. Second, chose a mentor, this is a very hard thing to do I experienced, find an expert in the technology you are learning that has the time for you, it is difficult, I wish you best of luck. Third, learn another technology or pattern, open your horizons a little bit more. Why not, if you had fun previously, keep doing it. Fourth, get involved in forums to answer and ask questions, getting notice in public forums is rewarding for your ego after such a long journey. Final steps following the Michael “Doc” Norton Pattern Teach what you know, become humble on your knowledge, find as many opportunities to teach and to get involved with the community, bring all that to your day job. Mr. Norton talks about getting naked, expose yourself to others in your knowledge and what you do not know. You are never too important for small opportunities, yet don’t  be afraid to take anything big and learn from the experience. Anytime you have the opportunity to talk to somebody that has reach the point the community knows his or her name, means that you should learn from it. Take opportunities that won’t make you money, yet will make you happy. Sometimes you need to spend money and time. Register talks in Code Camps and Dev Meet Ups, those are free, also go to Conference, Development Summits and Geek Diners for example. One day, people will pay you to attend. When will all these pay off? I don’t know. I’m still in the path, there are a few things that during your journey you may get little acknowledgements that you are in the correct path. In my case I think those are the little signs that tells you about your journey. I got awarded the Microsoft Most Valuable Professional for ASP.NET in 2007, 2008, 2009 and 2010. I got selected to speak at the DevConnections in Las Vegas in 2010 and Orlando 2011. I do believe that I do have a long way to go, yet what I do makes me happy and I hope I can keep doing for years to come. Every year I can see an improvement on my code, and more frameworks and languages are under my belt, I learn to embrace them all as well as in my daily job, I have been able to work in a few projects beyond my department. I’m a learner and believer of the Michael “Doc” Norton pattern. Looking forward to learn more about it to be able to apply it better. In my short journey I now see my mistakes, I did a few things right, I have been listening the intelligent people and not being afraid to move along the technology changes. In my professional life, I have tried to avoid being placed in only one technology and product. I have always share my code and never confused anybody that wanted to take over any of my projects, I didn’t think anything I created as my own nor care too much when politics didn’t see my vision. I stayed flexible, ready and visible, yet humble. I keep my head just below the clouds, and avoided managers meetings. I credit my manager for my success, and I faulted publicly only myself for the failures. Hope this helps. Cheers, Al Follow me in Twitter  Read my previous post tweetmeme_url = 'http://weblogs.asp.net/albertpascual/archive/2010/12/09/part-2-career-development-as-a-software-developer-without-becoming-a-manager.aspx'; tweetmeme_source = 'alpascual';

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• Looking Back at MIX10

  - by WeigeltRo

  It’s the sad truth of my life that even though I’m fascinated by airplanes and flight in general since my childhood days, my body doesn’t like flying. Even the ridiculously short flights inside Germany are taking their toll on me each time. Now combine this with sitting in the cramped space of economy class for many hours on a transatlantic flight from Germany to Las Vegas and back, and factor in some heavy dose of jet lag (especially on my way eastwards), and you get an idea why after coming back home I had this question on my mind: Was it really worth it to attend MIX10? This of course is a question that will also be asked by my boss at Comma Soft (for other reasons, obviously), who decided to send me and my colleague Jens Schaller, to the MIX10 conference. (A note to my German readers: An dieser Stelle der Hinweis, dass Comma Soft noch Silverlight-Entwickler und/oder UI-Designer für den Standort Bonn sucht – aussagekräftige Bewerbungen bitte an [email protected]) Too keep things short: My answer is yes. Before I’ll go into detail, let me ask the heretical questions whether tech conferences in general still make sense. There was a time, where actually being at a tech conference gave you a head-start in regard to learning about new technologies. Nowadays this is no longer true, where every bit of information and every detail is immediately twittered, blogged and whatevered to death. In the case of MIX10 you even can download the video-taped sessions shortly after. So: Does visiting a conference still make sense? It depends on what you expect from a conference. It should be clear to everybody that you’ll neither get exclusive information, nor receive training in a small group. What a conference does offer that sitting in front of your computer does not can be summarized as follows: Focus Being away from work and home will help you to focus on the presented information. Of course there are always the poor guys who are haunted by their work (with mails and short text messages reporting the latest showstopper problem), but in general being out of your office makes a huge difference. Inspiration With the focus comes the emotional involvement. I find it much easier to absorb information if I feel that certain vibe when sitting in a session. This still means that I have put work into reviewing the information later, but it’s a better starting point. And all the impressions collected at a (good) conference combined lead to a higher motivation – be it by the buzz (“this is gonna be sooo cool!”) or by the fear to fall behind (“man, we’ll have work on this, or else…”). People At a conference it’s pretty easy to get into contact with other people during breakfast, lunch and other breaks. This is a good opportunity to get a feel for what other development teams are doing (on a very general level of course, nobody will tell you about their secret formula) and what they are thinking about specific technologies. So MIX10 did offer focus, inspiration and people, but that would have meant nothing without valuable content. When I (being a frontend developer with a strong interest in UI/UX) planned my visit to MIX10, I made the decision to focus on the "soft" topics of design, interaction and user experience. I figured that I would be bombarded with all the technical details about Silverlight 4 anyway in the weeks and months to come. Actually, I would have liked to catch a few technical sessions, but the agenda wasn’t exactly in favor of people interested in any kind of Silverlight and UI/UX/Design topics. That’s one of my few complaints about the conference – I would have liked one more day and/or more sessions per day. Overall, the quality of the workshops and sessions was pretty high. In fact, looking back at my collection of conferences I’ve visited in the past I’d say that MIX10 ranks somewhere near the top spot. Here’s an overview of the workshops/sessions I attended (I’ll leave out the keynotes): Day 0 (Workshops on Sunday) Design Fundamentals for Developers Robby Ingebretsen is the man! Great workshop in three parts with the perfect mix of examples, well-structured definition of terminology and the right dose of humor. Robby was part of the WPF team before founding his own company so he not only has a strong interest in design (and the skillz!) but also the technical background.   Design Tools and Techniques Originally announced to be held by Arturo Toledo, the Rosso brothers from ArcheType filled in for the first two parts, and Corrina Black had a pretty general part about the Windows Phone UI. The first two thirds were a mixed bag; the two guys definitely knew what they were talking about, and the demos were great, but the talk lacked the preparation and polish of a truly great presentation. Corrina was not allowed to go into too much detail before the keynote on Monday, but the session was still very interesting as it showed how much thought went into the Windows Phone UI (and there’s always a lot to learn when people talk about their thought process). Day 1 (Monday) Designing Rich Experiences for Data-Centric Applications I wonder whether there was ever a test-run for this session, but what Ken Azuma and Yoshihiro Saito delivered in the first 15 minutes of a 30-minutes-session made me walk out. A commercial for a product (just great: a video showing a SharePoint plug-in in an all-Japanese UI) combined with the most generic blah blah one could imagine. EPIC FAIL.   Great User Experiences: Seamlessly Blending Technology & Design I switched to this session from the one above but I guess I missed the interesting part – what I did catch was what looked like a “look at the cool stuff we did” without being helpful. Or maybe I was just in a bad mood after the other session.   The Art, Technology and Science of Reading This talk by Kevin Larson was very interesting, but was more a presentation of what Microsoft is doing in research (pretty impressive) and in the end lacked a bit the helpful advice one could have hoped for.   10 Ways to Attack a Design Problem and Come Out Winning Robby Ingebretsen again, and again a great mix of theory and practice. The clean and simple, yet effective, UI of the reader app resulted in a simultaneous “wow” of Jens and me. If you’d watch only one session video, this should be it. Microsoft has to bring Robby back next year! Day 2 (Tuesday) Touch in Public: Multi-touch Interaction Design for Kiosks & Architectural Experiences Very interesting session by Jason Brush, a great inspiration with many details to look out for in the examples. Exactly what I was hoping for – and then some!   Designing Bing: Heart and Science How hard can it be to design the UI for a search engine? An input field and a list of results, that should be it, right? Well, not so fast! The talk by Paul Ray showed the many iterations to finally get it right (up to the choice of a specific blue for the links). And yes, I want an eye-tracking device to play around with!   The Elephant in the Room When Nishant Kothary presented a long list of what his session was not about, I told to myself (not having the description text present) “Am I in the wrong talk? Should I leave?”. Boy, was I wrong. A great talk about human factors in the process of designing stuff.   An Hour with Bill Buxton Having seen Bill Buxton’s presentation in the keynote, I just had to see this man again – even though I didn’t know what to expect. Being more or less unplanned and intended to be more of a conversation, the session didn’t provide a wealth of immediately useful information. Nevertheless Bill Buxton was impressive with his huge knowledge of seemingly everything. But this could/should have been a session some when in the evening and not in parallel to at least two other interesting talks. Day 3 (Wednesday) Design the Ordinary, Like the Fixie This session by DL Byron and Kevin Tamura started really well and brought across the message to keep things simple. But towards the end the talk lost some of its steam. And, as a member of the audience pointed out, they kind of ignored their own advice when they used a fancy presentation software other then PowerPoint that sometimes got in the way of showing things.   Developing Natural User Interfaces Speaking of alternative presentation software, Joshua Blake definitely had the most remarkable alternative to PowerPoint, a self-written program called NaturalShow that was controlled using multi-touch on a touch screen. Not a PowerPoint-killer, but impressive nevertheless. The (excellent) talk itself was kind of eye-opening in regard to what “multi-touch support” on various platforms (WPF, Silverlight, Windows Phone) actually means.   Treat your Content Right The talk by Tiffani Jones Brown wasn’t even on my planned schedule, but somehow I ended up in that session – and it was great. And even for people who don’t necessarily have to write content for websites, some points made by Tiffani are valid in many places, notably wherever you put texts with more than a single word into your UI. Creating Effective Info Viz in Microsoft Silverlight The last session of MIX10 I attended was kind of disappointing. At first things were very promising, with Matthias Shapiro giving a brief but well-structured introduction to info graphics and interactive visualizations. Then the live-coding began and while the result was interesting, too much time was spend on wrestling to get the code working. Ending earlier than planned, the talk was a bit light on actual content, but at least it included a nice list of resources. Conclusion It could be felt all across MIX10, UIs will take a huge leap forward; in fact, there are enough examples that have already. People who both have the technical know-how and at least a basic understanding of design (“literacy” as Bill Buxton called it) are in high demand. The concept of the MIX conference and initiatives like design.toolbox shows that Microsoft understands very well that frontend developers have to acquire new knowledge besides knowing how to hack code and putting buttons on a form. There are extremely exciting times before us, with lots of opportunity for those who are eager to develop their skills, that is for sure.

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• Book Review - Programming Windows Azure by Siriram Krishnan

  - by BuckWoody

  As part of my professional development, I’ve created a list of books to read throughout the year, starting in June of 2011. This a review of the first one, called Programming Windows Azure by Siriram Krishnan. You can find my entire list of books I’m reading for my career here: http://blogs.msdn.com/b/buckwoody/archive/2011/06/07/head-in-the-clouds-eyes-on-the-books.aspx  Why I Chose This Book: As part of my learning style, I try to read multiple books about a single subject. I’ve found that at least 3 books are necessary to get the right amount of information to me. This is a “technical” work, meaning that it deals with technology and not business, writing or other facets of my career. I’ll have a mix of all of those as I read along. I chose this work in addition to others I’ve read since it covers everything from an introduction to more advanced topics in a single book. It also has some practical examples of actually working with the product, particularly on storage. Although it’s dated, many examples normally translate. I also saw that it had pretty good reviews. What I learned: I learned a great deal about storage, and many useful code snippets. I do think that there could have been more of a focus on the application fabric - but of course that wasn’t as mature a feature when this book was written. I learned some great architecture examples, and in one section I learned more about encryption. In that example, however, I would rather have seen the examples go the other way - the book focused on moving data from on-premise to Azure storage in an encrypted fashion. Using the Application Fabric I would rather see sensitive data left in a hybrid fashion on premise, and connect to for the Azure application. Even so, the examples were very useful. If you’re looking for a good “starter” Azure book, this is a good choice. I also recommend the last chapter as a quick read for a DBA, or Database Administrator. It’s not very long, but useful. Note that the limits described are incorrect - which is one of the dangers of reading a book about any cloud offering. The services offered are updated so quickly that the information is in constant danger of being “stale”. Even so, I found this a useful book, which I believe will help me work with Azure better. Raw Notes: I take notes as I read, calling that process “reading with a pencil”. I find that when I do that I pay attention better, and record some things that I need to know later. I’ll take these notes, categorize them into a OneNote notebook that I synchronize in my Live.com account, and that way I can search them from anywhere. I can even read them on the web, since the Live.com has a OneNote program built in. Note that these are the raw notes, so they might not make a lot of sense out of context - I include them here so you can watch my though process. Programming Windows Azure by Siriram Krishnan: Learning about how to select applications suitable for Distributed Technology. Application Fabric gets the least attention; probably because it was newer at the time. Very clear (Chapter One) Good foundation Background and history, but not too much I normally arrange my descriptions differently, starting with the use-cases and moving to physicality, but this difference helps me. Interesting that I am reading this using Safari Books Online, which uses many of these concepts. Taught me some new aspects of a Hypervisor – very low-level information about the Azure Fabric (not to be confused with the Application Fabric feature) (Chapter Two) Good detail of what is included in the SDK. Even more is available now. CS = Cloud Service (Chapter 3) Place Storage info in the configuration file, since it can be streamed in-line with a running app. Ditto for logging, and keep separated configs for staging and testing. Easy-switch in and switch out.  (Chapter 4) There are two Runtime API’s, one of external and one for internal. Realizing how powerful this paradigm really is. Some places seem light, and to drop off but perhaps that’s best. Managing API is not charged, which is nice. I don’t often think about the price, until it comes to an actual deployment (Chapter 5) Csmanage is something I want to dig into deeper. API requires package moves to Blob storage first, so it needs a URL. Csmanage equivalent can be written in Unix scripting using openssl. Upgrades are possible, and you use the upgradeDomainCount attribute in the Service-Definition.csdef file  Always use a low-privileged account to test on the dev fabric, since Windows Azure runs in partial trust. Full trust is available, but can be dangerous and must be well-thought out. (Chapter 6) Learned how to run full CMD commands in a web window – not that you would ever do that, but it was an interesting view into those links. This leads to a discussion on hosting other runtimes (such as Java or PHP) in Windows Azure. I got an expanded view on this process, although this is where the book shows its age a little. Books can be a problem for Cloud Computing for this reason – things just change too quickly. Windows Azure storage is not eventually consistent – it is instantly consistent with multi-phase commit. Plumbing for this is internal, not required to code that. (Chapter 7) REST API makes the service interoperable, hybrid, and consistent across code architectures. Nicely done. Use affinity groups to keep data and code together. Side note: e-book readers need a common “notes” feature. There’s a decent quick description of REST in this chapter. Learned about CloudDrive code – PowerShell sample that mounts Blob storage as a local provider. Works against Dev fabric by default, can be switched to Account. Good treatment in the storage chapters on the differences between using Dev storage and Azure storage. These can be mitigated. No, blobs are not of any size or number. Not a good statement (Chapter 8) Blob storage is probably Azure’s closest play to Infrastructure as a Service (Iaas). Blob change operations must be authenticated, even when public. Chapters on storage are pretty in-depth. Queue Messages are base-64 encoded (Chapter 9) The visibility timeout ensures processing of message in a disconnected system. Order is not guaranteed for a message, so if you need that set an increasing number in the queue mechanism. While Queues are accessible via REST, they are not public and are secured by default. Interesting – the header for a queue request includes an estimated count. This can be useful to create more worker roles in a dynamic system. Each Entity (row) in the Azure Table service is atomic – all or nothing. (Chapter 10) An entity can have up to 255 Properties  Use “ID” for the class to indicate the key value, or use the [DataServiceKey] Attribute.  LINQ makes working with the Azure Table Service much easier, although Interop is certainly possible. Good description on the process of selecting the Partition and Row Key.  When checking for continuation tokens for pagination, include logic that falls out of the check in case you are at the last page.  On deleting a storage object, it is instantly unavailable, however a background process is dispatched to perform the physical deletion. So if you want to re-create a storage object with the same name, add retry logic into the code. Interesting approach to deleting an index entity without having to read it first – create a local entity with the same keys and apply it to the Azure system regardless of change-state.  Although the “Indexes” description is a little vague, it’s interesting to see a Folding and Stemming discussion a-la the Porter Stemming Algorithm. (Chapter 11)  Presents a better discussion of indexes (at least inverted indexes) later in the chapter. Great treatment for DBA’s in Chapter 11. We need to work on getting secondary indexes in Table storage. There is a limited form of transactions called “Entity Group Transactions” that, although they have conditions, makes a transactional system more possible. Concurrency also becomes an issue, but is handled well if you’re using Data Services in .NET. It watches the Etag and allows you to take action appropriately. I do not recommend using Azure as a location for secure backups. In fact, I would rather have seen the examples in (Chapter 12) go the other way, showing how data could be brought back to a local store as a DR or HA strategy. Good information on cryptography and so on even so. Chapter seems out of place, and should be combined with the Blob chapter.  (Chapter 13) on SQL Azure is dated, although the base concepts are OK.  Nice example of simple ADO.NET access to a SQL Azure (or any SQL Server Really) database.  

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• Caching NHibernate Named Queries

  - by TStewartDev

  I recently started a new job and one of my first tasks was to implement a "popular products" design. The parameters were that it be done with NHibernate and be cached for 24 hours at a time because the query will be pretty taxing and the results do not need to be constantly up to date. This ended up being tougher than it sounds. The database schema meant a minimum of four joins with filtering and ordering criteria. I decided to use a stored procedure rather than letting NHibernate create the SQL for me. Here is a summary of what I learned (even if I didn't ultimately use all of it): You can't, at the time of this writing, use Fluent NHibernate to configure SQL named queries or imports You can return persistent entities from a stored procedure and there are a couple ways to do that You can populate POCOs using the results of a stored procedure, but it isn't quite as obvious You can reuse your named query result mapping other places (avoid duplication) Caching your query results is not at all obvious Testing to see if your cache is working is a pain NHibernate does a lot of things right. Having unified, up-to-date, comprehensive, and easy-to-find documentation is not one of them. By the way, if you're new to this, I'll use the terms "named query" and "stored procedure" (from NHibernate's perspective) fairly interchangeably. Technically, a named query can execute any SQL, not just a stored procedure, and a stored procedure doesn't have to be executed from a named query, but for reusability, it seems to me like the best practice. If you're here, chances are good you're looking for answers to a similar problem. You don't want to read about the path, you just want the result. So, here's how to get this thing going. The Stored Procedure NHibernate has some guidelines when using stored procedures. For Microsoft SQL Server, you have to return a result set. The scalar value that the stored procedure returns is ignored as are any result sets after the first. Other than that, it's nothing special. CREATE PROCEDURE GetPopularProducts @StartDate DATETIME, @MaxResults INT AS BEGIN SELECT [ProductId], [ProductName], [ImageUrl] FROM SomeTableWithJoinsEtc END The Result Class - PopularProduct You have two options to transport your query results to your view (or wherever is the final destination): you can populate an existing mapped entity class in your model, or you can create a new entity class. If you go with the existing model, the advantage is that the query will act as a loader and you'll get full proxied access to the domain model. However, this can be a disadvantage if you require access to the related entities that aren't loaded by your results. For example, my PopularProduct has image references. Unless I tie them into the query (thus making it even more complicated and expensive to run), they'll have to be loaded on access, requiring more trips to the database. Since we're trying to avoid trips to the database by using a second-level cache, we should use the second option, which is to create a separate entity for results. This approach is (I believe) in the spirit of the Command-Query Separation principle, and it allows us to flatten our data and optimize our report-generation process from data source to view. public class PopularProduct { public virtual int ProductId { get; set; } public virtual string ProductName { get; set; } public virtual string ImageUrl { get; set; } } The NHibernate Mappings (hbm) Next up, we need to let NHibernate know about the query and where the results will go. Below is the markup for the PopularProduct class. Notice that I'm using the <resultset> element and that it has a name attribute. The name allows us to drop this into our query map and any others, giving us reusability. Also notice the <import> element which lets NHibernate know about our entity class. <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"> <import class="PopularProduct, Infrastructure.NHibernate, Version=1.0.0.0"/> <resultset name="PopularProductResultSet"> <return-scalar column="ProductId" type="System.Int32"/> <return-scalar column="ProductName" type="System.String"/> <return-scalar column="ImageUrl" type="System.String"/> </resultset> </hibernate-mapping>  And now the PopularProductsMap: <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"> <sql-query name="GetPopularProducts" resultset-ref="PopularProductResultSet" cacheable="true" cache-mode="normal"> <query-param name="StartDate" type="System.DateTime" /> <query-param name="MaxResults" type="System.Int32" /> exec GetPopularProducts @StartDate = :StartDate, @MaxResults = :MaxResults </sql-query> </hibernate-mapping>  The two most important things to notice here are the resultset-ref attribute, which links in our resultset mapping, and the cacheable attribute. The Query Class – PopularProductsQuery So far, this has been fairly obvious if you're familiar with NHibernate. This next part, maybe not so much. You can implement your query however you want to; for me, I wanted a self-encapsulated Query class, so here's what it looks like: public class PopularProductsQuery : IPopularProductsQuery { private static readonly IResultTransformer ResultTransformer; private readonly ISessionBuilder _sessionBuilder;   static PopularProductsQuery() { ResultTransformer = Transformers.AliasToBean<PopularProduct>(); }   public PopularProductsQuery(ISessionBuilder sessionBuilder) { _sessionBuilder = sessionBuilder; }   public IList<PopularProduct> GetPopularProducts(DateTime startDate, int maxResults) { var session = _sessionBuilder.GetSession(); var popularProducts = session .GetNamedQuery("GetPopularProducts") .SetCacheable(true) .SetCacheRegion("PopularProductsCacheRegion") .SetCacheMode(CacheMode.Normal) .SetReadOnly(true) .SetResultTransformer(ResultTransformer) .SetParameter("StartDate", startDate.Date) .SetParameter("MaxResults", maxResults) .List<PopularProduct>();   return popularProducts; } }  Okay, so let's look at each line of the query execution. The first, GetNamedQuery, matches up with our NHibernate mapping for the sql-query. Next, we set it as cacheable (this is probably redundant since our mapping also specified it, but it can't hurt, right?). Then we set the cache region which we'll get to in the next section. Set the cache mode (optional, I believe), and my cache is read-only, so I set that as well. The result transformer is very important. This tells NHibernate how to transform your query results into a non-persistent entity. You can see I've defined ResultTransformer in the static constructor using the AliasToBean transformer. The name is obviously leftover from Java/Hibernate. Finally, set your parameters and then call a result method which will execute the query. Because this is set to cached, you execute this statement every time you run the query and NHibernate will know based on your parameters whether to use its cached version or a fresh version. The Configuration – hibernate.cfg.xml and Web.config You need to explicitly enable second-level caching in your hibernate configuration: <hibernate-configuration xmlns="urn:nhibernate-configuration-2.2"> <session-factory> [...] <property name="dialect">NHibernate.Dialect.MsSql2005Dialect</property> <property name="cache.provider_class">NHibernate.Caches.SysCache.SysCacheProvider,NHibernate.Caches.SysCache</property> <property name="cache.use_query_cache">true</property> <property name="cache.use_second_level_cache">true</property> [...] </session-factory> </hibernate-configuration> Both properties "use_query_cache" and "use_second_level_cache" are necessary. As this is for a web deployement, we're using SysCache which relies on ASP.NET's caching. Be aware of this if you're not deploying to the web! You'll have to use a different cache provider. We also need to tell our cache provider (in this cache, SysCache) about our caching region: <syscache> <cache region="PopularProductsCacheRegion" expiration="86400" priority="5" /> </syscache> Here I've set the cache to be valid for 24 hours. This XML snippet goes in your Web.config (or in a separate file referenced by Web.config, which helps keep things tidy). The Payoff That should be it! At this point, your queries should run once against the database for a given set of parameters and then use the cache thereafter until it expires. You can, of course, adjust settings to work in your particular environment. Testing Testing your application to ensure it is using the cache is a pain, but if you're like me, you want to know that it's actually working. It's a bit involved, though, so I'll create a separate post for it if comments indicate there is interest.

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• SQL SERVER – Weekly Series – Memory Lane – #003

  - by pinaldave

  Here is the list of curetted articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2006 This was the first year of my blogging and lots of new things I was learning as I go. I was indeed an infant in blogging a few years ago. However, as time passed by I have learned a lot. This year was year of experiments and new learning. 2007 Working as a full time DBA I often encoutered various errors and I started to learn how to avoid those error and document the same. ERROR Msg 5174 Each file size must be greater than or equal to 512 KB Whenever I see this error I wonder why someone is trying to attempt a database which is extremely small. Anyway, it does not matter what I think I keep on seeing this error often in industries. Anyway the solution of the error is equally interesting – just created larger database. Dilbert Humor This was very first encounter with database humor and I started to love it. It does not matter how many time we read this cartoon it does not get old. Generate Script with Data from Database – Database Publishing Wizard Generating schema script with data is one of the most frequently performed tasks among SQL Server Data Professionals. There are many ways to do the same. In the above article I demonstrated that how we can use the Database Publishing Wizard to accomplish the same. It was new to me at that time but I have not seen much of the adoption of the same still in the industry. Here is one of my videos where I demonstrate how we can generate data with schema. 2008 Delete Backup History – Cleanup Backup History Deleting backup history is important too but should be done carefully. If this is not carried out at regular interval there is good chance that MSDB will be filled up with all the old history. Every organization is different. Some would like to keep the history for 30 days and some for a year but there should be some limit. One should regularly archive the database backup history. South Asia MVP Open Days 2008 This was my very first year Microsoft MVP. I had Indeed big blast at the event and the fun was incredible. After this event I have attended many different MVP events but the fun and learning this particular event presented was amazing and just like me many others are not able to forget the same. Here are other links related to the event: South Asia MVP Open Day 2008 – Goa South Asia MVP Open Day 2008 – Goa – Day 1 South Asia MVP Open Day 2008 – Goa – Day 2 South Asia MVP Open Day 2008 – Goa – Day 3 2009 Enable or Disable Constraint  This is very simple script but I personally keep on forgetting it so I had blogged it. Till today, I keep on referencing this again and again as sometime a very little thing is hard to remember. Policy Based Management – Create, Evaluate and Fix Policies This article will cover the most spectacular feature of SQL 2008 – Policy-based management and how the configuration of SQL Server with policy-based management architecture can make a powerful difference. Policy based management is loaded with several advantages. It can help you implement various policies for reliable configuration of the system. It also provides additional administrative assistance to DBAs and helps them effortlessly manage various tasks of SQL Server across the enterprise. SQLPASS 2009 – My Very First SQPASS Experience Just Brilliant! I never had an experience such a thing in my life. SQL SQL and SQL – all around SQL! I am listing my own reasons here in order of importance to me. Networking with SQL fellows and experts Putting face to the name or avatar Learning and improving my SQL skills Understanding the structure of the largest SQL Server Professional Association Attending my favorite training sessions Since last time I have never missed a single time this event. This event is my favorite event and something keeps me going. Here are additional post related SQLPASS 2009. SQL PASS Summit, Seattle 2009 – Day 1 SQL PASS Summit, Seattle 2009 – Day 2 SQL PASS Summit, Seattle 2009 – Day 3 SQL PASS Summit, Seattle 2009 – Day 4 2010 Get All the Information of Database using sys.databases Even though we believe that we know everything about our database, we do not know a lot of things about our database. This little script enables us to know so many details about databases which we may not be familiar with. Run this on your server today and see how much you know your database. Reducing CXPACKET Wait Stats for High Transactional Database While engaging in a performance tuning consultation for a client, a situation occurred where they were facing a lot of CXPACKET Waits Stats. The client asked me if I could help them reduce this huge number of wait stats. I usually receive this kind of request from other client as well, but the important thing to understand is whether this question has any merits or benefits, or not. I discusses the same in this article – a bit long but insightful for sure. Error related to Database in Use There are so many database management operations in SQL Server which requires exclusive access to the database and it is not always possible to get it. When any database is online in SQL Server it either applications or system thread often accesses them. This means database can’t have exclusive access and the operations which required this access throws an error. There is very easy method to overcome this minor issue – a single line script can give you exclusive access to the database. Difference between DATETIME and DATETIME2 Developers have found the root reason of the problem when dealing with Date Functions – when data time values are converted (implicit or explicit) between different data types, which would lose some precision, so the result cannot match each other as expected. In this blog post I go over very interesting details and difference between DATETIME and DATETIME2 History of SQL Server Database Encryption I recently met Michael Coles and Rodeney Landrum the author of one of the kind book Expert SQL Server 2008 Encryption at SQLPASS in Seattle. During the conversation we ended up how Microsoft is evolving encryption technology. The same discussion lead to talking about history of encryption tools in SQL Server. Michale pointed me to page 18 of his book of encryption. He explicitly gave me permission to re-produce relevant part of history from his book. 2011 Functions FIRST_VALUE and LAST_VALUE with OVER clause and ORDER BY Some time an interesting feature and smart audience make a total difference in places. From last two days, I have been writing on SQL Server 2012 feature FIRST_VALUE and LAST_VALUE. I created a puzzle which was very interesting and got many people attempt to resolve it. It was based on following two articles: Introduction to FIRST_VALUE and LAST_VALUE Introduction to FIRST_VALUE and LAST_VALUE with OVER clause I even provided the hint about how one can solve this problem. The best part was many people solved the problem without using hints! Try your luck!  A Real Story of Book Getting ‘Out of Stock’ to A 25% Discount Story Available This is a great problem and everybody would love to have it. We had it and we loved it. Our book got out of stock in 48 hours of releasing and stocks were empty. We faced many issues and learned many valuable lessons. Some we were able to avoid in the future and some we are still facing it as those problems have no solutions. However, since that day – our books never gone out of stock. This inspiring learning story for us and I am confident that you will love to read it as well. Introduction to LEAD and LAG – Analytic Functions Introduced in SQL Server 2012 SQL Server 2012 introduces new analytical function LEAD() and LAG(). This function accesses data from a subsequent row (for lead) and previous row (for lag) in the same result set without the use of a self-join . It will be very difficult to explain this in words so I will attempt small example to explain you this function. I had a fantastic time writing this blog post and I am very confident when you read it, you will like the same. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• How I understood monads, part 1/2: sleepless and self-loathing in Seattle

  - by Bertrand Le Roy

  For some time now, I had been noticing some interest for monads, mostly in the form of unintelligible (to me) blog posts and comments saying “oh, yeah, that’s a monad” about random stuff as if it were absolutely obvious and if I didn’t know what they were talking about, I was probably an uneducated idiot, ignorant about the simplest and most fundamental concepts of functional programming. Fair enough, I am pretty much exactly that. Being the kind of guy who can spend eight years in college just to understand a few interesting concepts about the universe, I had to check it out and try to understand monads so that I too can say “oh, yeah, that’s a monad”. Man, was I hit hard in the face with the limitations of my own abstract thinking abilities. All the articles I could find about the subject seemed to be vaguely understandable at first but very quickly overloaded the very few concept slots I have available in my brain. They also seemed to be consistently using arcane notation that I was entirely unfamiliar with. It finally all clicked together one Friday afternoon during the team’s beer symposium when Louis was patient enough to break it down for me in a language I could understand (C#). I don’t know if being intoxicated helped. Feel free to read this with or without a drink in hand. So here it is in a nutshell: a monad allows you to manipulate stuff in interesting ways. Oh, OK, you might say. Yeah. Exactly. Let’s start with a trivial case: public static class Trivial { public static TResult Execute<T, TResult>( this T argument, Func<T, TResult> operation) { return operation(argument); } } This is not a monad. I removed most concepts here to start with something very simple. There is only one concept here: the idea of executing an operation on an object. This is of course trivial and it would actually be simpler to just apply that operation directly on the object. But please bear with me, this is our first baby step. Here’s how you use that thing: "some string" .Execute(s => s + " processed by trivial proto-monad.") .Execute(s => s + " And it's chainable!"); What we’re doing here is analogous to having an assembly chain in a factory: you can feed it raw material (the string here) and a number of machines that each implement a step in the manufacturing process and you can start building stuff. The Trivial class here represents the empty assembly chain, the conveyor belt if you will, but it doesn’t care what kind of raw material gets in, what gets out or what each machine is doing. It is pure process. A real monad will need a couple of additional concepts. Let’s say the conveyor belt needs the material to be processed to be contained in standardized boxes, just so that it can safely and efficiently be transported from machine to machine or so that tracking information can be attached to it. Each machine knows how to treat raw material or partly processed material, but it doesn’t know how to treat the boxes so the conveyor belt will have to extract the material from the box before feeding it into each machine, and it will have to box it back afterwards. This conveyor belt with boxes is essentially what a monad is. It has one method to box stuff, one to extract stuff from its box and one to feed stuff into a machine. So let’s reformulate the previous example but this time with the boxes, which will do nothing for the moment except containing stuff. public class Identity<T> { public Identity(T value) { Value = value; } public T Value { get; private set;} public static Identity<T> Unit(T value) { return new Identity<T>(value); } public static Identity<U> Bind<U>( Identity<T> argument, Func<T, Identity<U>> operation) { return operation(argument.Value); } } Now this is a true to the definition Monad, including the weird naming of the methods. It is the simplest monad, called the identity monad and of course it does nothing useful. Here’s how you use it: Identity<string>.Bind( Identity<string>.Unit("some string"), s => Identity<string>.Unit( s + " was processed by identity monad.")).Value That of course is seriously ugly. Note that the operation is responsible for re-boxing its result. That is a part of strict monads that I don’t quite get and I’ll take the liberty to lift that strange constraint in the next examples. To make this more readable and easier to use, let’s build a few extension methods: public static class IdentityExtensions { public static Identity<T> ToIdentity<T>(this T value) { return new Identity<T>(value); } public static Identity<U> Bind<T, U>( this Identity<T> argument, Func<T, U> operation) { return operation(argument.Value).ToIdentity(); } } With those, we can rewrite our code as follows: "some string".ToIdentity() .Bind(s => s + " was processed by monad extensions.") .Bind(s => s + " And it's chainable...") .Value; This is considerably simpler but still retains the qualities of a monad. But it is still pointless. Let’s look at a more useful example, the state monad, which is basically a monad where the boxes have a label. It’s useful to perform operations on arbitrary objects that have been enriched with an attached state object. public class Stateful<TValue, TState> { public Stateful(TValue value, TState state) { Value = value; State = state; } public TValue Value { get; private set; } public TState State { get; set; } } public static class StateExtensions { public static Stateful<TValue, TState> ToStateful<TValue, TState>( this TValue value, TState state) { return new Stateful<TValue, TState>(value, state); } public static Stateful<TResult, TState> Execute<TValue, TState, TResult>( this Stateful<TValue, TState> argument, Func<TValue, TResult> operation) { return operation(argument.Value) .ToStateful(argument.State); } } You can get a stateful version of any object by calling the ToStateful extension method, passing the state object in. You can then execute ordinary operations on the values while retaining the state: var statefulInt = 3.ToStateful("This is the state"); var processedStatefulInt = statefulInt .Execute(i => ++i) .Execute(i => i * 10) .Execute(i => i + 2); Console.WriteLine("Value: {0}; state: {1}", processedStatefulInt.Value, processedStatefulInt.State); This monad differs from the identity by enriching the boxes. There is another way to give value to the monad, which is to enrich the processing. An example of that is the writer monad, which can be typically used to log the operations that are being performed by the monad. Of course, the richest monads enrich both the boxes and the processing. That’s all for today. I hope with this you won’t have to go through the same process that I did to understand monads and that you haven’t gone into concept overload like I did. Next time, we’ll examine some examples that you already know but we will shine the monadic light, hopefully illuminating them in a whole new way. Realizing that this pattern is actually in many places but mostly unnoticed is what will enable the truly casual “oh, yes, that’s a monad” comments. Here’s the code for this article: http://weblogs.asp.net/blogs/bleroy/Samples/Monads.zip The Wikipedia article on monads: http://en.wikipedia.org/wiki/Monads_in_functional_programming This article was invaluable for me in understanding how to express the canonical monads in C# (interesting Linq stuff in there): http://blogs.msdn.com/b/wesdyer/archive/2008/01/11/the-marvels-of-monads.aspx

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