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• object not getting released in iphone

  - by Jaimin

  i m writing this code in my code to store the data in database.. Search *objSearchDetail = [[Search alloc] init]; objSearchDetail = [xmlResponseDetail objectAtIndex:i]; sql = "INSERT INTO tblsearchdetail(tblrecentsearch_id,name,address,email,url,street,postcode,city,telephone,mobile) VALUES(?,?,?,?,?,?,?,?,?,?)"; returnValue = sqlite3_prepare_v2(database, sql, -1, &insertStatement, NULL); if(returnValue == SQLITE_OK){ sqlite3_bind_int(insertStatement, 1, intLastRecentSearchId); sqlite3_bind_text(insertStatement, 2, [objSearchDetail.strName UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 3, [objSearchDetail.strAddress UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 4, [objSearchDetail.strEmail UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 5, [objSearchDetail.strUrl UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 6, [objSearchDetail.strStreet UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 7, [objSearchDetail.strPostCode UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 8, [objSearchDetail.strPlace UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 9, [objSearchDetail.strTelephone UTF8String], -1,SQLITE_TRANSIENT); sqlite3_bind_text(insertStatement, 10, [objSearchDetail.strMobile UTF8String], -1,SQLITE_TRANSIENT); if(sqlite3_step(insertStatement)==SQLITE_DONE) { //Data; } } NSLog(@"count %d",[objSearchDetail retainCount]); [objSearchDetail release]; now the nslog shows refrence count as 2 so even if i release the refrence count will still be one and the object will not be destroyed.. plz help me....

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• How to obtain value of auto_increment field in Access linked to MySQL?

  - by Cruachan

  I'm trying to modify and existing Access application to use MySQL as a database via ODBC with the minimal amount of recoding. The current code will often insert a new record using DAO then obtain the ID by using LastModified. This doesn't work with MySQL. Instead I'm trying to use the approach using SELECT * FROM tbl_name WHERE auto_col IS NULL Suggested for Access in the MySQL documentation. However if I set up a sample table consisting of just an id and text data field and execute this CurrentDb.Execute ("INSERT INTO tbl_scratch (DATA) VALUES ('X')") Set rst = CurrentDb.OpenRecordset("SELECT id FROM tbl_scratch WHERE id IS NULL") myid = rst!id Id is returned as null. However if I execute INSERT INTO tbl_scratch (DATA) VALUES ('X'); SELECT id FROM tbl_scratch WHERE id IS NULL; using a direct MySQL editor then id is returned correctly, so my database and approach is fine but my implementation inside Access must be incorrect. Frustratingly the MySQL documentation gives the SQL statement to retrieve the id as an example that works in Access (as it states LAST_INSERT_ID() doesn't) but gives no further details. How might I fix this?

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• Why represent shopping carts and order invoices differently in a domain model?

  - by Todd

  I've built some shopping cart systems in the past, but I always designed them such that the final order invoice is just a shopping cart that has been marked as "purchased". All the logic for adding/removing/changing items in a cart is also the logic for the order. All data is stored in the same tables in the database. But it seems this is not the proper way to design an e-commerce site.. Can someone explain the benefit of separating the shopping cart from invoices in the domain model? It seems to me this would lead to a lot of duplicated code, an extra set of tables in the database, and make it harder to maintain in the event the system need to start accommodating more complicated orders (like specifying selected options for an item which may or may not change the price/availability/shipping time of the order). I'm assuming I just haven't seen the light, as every book and other example I see seems to separate these two seemingly similar concerns -- but I can't find any explanation as to the benefit of doing such! It's also the case in the systems that I design that changes are often made after the initial order is confirmed. It's not uncommon for items to be removed, replaced, or added afterwards (but prior to fulfillment).

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• How to save errors with the handleError in CakePHP 2.0?

  - by jags1988cr

  I have a big problem. Well, I'm trying to save the errors that happen in my web application. For example (only a example), if I make a division by zero, or happens an error in a query or something like that. So, I wanna catch that and save it in the database. But the handleError of CakePHP is static, so I can't use $this-MyModel-saveError(...). In my /app/Lib/AppError.php I have this: class AppError extends ErrorHandler { public $uses = array('Errors.Error'); public static function handleError($code, $description, $file = null, $line = null, $context = null) { //This print the error: echo "Code: ".$code." Description: ".$description." File: ".$file." Line: ".$line."<br>"; //I want to do this, (save to the database): $this->Error->saveError($code, $description, $file, $line); } } Without the $this-Error-saveError($code, $description, $file, $line); it works but I not only want to show the error. I think need an example or something like that. Please help me. Regards and thank you. Thanks... P.D.: Sorry for the English, I'm an english student...

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• Fix DB duplicate entries (MySQL bug)

  - by Silence

  I'm using MySQL 4.1. Some tables have duplicates entries that go against the constraints. When I try to group rows, MySQL doesn't recognise the rows as being similar. Example: Table A has a column "Name" with the Unique proprety. The table contains one row with the name 'Hach?' and one row with the same name but a square at the end instead of the '?' (which I can't reproduce in this textfield) A "Group by" on these 2 rows return 2 separate rows This cause several problems including the fact that I can't export and reimport the database. On reimporting an error mentions that a Insert has failed because it violates a constraint. In theory I could try to import, wait for the first error, fix the import script and the original DB, and repeat. In pratice, that would take forever. Is there a way to list all the anomalies or force the database to recheck constraints (and list all the values/rows that go against them) ? I can supply the .MYD file if it can be helpful.

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• How to configure multiple mappings using FluentHibernate?

  - by chris.baglieri

  First time rocking it with NHibernate/Fluent so apologies in advance if this is a naive question. I have a set of Models I want to map. When I create my session factory I'm trying to do all mappings at once. I am not using auto-mapping (though I may if what I am trying to do ends up being more painful than it ought to be). The problem I am running into is that it seems only the top map is taking. Given the code snippet below and running a unit test that attempts to save 'bar', it fails and checking the logs I see NHibernate is trying to save a bar entity to the foo table. While I suspect it's my mappings it could be something else that I am simply overlooking. Code that creates the session factory (note I've also tried separate calls into .Mappings): Fluently.Configure().Database(MsSqlConfiguration.MsSql2008 .ConnectionString(c => c .Server(@"localhost\SQLEXPRESS") .Database("foo") .Username("foo") .Password("foo"))) .Mappings(m => { m.FluentMappings.AddFromAssemblyOf<FooMap>() .Conventions.Add(FluentNHibernate.Conventions.Helpers .Table.Is(x => "foos")); m.FluentMappings.AddFromAssemblyOf<BarMap>() .Conventions.Add(FluentNHibernate.Conventions.Helpers .Table.Is(x => "bars")); }) .BuildSessionFactory(); Unit test snippet: using (var session = Data.SessionHelper.SessionFactory.OpenSession()) { var bar = new Bar(); session.Save(bar); Assert.NotNull(bar.Id); }

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• How do I efficiently locate key-value pairs in a multi-dimensional PHP array?

  - by Kyle Noland

  I have an array in PHP as a result of the following query to a Wordpress database: SELECT * FROM wp_postmeta WHERE post_id = :id I am returned a multidimensional array that looks like this: Array ( [0] => Array ( [meta_id] => 380 [post_id] => 72 [meta_key] => _edit_last [meta_value] => 1 ) ... etc. What is the best way to find a particular key-value pair in this array? For instance, how would I located the row where [meta_key] = event_name so that I can extract that same row's [meta_value] value into a PHP variable? I realize I could turn this into many individual MySQL queries. Does anyone have an opinion of the efficiency of doing 10 SQL queries in a row rather than searching the array 10 times? I would think since the array is in memory, that will be the fastest method to find the values I need. Alternatively, is there a better way to query the database from the beginning so that my result set is formatted in a way that is easier to search?

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• Can you dynamically combine multiple conditional functions into one in Python?

  - by erich

  I'm curious if it's possible to take several conditional functions and create one function that checks them all (e.g. the way a generator takes a procedure for iterating through a series and creates an iterator). The basic usage case would be when you have a large number of conditional parameters (e.g. "max_a", "min_a", "max_b", "min_b", etc.), many of which could be blank. They would all be passed to this "function creating" function, which would then return one function that checked them all. Below is an example of a naive way of doing what I'm asking: def combining_function(max_a, min_a, max_b, min_b, ...): f_array = [] if max_a is not None: f_array.append( lambda x: x.a < max_a ) if min_a is not None: f_array.append( lambda x: x.a > min_a ) ... return lambda x: all( [ f(x) for f in f_array ] ) What I'm wondering is what is the most efficient to achieve what's being done above? It seems like executing a function call for every function in f_array would create a decent amount of overhead, but perhaps I'm engaging in premature/unnecessary optimization. Regardless, I'd be interested to see if anyone else has come across usage cases like this and how they proceeded. Also, if this isn't possible in Python, is it possible in other (perhaps more functional) languages?

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• Update PageTitle on Timer.Tick

  - by sohum

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

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• Sync data between a windows desktop app and windows mobile client app

  - by Chris W

  I need to knock up a very quick prototype/proof of concept application to demo to someone within the next couple of days so I've minimal time to research this as fully as I normally would. The set-up is a very simple database application running on a laptop - will only ever be a single user updating a couple of tables so I was thinking of knocking up a basic Win Forms app against SQL Compact. Visual Studio's auto generated data grid edit screens will be fine with a little customisation. The second aspect is to then add a windows mobile client application that can pull data from both tables stored on the laptop, edit some data and insert some extra rows before sending the changes back to the laptop copy of the database. I've not done any WinMo development so what's the best approach for me to look at. Is it easy enough to sync data between the two databases when the WinMo device is connected to the laptop with USB? Most of the samples I've looked at so far seem to be syncing SQL Compact with SQL Standard using IIS which seems a bit overkill. The volumes of data to be synced are so small that I can easily write some manual sync code if it's easy for me to query/update the Compact DB from the laptop application when the device is connected.

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• Mixing has_one and has_and_belongs_to_many associations

  - by Thomas

  I'm trying to build a database of urls(links). I have a Category model that has and belongs to many Links. Here's the migration I ran: class CreateLinksCategories < ActiveRecord::Migration def self.up create_table :links_categories, :id => false do |t| t.references :link t.references :category end end def self.down drop_table :links_categories end end Here's the Link model: class Link < ActiveRecord::Base validates :path, :presence => true, :format => { :with => /^(#{URI::regexp(%w(http https))})$|^$/ } validates :name, :presence => true has_one :category end Here's the category model: class Category < ActiveRecord::Base has_and_belongs_to_many :links end And here's the error the console kicked back when I tried to associate the first link with the first category: >>link = Link.first => #<Link id: 1, path: "http://www.yahoo.com", created_at: "2011-01-10... >>category = Category.first => #<category id : 1, name: "News Site", created_at: "2011-01-11... >>link.category << category => ActiveRecord::StatementInvalid: SQLite3::Exception: no such column : categories.link_id: Are my associations wrong or am I missing something in the database? I expected it to find the links_categories table. Any help is appreciated.

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• How does Access 2007's moveNext/moveFirst/, etc., feature work?

  - by Chris M

  I'm not an Access expert, but am an SQL expert. I inherited an Access front-end referencing a SQL 2005 database that worked OK for about 5000 records, but is failing miserably for 800k records... Behind the scenes in the SQL profiler & activity manager I see some kind of Access query like: SELECT "MS1"."id" FROM "dbo"."customer" "MS1" ORDER BY "MS1"."id" The MS prefix doesn't appear in any Access code I can see. I'm suspicious of the built-in Access navigation code: DoCmd.GoToRecord , , acNext The GoToRecord has AcRecord constant, which includes things like acFirst, acLast, acNext, acPrevious and acGoTo. What does it mean in a database context to move to the "next" record? This particular table uses an identity column as the PK, so is it internally grabbing all the IDs and then moving to the one that is the next highest??? If so, how would it work if a table was comprised of three different fields for the PK? Or am I on the wrong track, and something else in Access is calling that statement? Unfortunately I see a ton of prepared statements in the profiler. THanks!

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• How to change Hibernate´s auto persistance strategy

  - by Kristofer Borgstrom

  I just noted that my hibernate entities are automatically persisted to the database (or at least to cache) before I call any save() or update() method. To me this is a pretty strange default behavior but ok, as long as I can disable it, it´s fine. The problem I have is I want to update my entity´s state (from 1 to 2) only if the entity in the database still has the state it had when I retrieved [1] (this is to eliminate concurrency issues when another server is updating this same object). For this reason I have created a custom NamedQuery that will only update the entity if state is 1. So here is some pseudo-code: //Get the entity Entity item = dao.getEntity(); item.getState(); //==1 //Update the entity item.setState(2); //Here is the problem, this effectively changes the state of my entity braking my query that verifies that state is still == 1. dao.customUpdate(item); //Returns 0 rows changes since state != 1. So, how do I make sure the setters don´t change the state in cache/db? Thanks, Kristofer

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• What is the best way to go about grouping rows by the same timestamp?

  - by Luke

  Hello all. I am looking for some advice. I have rows of data in the database that i want to group together. There is a timestamp involved. That column is called date. What is the best way to go about grouping rows by the same timestamp. EDITED..... <? $result = mysql_query("SELECT * FROM ".TBL_FIXTURES." ORDER BY date"); $current_week = null; while ($row = mysql_fetch_assoc($result)) { if ($row['date'] != $current_week) { $current_week = $row['date']; echo 'Week ' . $current_week .': '; } echo $row['home_user']; echo $row['home_team']; echo $row['away_user']; echo $row['away_team']; } ?> I have this code. What i am trying to do is organise each round of fixtures in a row with a title Week 1 - date. I want Week 1 and the date and all fixtures with that date displayed. Then move onto week 2 and the date and all fixtures again. This should be done for every fixture in the database, so if there are 6 rounds of fixtures, there will be 6 dates and therefore 6 blocks of fixtures.. Please help, thanks

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• Security strategies for storing password on disk

  - by Mike

  I am building a suite of batch jobs that require regular access to a database, running on a Solaris 10 machine. Because of (unchangable) design constraints, we are required use a certain program to connect to it. Said interface requires us to pass a plain-text password over a command line to connect to the database. This is a terrible security practice, but we are stuck with it. I am trying to make sure things are properly secured on our end. Since the processing is automated (ie, we can't prompt for a password), and I can't store anything outside the disk, I need a strategy for storing our password securely. Here are some basic rules The system has multiple users. We can assume that our permissions are properly enforced (ie, if a file with a is chmod'd to 600, it won't be publically readable) I don't mind anyone with superuser access looking at our stored password Here is what i've got so far Store password in password.txt $chmod 600 password.txt Process reads from password.txt when it's needed Buffer overwritten with zeros when it's no longer needed Although I'm sure there is a better way.

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• Custom Drupal Module not creating any tables

  - by Anthony

  Anything specific I need in the module file? Install File function module_install() { //lets create the school database $create_table_sql = "CREATE TABLE IF NOT EXISTS `table1` ( id int(11) NOT NULL, principal_name varchar(300) NOT NULL, school_name varchar(300) NOT NULL, address1 varchar(300) NOT NULL, address2 varchar(300) NOT NULL, city varchar(300) NOT NULL, computer_serial_no varchar(300) NOT NULL, state varchar(200) NOT NULL, uid int(200) NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1"; db_query($create_table_sql); //lets create the student database $create_table_sql = "CREATE TABLE IF NOT EXISTS table2 ( id int(11) NOT NULL, principal_name varchar(300) NOT NULL, school_name varchar(300) NOT NULL, address1 varchar(300) NOT NULL, address2 varchar(300) NOT NULL, city varchar(300) NOT NULL, computer_serial_no varchar(300) NOT NULL, state varchar(200) NOT NULL, uid int(200) NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1"; db_query($create_table_sql); } /** * _UNINSTALL hook * * This function is run to uninstall the module. * */ function module_uninstall() { // Delete the DB db_query("drop table table1"); db_query("drop table table2"); } Info File Just in Case ; $Id$ name = My Module description = This module deals with blah blah package = Somepackage core = 6.x version = "6.x-1.0" core = "6.x"

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• sed script to remove file name duplicates

  - by dma_k

  Dear community, I hope the below task will be very easy for sed lovers. I am not sed-guru, but I need to express the following task in sed, as sed is more popular on Linux systems. The input text stream is something which is produced by "make depends" and looks like following: pgm2asc.o: pgm2asc.c ../include/config.h amiga.h list.h pgm2asc.h pnm.h \ output.h gocr.h unicode.h ocr1.h ocr0.h otsu.h barcode.h progress.h box.o: box.c gocr.h pnm.h ../include/config.h unicode.h list.h pgm2asc.h \ output.h database.o: database.c gocr.h pnm.h ../include/config.h unicode.h list.h \ pgm2asc.h output.h detect.o: detect.c pgm2asc.h pnm.h ../include/config.h output.h gocr.h \ unicode.h list.h I need to catch only C++ header files (i.e. ending with .h), make the list unique and print as space-separated list prepending src/ as a path-prefix. This is achieved by the following perl script: make libs-depends | perl -e 'while (<>) { while (/ ([\w\.\/]+?\.h)/g) { $a{$1} = 1; } } print join " ", map { "src/$_" } keys %a;' The output is: src/unicode.h src/pnm.h src/progress.h src/amiga.h src/ocr0.h src/ocr1.h src/otsu.h src/barcode.h src/gocr.h src/../include/config.h src/list.h src/pgm2asc.h src/output.h Please, help to express this in sed.

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• Shortest Distance From An Array

  - by notyou61

  I have an ajax function which returns the latitudes and longitudes of locations stored in a database. These are returned and placed in an array. A calculation is performed to return their distance from the users current location based on the latitude/longitude. I would like to return only the record with the shortest calculated distance. My code is as follows: Ajax Success // Success success: function (data) { // Obtain Log/Lat navigator.geolocation.getCurrentPosition(function(position) { // Obtain Current Position Lat/Lon glbVar.latitude = position.coords.latitude; glbVar.longitude = position.coords.longitude; // Console Log //console.log('Lat: ' + glbVar.latitude + ' Lon: ' + glbVar.longitude); // Obtain Location Distances for ( var i = 0; i < data.length; i++ ) { // Location Instances var varLocation = data[i]; // Location Distance varLocation.distance = calculateDistance(glbVar.longitude, glbVar.latitude, varLocation.locationLongitude, varLocation.locationLatitude); } // Sort Locations By Distance var sortedData = data.sort(function(a, b) { // Return Locations return a.distance - b.distance; }); // Output Results $.map(sortedData, function(item) { // Obtain Location Distance varLocationsDistance = calculateDistance(glbVar.longitude, glbVar.latitude, item.locationLongitude, item.locationLatitude); // Obtain Location Radius Assignment if (varLocationsDistance <= varLocationRadius) { // Function Return functionReturn = $({locationID : item.locationID + ', Distance : ' + varLocationsDistance + ' m'}); // Return // Function to get the Min value in Array Array.min = function( sortedData ){ functionReturn = Math.min.apply( Math, sortedData ); // console.log(functionReturn); }; } }); }); } The calculateDistance function returns the distance from the users current location and those from the database. The varLocationsDistance <= varLocationRadius "If" statement returns records within a certain distance radius (100 meters), within that statement I would like to return the shortest distance. I am a self taught amateur web developer and as a result may not have provide enough information for an answer, please let me know. Thanks,

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• Error using to_char // to_timetamp

  - by pepersview

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

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• How can I handle all my errors/messages in one place on an Asp.Net page?

  - by Atomiton

  Hi all, I'm looking for some guidance here. On my site I put things in Web user controls. For example, I will have a NewsItem Control, an Article Control, a ContactForm control. These will appear in various places on my site. What I'm looking for is a way for these controls to pass messages up to the Page that they exist on. I don't want to tightly couple them, so I think I will have to do this with Events/Delegates. I'm a little unclear as to how I would implement this, though. A couple of examples: 1 A contact form is submitted. After it's submitted, instead of replacing itself with a "Your mail has been sent" which limits the placement of that message, I'd like to just notify the page that the control is on with a Status message and perhaps a suggested behaviour. So, a message would include the text to render as well as an enum like DisplayAs.Popup or DisplayAs.Success 2 An Article Control queries the database for an Article object. Database returns an Exception. Custom Exception is passed to the page along with the DisplayAs.Error enum. The page handles this error and displays it wherever the errors go. I'm trying to accomplish something similar to the ValidationSummary Control, except that I want the page to be able to display the messages as the enum feels fit. Again, I don't want to tightly bind or rely a control existing on the Page. I want the controls to raise these events, but the page can ignore them if it wants. Am I going about this the right way? I'd love a code sample just to get me started. I know this is a more involved question, so I'll wait longer before voting/choosing the answers.

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• Can g++ fill uninitialized POD variables with known values?

  - by Bob Lied

  I know that Visual Studio under debugging options will fill memory with a known value. Does g++ (any version, but gcc 4.1.2 is most interesting) have any options that would fill an uninitialized local POD structure with recognizable values? struct something{ int a; int b; }; void foo() { something uninitialized; bar(uninitialized.b); } I expect uninitialized.b to be unpredictable randomness; clearly a bug and easily found if optimization and warnings are turned on. But compiled with -g only, no warning. A colleague had a case where code similar to this worked because it coincidentally had a valid value; when the compiler upgraded, it started failing. He thought it was because the new compiler was inserting known values into the structure (much the way that VS fills 0xCC). In my own experience, it was just different random values that didn't happen to be valid. But now I'm curious -- is there any setting of g++ that would make it fill memory that the standard would otherwise say should be uninitialized?

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• The best way to predict performance without actually porting the code?

  - by ardiyu07

  I believe there are people with the same experience with me, where he/she must give a (estimated) performance report of porting a program from sequential to parallel with some designated multicore hardwares, with a very few amount of time given. For instance, if a 10K LoC sequential program was given and executes on Intel i7-3770k (not vectorized) in 100 ms, how long would it take to run if one parallelizes the code to a Tesla C2075 with NVIDIA CUDA, given that all kinds of parallelizing optimization techniques were done? (but you're only given 2-4 days to report the performance? assume that you didn't know the algorithm at all. Or perhaps it'd be safer if we just assume that it's an impossible situation to finish the job) Therefore, I'm wondering, what most likely be the fastest way to give such performance report? Is it safe to calculate solely by the hardware's capability, such as GFLOPs peak and memory bandwidth rate? Is there a mathematical way to calculate it? If there is, please prove your method with the corresponding problem description and the algorithm, and also the target hardwares' specifications. Or perhaps there already exists such tool to (roughly) estimate code porting? (Please don't the answer: 'kill yourself is the fastest way.')

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• How can i get my delete messages function just appear for the user's own messages left on their friends page?

  - by Hannah_B

  I had been working on this trying the delete message button to work on my own profile page of my site. When I delete a message left by a friend it not only deletes it from the screen but deletes it from the database. The messages in the database have 4 fields: message_id, from, to and message. Here is my profile view that shows how Im deleting messages from my friends: if(!empty($messages)){ foreach($messages as $message): $delete = $message['message_id']; //var_dump($message); ?> <li><?=$message['from']?> says...: "<?=$message['message']?>"(<?=anchor("home/deleteMsg/$delete", 'delete')?>)</li> //this is where the delete button appears beside messages left <?php endforeach?> <?php }else{ ?> <?php echo 'No messages left yet !!!'; }?> Here is my controller showing the deleteMsg function called: function deleteMsg($messageid) { $this->messages->deleteMsg($messageid); redirect('home'); } Here is the messages model showing the deleteMsg model itself: function deleteMsg($message_id) { $this->db->where(array('message_id' => $message_id)); $this->db->delete('messages'); } Here is my friendprofile view where I want to implement the delete message command just so the button appears for messages Ive left and I can delete them. The delete button will not appear beside other friends comments on this page: <li><?=$message['from']?> says...: "<?=$message['message']?>"</li> Now I've tried creating a new delete Message function to no success so far, am I better off doing this than calling the same function? As this didnt work either.

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• JPA + EJB + JSF: how can design complicated query

  - by Harry Pham

  I am using netbean 6.8 btw. Let say that I have 4 different tables: Company, Facility, Project, and Document. So the relationship is this. A company can have multiple facilities. A facility can have multiple projects, and a project can have multiple documents. Company: +companyNum: PK +facilityNum: FK Facility: +facilityNum: PK +projectNum: FK Project: +projectNum: PK +drawingNum: FK So when I create Entity Class From Database in netbean 6.8, I have 4 entity classes that named after the above 4 tables. So if I want to see all the Document in the database, then it is easy. In my SessionBean, I would do this: @PersistenceContext private EntityManager em; List<Document> documents = em.createNamedQuery("Document.findAll").getResultList(); However, that is not all what I need. Let say that I want to know all the Document from a particular Company, or all the Document from a particular Project from a particular Facility from a particular Company. I am very new to JPA + EJB + JSF as a whole. Please help me out.

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• NSPredicate always gives back the same data

  - by Stef Geelen

  I am trying to work with NSPredicates. But it always give me back the same array. Here you can see my predicate. NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSPredicate *predicate = [NSPredicate predicateWithFormat:@"whichAlbum.album_id == %d", AlbumId]; [request setEntity:[NSEntityDescription entityForName:@"Picture" inManagedObjectContext:self.genkDatabase.managedObjectContext]]; [request setPredicate:predicate]; Also when I try it hardcoded. It gives back the same array. NSPredicate *predicate = [NSPredicate predicateWithFormat:@"whichAlbum.album_id == 5"]; Here you can see my database model. And here you can see how I put data in my database for entity Picture. + (Picture *)pictureWithGenkInfo:(NSDictionary *)genkInfo inManagedObjectContext:(NSManagedObjectContext *)context withAlbumId:(int)albumId withPictureId:(int)pictureId; { Picture *picture = nil; picture = [NSEntityDescription insertNewObjectForEntityForName:@"Picture" inManagedObjectContext:context]; picture.url = [genkInfo objectForKey:PICTURES_URL]; picture.pic_album_id = [NSNumber numberWithInt:albumId]; picture.picture_id = [NSNumber numberWithInt:pictureId]; return picture; } Anybody can help me ? Kind regards

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