Search Results

Search found 14719 results on 589 pages for 'optimization level'.

Page 515/589 | < Previous Page | 511 512 513 514 515 516 517 518 519 520 521 522  | Next Page >

• Is the 'var' keyword bad? Or am I just old school?

  - by WaggingSiberian

  Recently I overheard junior developer ask "why do you use 'var' so much?". The mid-level developer responded "I use VAR all the time. I love it! I don't have to figure out the type." I didn't have the time or energy to get into a religious war and hey, I'm still the new guy here :-) I understand var has its place. LINQ comes to mind. But I have also always been told the use of var represents lazy programming and I should just use the correct type to begin with. If it's an int, define it as an int, not a var. When reviewing code, seeing the type makes it easier to follow. My opinion is, it's just lazy but there are exceptions. Var also reminds me of the VB/VBA variant type. It also had its place. I recall (from many years ago) its usage being less-than-desirable type and it was rather resource hungry. Am I just being stuck in my ways? Should we start using var all the time as my co-worker does?

  Read the article

• List all foreign key constraints that refer to a particular column in a specific table

  - by Sid

  I would like to see a list of all the tables and columns that refer (either directly or indirectly) a specific column in the 'main' table via a foreign key constraint that has the ON DELETE=CASCADE setting missing. The tricky part is that there would be an indirect relationships buried across up to 5 levels deep. (example: ... great-grandchild- FK3 = grandchild = FK2 = child = FK1 = main table). We need to dig up the leaf tables-columns, not just the very 1st level. The 'good' part about this is that execution speed isn't of concern, it'll be run on a backup copy of the production db to fix any relational issues for the future. I did SELECT * FROM sys.foreign_keys but that gives me the name of the constraint - not the names of the child-parent tables and the columns in the relationship (the juicy bits). Plus the previous designer used short, non-descriptive/random names for the FK constraints, unlike our practice below The way we're adding constraints into SQL Server: ALTER TABLE [dbo].[UserEmailPrefs] WITH CHECK ADD CONSTRAINT [FK_UserEmailPrefs_UserMasterTable_UserId] FOREIGN KEY([UserId]) REFERENCES [dbo].[UserMasterTable] ([UserId]) ON DELETE CASCADE GO ALTER TABLE [dbo].[UserEmailPrefs] CHECK CONSTRAINT [FK_UserEmailPrefs_UserMasterTable_UserId] GO The comments in this SO question inpire this question.

  Read the article

• How to parse mathematical expressions involving parentheses

  - by Rob P.

  Please forgive my title, I really don't know how to phrase it better. This isn't a school assignment or anything, but I realize it's a mostly academic question. But, what I've been struggling to do is parse 'math' text and come up with an answer. For Example - I can figure out how to parse '5 + 5' or '3 * 5' - but I fail when I try to correctly chain operations together. (5 + 5) * 3 It's mostly just bugging me that I can't figure it out. If anyone can point me in a direction, I'd really appreciate it. EDIT Thanks for all of the quick responses. I'm sorry I didn't do a better job of explaining. First - I'm not using regular expressions. I also know there are already libraries available that will take, as a string, a mathematical expression and return the correct value. So, I'm mostly looking at this because, sadly, I don't "get it". Second - What I've tried doing (is probably misguided) but I was counting '(' and ')' and evaluating the deepest items first. In simple examples, this worked; but my code is not pretty and more complicated stuff crashes. When I 'calculated' the lowest level, I was modifying the string. So... (5 + 5) * 3 Would turn into 10 * 3 Which would then evaluate to 30 But it just felt 'wrong'. I hope that helps clarify things. I'll certainly check out the links provided.

  Read the article

• when is a v-table created in C++?

  - by saminny

  When exactly does the compiler create a virtual function table? 1) when the class contains at least one virtual function. OR 2) when the immediate base class contains at least one virtual function. OR 3) when any parent class at any level of the hierarchy contains at least one virtual function. A related question to this: Is it possible to give up dynamic dispatch in a C++ hierarchy? e.g. consider the following example. #include <iostream> using namespace std; class A { public: virtual void f(); }; class B: public A { public: void f(); }; class C: public B { public: void f(); }; Which classes will contain a V-Table? Since B does not declare f() as virtual, does class C get dynamic polymorphism?

  Read the article

• IDENTITY_INSERT ON inside of cursor does not allow inserted id

  - by Mac

  I am trying to set some id's for a bunch of rows in a database where the id column is an identity. I've created a cursor to loop through the rows and update the ids with incrementing negative numbers (-1,-2,-3 etc). When I updated just one row turning on the IDENTITY_INSERT it worked fine but as soon as I try and use it in a cursor, it throws the following error. Msg 8102, Level 16, State 1, Line 22 Cannot update identity column 'myRowID'. DECLARE @MinId INT; SET @MinId = (SELECT MIN(myRowId) FROM myTable)-1; DECLARE myCursor CURSOR FOR SELECT myRowId FROM dbo.myTable WHERE myRowId > 17095 OPEN myCursor DECLARE @myRowId INT FETCH NEXT FROM myCursor INTO @myRowId WHILE (@@FETCH_STATUS <> -1) BEGIN SET IDENTITY_INSERT dbo.myTable ON; --UPDATE dbo.myTable --SET myRowId = @MinId --WHERE myRowId = @myRowId; PRINT (N'ID: ' + CAST(@myRowId AS VARCHAR(10)) + N' NewID: ' + CAST(@MinId AS VARCHAR(4))); SET @MinId = @MinId - 1; FETCH NEXT FROM myCursor INTO @myRowId END CLOSE myCursor DEALLOCATE myCursor GO SET IDENTITY_INSERT dbo.myTable OFF; GO Does anyone know what I'm doing wrong?

  Read the article

• How do I select column(s) by their "numeric" position in a table?

  - by DulcimerDude

  I am trying to select columns by their "x" position in the table. DBI my $example = $hookup->prepare(qq{SELECT This,That,Condition,"I also want COLUMN-10" FROM tbl LIMIT ? ?}); ###column_number=10 ordinal_position?? $example->execute('2','10') or die "Did not execute"; Is this possible or do I need to run another single select to just that column? One problem I encountered was with a col named "Condition". For some reason, when I tried to select Condition the execute would die. I never attempted but, What if the column name was SELECT? Another note is the table is 75 cols wide and I only need 50 of them. The Col names are pretty verbose so, I would like to just call them by their "position". This would also allow the col names to be changed in the future without having to change the select statement. I am quite the newbie so please explain any answers down to my level. Thanks for any assistance..

  Read the article

• jquery .blur for entire block of HTML

  - by Stacey

  I have an HTML item for a 'drop down menu', structured like this... <li class="ui-dropdown-list" > <a href="#">Right Drop Down Menu</a> <ul> <li><a href="#">Item</a></li> <li><a href="#">Item</a></li> <li><a href="#">Item</a></li> </ul> </li> Using jQuery to make this a dropdown list, with the following code. jQuery.fn.dropdown = function () { var defaults = { button: null, menu: null, visible: false }; var options = $.extend(defaults, options); return this.each(function () { options.button = $(this); options.menu = $(this).find("ul"); // when the parent is clicked, determine whether dropdown needs to occur options.button.click(function () { options.visible ? lift(options.menu) : drop(options.menu); options.visible = !options.visible; }); // drop the menu down so that it can be seen. function drop(e) { options.button.addClass("open"); options.menu.show(); } // lift the menu up, hiding it from view. function lift(e) { options.menu.hide(); options.button.removeClass('open'); } }); }; I am trying to wire it up so that if the user clicks anywhere outside of the menu, it will collapse it. This is proving much more difficult than I anticipated; even trying to use page level events. Any suggestions? The menu itself never really 'receives' focus, so using .blur doesn't seem to be suiting the purpose.

  Read the article

• find, excluding dir, not descending into dir, AND using maxdepth and mindepth

  - by user1680819

  This is RHEL 5.6 and GNU find 4.2.27. I am trying to exclude a directory from find, and want to make sure that directory isn't descended into. I've seen plenty of posts saying -prune will do this - and it does. I can run this command: find . -type d -name "./.snapshot*" -prune -o -print and it works. I run it through strace and verify it is NOT descending into .snapshot. I also want to find directories ONLY at a certain level. I can use mindepth and maxdepth to do this: find . -maxdepth 8 -mindepth 8 -type d and it gives me all the dirs 8 levels down, including what's in .snapshot. If I combine the prune and mindepth and maxdepth options: find . -maxdepth 8 -mindepth 8 -type d \( -path "./.snapshot/*" -prune -o -print \) the output is right - I see all the dirs 8 levels down except for what's in .snapshot, but if I run that find through strace, I see that .snapshot is still being descended into - to levels 1 through 8. I've tried a variety of different combinations, moving the precedence parens around, reording expression components - everything that yields the right output still descends into .snapshot. I see in the man page that -prune doesn't work with -depth, but doesn't say anything about mindepth and maxdepth. Can anyone offer any advice? Thanks... Bill

  Read the article

• Logic in the db for maintaining a points system relationship?

  - by MarcusBooster

  I'm making a little web based game and need to determine where to put logic that checks the integrity of some underlying data in the sql database. Each user keeps track of points assigned to him, and points are awarded by various tasks. I keep a record of each task transaction to make sure they're not repeated, and to keep track of the value of the task at the time of completion, since an individual award level my fluctuate over time. My schema looks like this so far: create table player ( player_ID serial primary key, player_Points int not null default 0 ); create table task ( task_ID serial primary key, task_PointsAwarded int not null ); create table task_list ( player_ID int references player(player_ID), task_ID int references task(task_ID), when_completed timestamp default current_timestamp, point_value int not null, --not fk because task value may change later constraint pk_player_task_id primary key (player_ID, task_ID) ); So, the player.player_Points should be the total of all his cumulative task points in the task_list. Now where do I put the logic to enforce this? Should I do away with player.player_Points altogether and do queries every time I want to know the total score? Which seems wasteful since I'll be doing that query a lot over the course of a game. Or, put a trigger in the task_list that automatically updates the player.player_Points? Is that too much logic to have in the database and should just maintain this relationship in the application? Thanks.

  Read the article

• Read all sub directories within a certain folder to display a random image.

  - by Andy

  I have this code i have been using....but i need a conditional where it will read all the sub directories of /bg to select an image as opposed to a specific folder if they were on a subpage. Heres my code so far which works perfectly for all subpages to display specific images: //This would tell us its on the homepage if it helps: $this->level() == 0 //This is the code so far $path = '/home/sites/mydomain.co.uk/public_html/public/images/bg/'.$this->slug; $homepagefile = URL_PUBLIC.'public/images/bg/'.$this->slug.'/main.jpg'; $bgimagearray = array(); $iterator = new DirectoryIterator($path); foreach ($iterator as $fileinfo) { if ($fileinfo->isFile() && !preg_match('\.jpg$/', $fileinfo->getFilename())) { $bgimagearray[] = "'" . $fileinfo->getFilename() . "'"; } } $bgimage = array_rand($bgimagearray); ?> <div id="bg"> <div> <table cellspacing="0" cellpadding="0"> <tr> <td><img src="<?php echo $file.trim($bgimagearray[$bgimage], "'"); ?>" alt=""/></td> </tr> </table> </div> </div> Any help would be appreciated, im sure its not rocket science but ive tried a few ways and cant get my head around it. Thanks in advance.

  Read the article

• HTML5: Rendering absolute images using canvas

  - by Mark

  I am experimenting with canvas as part of my HTML5 introduction. This constitutes as assignment work, but I am not asking for any help on the actual coursework at all. I am trying to write a rendering engine, but having no luck because once the image is drawn on canvas it looks very distorted, and not at the right dimensions of the image itself. I have made a animation engine that loads images into an array, and then iterates through them at a certain speed. This is not the problem, and I assume is not causing the issue as this was happening when I drawn an image to the canvas. I think this is natural behaviour for images to be scaled/skewed when the window is resized, so I conquered that by simply redrawing the whole thing once the window is resized. The images I am using are isometric, and drawn at a pixel level. Would this cause the distortion? It seems setting the dimensions on the drawImage() function are not working are all. I am using JavaScript for the manipulation and rendering of the canvas. I would normally try and work it out myself, but I do not have any time to ponder why because I have no idea why it is even scaling/skewing the image once it is drawn on the canvas. I cannot share the code for obvious reasons. I should also mention, the canvas's dimension is the total width of the viewport, as I am developing a game. My question is: Has anyone encountered this and how would I correct it? Thanks for your help.

  Read the article

• Why is the 'var' keyword bad? Or am I just old school?

  - by WaggingSiberian

  Recently I overheard junior developer ask "why do you use 'var' so much?". The mid-level developer responded "I use VAR all the time. I love it! I don't have to figure out the type." I didn't have the time or energy to get into a religious war and hey, I'm still the new guy here :-) I understand var has its place. LINQ comes to mind. But I have also always been told the use of var represents lazy programming and I should just use the correct type to begin with. If it's an int, define it as an int, not a var. When reviewing code, seeing the type makes it easier to follow. My opinion is, it's just lazy but there are exception. Var also reminds me of the VB/VBA variant type. It also had its place. I recall (from many years ago) its usage being less-than-desirable type and it was rather resource hungry. Am I just being stuck in my ways? Should we start using var all the time as my co-worker does?

  Read the article

• Creating independent process!

  - by Neha

  I am trying to create a process from a service in C++. This new process is creating as a child process. I want to create an independent process and not a child process... I am using CreateProcess function for the same. Since the new process i create is a child process when i try to kill process tree at the service level it is killing the child process too... I dont want this to happen. I want the new process created to run independent of the service. Please advice on the same.. Thanks.. Code STARTUPINFO si; PROCESS_INFORMATION pi; ZeroMemory( &si, sizeof(si) ); si.cb = sizeof(si); // Start the child process. ZeroMemory( &pi, sizeof(pi) ); si.dwFlags = STARTF_USESHOWWINDOW; if(bRunOnWinLogonDesktop) { if(csDesktopName.empty()) si.lpDesktop = _T("winsta0\\default"); else _tcscpy(si.lpDesktop, csDesktopName.c_str()); } if(bHide) si.wShowWindow = SW_HIDE; /* maybe even SW_HIDE */ else si.wShowWindow = SW_SHOW; /* maybe even SW_HIDE */ TCHAR szCmdLine[512]; _tcscpy(szCmdLine, csCmdLine.c_str()); if( !CreateProcess( NULL, szCmdLine, NULL, NULL, FALSE, CREATE_NEW_PROCESS_GROUP, NULL, NULL, &si, &pi ) )

  Read the article

• C# XML Documentation Compiler Warning

  - by ImperialLion

  I am curious as to why I get a compiler warning in the following situation. /// <summary>This is class A /// </summary> public class A { /// <summary>This is the documentation for Method A /// </summary> public void MethodA() { //Do something } } /// <summary>This is class B /// </summary> public class B : A { /// <summary>This does something that I want to /// reference <see cref="MethodA"/> /// </summary> public void MethodB() { //Do something } } The warning states that "XML comment on 'B.MethodB()' has cref attribute 'MethodA' that could not be resolved." If B inherits from A shouldn't the compiler be able to see that method when generating the documentation without me specifying the parent class in the cref? If I change the cref to be cref="A.MethodA()" it works fine, but it seems like that's unnecessary and is a pain to do, especially if I have to go up more than one level. As a note to anyone testing this you have to be sure to "XML documentation file" checked in the Properties - Build in order to see the warning.

  Read the article

• Senior programming 'guru' who can't program - should I find a different career?

  - by confess

  Background: According to my resume I'm supposed to be pretty good at programming. I've worked on a ton of big projects at big companies over many years. When I go for an interview and someone looks at my resume they immediately assume I really know what I'm talking about. I generally communicate well, present myself well, know the 'jargon' and know a lot about technology at a high level, which makes matters worse because after talking to me for a while an interviewer really believes that what my resume says is probably true. The Problem: The problem arises when someone asks me to code something. I choke. As a programmer I have almost no capacity to come up with creative solutions of my own. I can't think through solutions to a programming problem the way good programmers are usually able to. I read questions on StackOverflow and the answer is obvious to me after I read other people's answers but if I am the first person to look at a question with no hints from anyone else I usually don't know where to start. At work it's the same thing. I'm fine if I'm correcting other people's code. I can identify the source of a bug quicker than anyone I work with. But if you ask me to sit down and code up a new application from scratch I will spend ten times longer than programmers who are much more junior than me. Question: Now that I am looking for work this is raising its ugly head in interview situations and making me feel desperately that I'm in the wrong career. I don't know if this problem is incompetence, laziness or some combination of these. Does anyone have any ideas about what I might be dealing with - are there books or exercises that could help me with this basic problem?

  Read the article

• What job title should be most suitable for my object in resume and what salary range should I expect

  - by user354177

  I was a classic asp developer in 2000. After a year of full-time employment, I left the field. I found a part-time position as an asp developer again in 2005 and taught myself vb.net. In 2007, I got the current full-time job as an Asp.net web developer. I taught myself C#, LING t0 SQL, Web Services, AJAX, and creating all kinds of reports with reporting services. One and half years ago, I sent myself to part-time graduate program in Database and Web Systems. I'll have two semesters to go and so far my GPA is 4.0/4.0. My job responsibility is to collect business requirements from other departments, design the database, write stored procedures, create aspx pages, and create reports. I love what I do and want to advance my career to the next level. What I enjoy most is to design the relational database. I would want to become an .Net Architect eventually. I got an interview. They were looking for asp.net web developer. But I was surprised and disappointed that position would only create aspx pages. I would not even have opportunity to write stored procedures, let alone design the database (those would be provided by another group). Furthermore, they asked me some detailed questions about web forms, some of which I did not know the answers. they might be disappointed as well. I am eager to learn and can apply what I learn to real projects right away. I believe no matter what specific skills I am lacking for a new position, I can catch up quickly. I am looking for $70k range job. The object in my resume is Experience C# Web Application Developer. Due to the experience from last interview, I wonder if the object is really what I want. Could somebody answer my questions? Thank you.

  Read the article

• How to document an existing small web site (web application), inside and out?

  - by Ricket

  We have a "web application" which has been developed over the past 7 months. The problem is, it was not really documented. The requirements consisted of a small bulleted list from the initial meeting 7 months ago (it's more of a "goals" statement than software requirements). It has collected a number of features which stemmed from small verbal or chat discussions. The developer is leaving very soon. He wrote the entire thing himself and he knows all of the quirks and underlying rules to each page, but nobody else really knows much more than the user interface side of it; which of course is the easy part, as it's made to be intuitive to the user. But if someone needs to repair or add a feature to it, the entire thing is a black box. The code has some minimal comments, and of course the good thing about web applications is that the address bar points you in the right direction towards fixing a problem or upgrading a page. But how should the developer go about documenting this web application? He is a bit lost as far as where to begin. As developers, how do you completely document your web applications for other developers, maintainers, and administrative-level users? What approach do you use, where do you start, do you have a template? An idea of magnitude: it uses PHP, MySQL and jQuery. It has about 20-30 main (frontend) files, along with about 15 included files and a couple folders of some assets. So overall it's a pretty small application. It interfaces with 7 MySQL tables, each one well-named, so I think the database end is pretty self-explanatory. There is a config.inc.php file with definitions of consts like the MySQL user details, some from/to emails, and URLs which PHP uses to insert into emails and pages (relative and absolute paths, basiecally). There is some AJAX via jQuery. Please comment if there is any other information that would help you help me and I will be glad to edit it in.

  Read the article

• Zend Framework - How do make a hierarchy without it being a module?

  - by Josh

  Here is my specific issue. I want to make an api level which then under that you can select which method you will use. For example: test.com/api/rest test.com/api/xmlprc Currently I have api mapping to a module directory. I then setup a route to make it a rest route. test.com/api is a rest route, but I would rather have it be test.com/api/rest. This would allow me later to add others. In Bootstrap.php: $front = Zend_Controller_Front::getInstance(); $router = $front->getRouter(); $route = new Zend_Controller_Router_Route( 'api/:module/:controller/:id/*', array('module' =>'default') ); $router-addRoute('api', $route); $restRoute = new Zend_Rest_Route($front, array(), array( 'rest' )); $router-addRoute('rest', $restRoute); return $router; In application.ini: resources.frontController.moduleDirectory = APPLICATION_PATH "/modules" I know it will involve routes, but sometimes I find the Zend Framework documentation to be a little hard to follow. When I go to test.com/rest/controller/ it works how it should, but if I go to test.com/api/rest/ it tells me that my module is api and controller is rest.

  Read the article

• How can I call a function in a parent movieclip from an externally-loaded child?

  - by Doug Wolfgram

  I have a swf file that is my 'shell' program that contains many functions. This shell program loads child movies. In the root timeline of the child movie, I have the following code: function putresponse(q,r) { trace (r); _root.debug(r); } _root.debug("foo"); Debug is a function that writes some text to the screen. When I run this locally, the putresponse function gets called and the trace happens. When I run it remotely (inside the shell) the first debug happens immediately on load (as you'd expect) but then later when putresponse is called, the debug(r) is not executed. The external clip is at the same url as the shell so I don't think it is a security issue. Also, as I said, the debug("foo") works fine. This one really has me perplexed. Can anyone shed some light as to why I can't call the debug from _root when called from a function rather than on the first-level timeline? EDIT: The call to putresponse is coming form two layers deep in local (within the child MC) MCs. The actual call is: _parent._parent.putrepsonse(q,r);

  Read the article

• Saving Data to Relational Database (Entity Framework)

  - by sheefy

  I'm having a little bit of trouble saving data to a database. Basically, I have a main table that has associations to other tables (Example Below). Tbl_Listing ID UserID - Associated to ID in User Table CategoryID - Associated to ID in Category Table LevelID - Associated to ID in Level Table. Name Address Normally, it's easy for me to add data to the DB (using Entity Framework). However, I'm not sure how to add data to the fields with associations. The numerous ID fields just need to hold an int value that corresponds with the ID in the associated table. For example; when I try to access the column in the following manner I get a "Object reference not set to an instance of an object." error. Listing NewListing = new Listing(); NewListing.Tbl_User.ID = 1; NewListing.Tbl_Category.ID = 2; ... DBEntities.AddToListingSet(NewListing); DBEntities.SaveChanges(); I am using NewListing.Tbl_User.ID instead of NewListing.UserID because the UserID field is not available through intellisense. If I try and create an object for each related field I get a "The relationship between the two objects cannot be defined because they are attached to different ObjectContext objects." error. With this method, I am trying to add the object without the .ID shown above - example NewListing.User = UserObject. I know this should be simple as I just want to reference the ID from the associated table in the main Listing's table. Any help would be greatly appreciated. Thanks in advance, -S

  Read the article

• How to enforce that HTTP client uses conditional requests for updates?

  - by Day

  In a (proper RMM level 3) RESTful HTTP API, I want to enforce the fact that clients should make conditional requests when updating resources, in order to avoid the lost update problem. What would be an appropriate response to return to clients that incorrectly attempt unconditional PUT requests? I note that the (abandoned?) mod_atom returns a 405 Method Not Allowed with an Allow header set to GET, HEAD (view source) when an unconditional update is attempted. This seems slightly misleading - to me this implies that PUT is never a valid method to attempt on the resource. Perhaps the response just needs to have an entity body explaining that If-Match or If-Unmodified-Since must be used to make the PUT request conditional in which case it would be allowed? Or perhaps a 400 Bad Request with a suitable explanation in the entity body would be a better solution? But again, this doesn't feel quite right because it's using a 400 response for a violation of application specific semantics when RFC 2616 says (my emphasis): The request could not be understood by the server due to malformed syntax. But than again, I think that using 400 Bad Request for application specific semantics is becoming a widely accepted pragmatic solution (citation needed!), and I'm just being overly pedantic.

  Read the article

• Reload a UITable on the fly when editing a UITextField inside one of the cells

  - by Saze

  I have a UITable containing some customs UITableCells. Those cells contain a few UILabels and a UITextField. The datasource of the table comes from a main controller's property. (This controller is also the delegate and the dataSource for the table). Here's a simplified screenshot of the UI: Now, I need to update "on the fly" the content of all the UILabels when the user edits one of the UITextFields. To do so, at the I am listening to the "Editing Changed" event at the UITextField level. This triggers the following action: - (IBAction) editChangeHandler: (id) sender { MyAppDelegate *delegate = [[UIApplication sharedApplication] delegate]; [[delegate.viewController.myDataSourceArray objectAtIndex:self.rowIndex] setANumber: [theTextField.text intValue]]; [delegate.viewController reloadRows]; } The reloadRows method in the viewController is as such: - (void) reloadRows { NSLog(@"called reloadRows"); //perform some calculations on the data source objects here... [theUITable reloadData]; } My problem here is that whenever the user changes the value in the field, the reloadRows method is successfully called, so is apparently the reloadData but it also causes the keyboard to be dismissed. So in the end, the user can only touch one key when editing the TextField before the keyboard is dismissed and the table reloaded. Does anybody knows a solution to this or have experienced the same issue?

  Read the article

• Best practice when removing entity regarding mappedBy collections?

  - by Daniel Bleisteiner

  I'm still kind of undecided which is the best practice to handle em.remove(entity) with this entity being in several collections mapped using mappedBy in JPA. Consider an entity like a Property that references three other entities: a Descriptor, a BusinessObject and a Level entity. The mapping is defined using @ManyToOne in the Property entity and using @OneToMany(mappedBy...) in the other three objects. That inverse mapping is defined because there are some situations where I need to access those collections. Whenever I remove a Property using em.remove(prop) this element is not automatically removed from managed entities of the other three types. If I don't care about that and the following page load (webapp) doesn't reload those entities the Property is still found and some decisions might be taken that are no longer true. The inverse mappings may become quite large and though I don't want to use something like descriptor.getProperties().remove(prop) because it will load all those properties that might have been lazy loaded until then. So my currently preferred way is to refresh the entity if it is managed: if (em.contains(descriptor)) em.refresh(descriptor) - which unloads a possibly loaded collection and triggers a reload upon the next access. Is there another feasible way to handle all those mappedBy collections of already loaded entites?

  Read the article

• [C++] Parent-Child scheme

  - by rubenvb

  I'm writing a class that holds a pointer to a parent object of the same type (think Qt's QObject system). Each object has one parent, and the parent should not be destroyed when a child is destroyed (obviously). class MyClass { public: MyClass(const MyClass* ptr_parent): parent(parent){}; ~MyClass(){ delete[] a_children; }; private: const MyClass* ptr_parent; // go to MyClass above MyClass* a_children; // go to MyClass below size_t sz_numChildren; // for iterating over a_children } (Excuse my inline coding, it's only for brevity) Will destroying the "Master MyClass" take care of all children? No child should be able to kill it's parent, because I would then have pointers in my main program to destroyed objects, correct? Why might you ask? I need a way to "iterate" through all subdirectories and find all files on a platform independent level. The creation of this tree will be handled by native API's, the rest won't. Is this a good idea to start with? Thanks!

  Read the article

• What is a good solution to log the deletion of a row in MySQL?

  - by hobodave

  Background I am currently logging deletion of rows from my tickets table at the application level. When a user deletes a ticket the following SQL is executed: INSERT INTO alert_log (user_id, priority, priorityName, timestamp, message) VALUES (9, 4, 'WARN', NOW(), "TICKET: David A. deleted ticket #6 from Foo"); Please do not offer schema suggestions for the alert_log table. Fields: user_id - User id of the logged in user performing the deletion priority - Always 4 priorityName - Always 'WARN' timestamp - Always NOW() message - Format: "[NAMESPACE]: [FullName] deleted ticket #[TicketId] from [CompanyName]" NAMESPACE - Always TICKET FullName - Full name of user identified by user_id above TicketId - Primary key ID of the ticket being deleted CompanyName - Ticket has a Company via tickets.company_id Situation/Questions Obviously this solution does not work if a ticket is deleted manually from the mysql command line client. However, now I need to. The issues I'm having are as follows: Should I use a PROCEDURE, FUNCTION, or TRIGGER? -- Analysis: TRIGGER - I don't think this will work because I can't pass parameters to it, and it would trigger when my application deleted the row too. PROCEDURE or FUNCTION - Not sure. Should I return the number of deleted rows? If so, that would require a FUNCTION right? How should I account for the absence of a logged in user? -- Possibilities: Using either a PROC or FUNC, require the invoker to pass in a valid user_id Require the user to pass in a string with the name Use the CURRENT_USER - meh Hard code the FullName to just be "Database Administrator" Could the name be an optional parameter? I'm rather green when it comes to sprocs. Assuming I went with the PROC/FUNC approach, is it possible to outright restrict regular DELETE calls to this table, yet still allow users to call this PROC/FUNC to do the deletion for them? Ideally the solution is usable by my application as well, so that my code is DRY.

  Read the article

< Previous Page | 511 512 513 514 515 516 517 518 519 520 521 522  | Next Page >