Search Results

Search found 7324 results on 293 pages for 'operations research'.

Page 235/293 | < Previous Page | 231 232 233 234 235 236 237 238 239 240 241 242  | Next Page >

• Destructors not called when native (C++) exception propagates to CLR component

  - by Phil Nash

  We have a large body of native C++ code, compliled into DLLs. Then we have a couple of dlls containing C++/CLI proxy code to wrap the C++ interfaces. On top of that we have C# code calling into the C++/CLI wrappers. Standard stuff, so far. But we have a lot of cases where native C++ exceptions are allowed to propagate to the .Net world and we rely on .Net's ability to wrap these as System.Exception objects and for the most part this works fine. However we have been finding that destructors of objects in scope at the point of the throw are not being invoked when the exception propagates! After some research we found that this is a fairly well known issue. However the solutions/ workarounds seem less consistent. We did find that if the native code is compiled with /EHa instead of /EHsc the issue disappears (at least in our test case it did). However we would much prefer to use /EHsc as we translate SEH exceptions to C++ exceptions ourselves and we would rather allow the compiler more scope for optimisation. Are there any other workarounds for this issue - other than wrapping every call across the native-managed boundary in a (native) try-catch-throw (in addition to the C++/CLI layer)?

  Read the article

• Architecting ASP.net MVC App to use repositories and services

  - by zaladane

  Hello, I recently started reading about ASP.net MVC and after getting excited about the concept, i started to migrate all my webform project to MVC but i am having a hard time keeping my controller skinny even after following all the good advices out there (or maybe i just don't get it ... ). The website i deal with has Articles, Videos, Quotes ... and each of these entities have categories, comments, images that can be associated with it. I am using Linq to sql for database operations and for each of these Entities, i have a Repository, and for each repository, i create a service to be used in the controller. so i have - ArticleRepository ArticleCategoryRepository ArticleCommentRepository and the corresponding service ArticleService ArticleCategoryService ... you see the picture. The problem i have is that i have one controller for article,category and comment because i thought that having ArticleController handle all of that might make sense, but now i have to pass all of the services needed to the Controller constructor. So i would like to know what it is that i am doing wrong. Are my services not designed properly? should i create Bigger service to encapsulate smaller services and use them in my controller? or should i have an articleCategory Controller and an articleComment Controller? A page viewed by the user is made of all of that, thee article to be viewed,the comments associated with it, a listing of the categories to witch it applies ... how can i efficiently break down the controller to keep it "skinny" and solve my headache? Thank you! I hope my question is not too long to be read ...

  Read the article

• Two way sync with rsync

  - by mwm

  I have a folder a/ and a remote folder A/. I now run something like this on a Makefile: get-music: rsync -avzru server:/media/10001/music/ /media/Incoming/music/ put-music: rsync -avzru /media/Incoming/music/ server:/media/10001/music/ sync-music: get-music put-music when I make sync-music, it first gets all the diffs from server to local and then the opposite, sending all the diffs from local to server. This works very well only if there are just updates or new files on the future. If there are deletions, it doesn't do anything. In rsync there is --delete and --delete-after options to help accomplish what I want but thing is, it doesn't work on a 2-way-sync. If I want to delete server files on a syn, when local files have been deleted, it works, but if, for some reason (explained after) I have some files that aren't in the server but exist locally and they were deleted, I want locally to remove them and not server copied (as it happens). Thing is I have 3 machines in context: desktop notebook home-server So, sometimes, server will have files that were deleted with a notebook sync, for example and then, when I run a sync with my desktop (where the deleted server files still exist on) I want these files to be deleted and not to be copied again to the server. I guess this is only possible with a database and track of operations :P Any simple solutions? Thank you.

  Read the article

• Rolling back file moves, folder deletes and mysql queries

  - by Workoholic

  This has been bugging me all day and there is no end in sight. When the user of my php application adds a new update and something goes wrong, I need to be able to undo a complex batch of mixed commands. They can be mysql update and insert queries, file deletes and folder renaming and creations. I can track the status of all insert commands and undo them if an error is thrown. But how do I do this with the update statements? Is there a smart way (some design pattern?) to keep track of such changes both in the file structure and the database? My database tables are MyISAM. It would be easy to just convert everything to InnoDB, so that I can use transactions. That way I would only have to deal with the file and folder operations. Unfortunately, I cannot assume that all clients have InnoDB support. It would also require me to convert many tables in my database to InnoDB, which I am hesitant to do.

  Read the article

• jqGrid : "All in One" approach width jqGridEdit Class > how to set a composite primary key ?

  - by Qualliarys

  Hello, How to set a composite primary key for a "All in One" approach (grid defined in JS file, and data using jqGridEdit Class in php file) ? Please, for me a composite primary key of a table T, is a elementary primary key that is defined with some fields belong to this table T ! Here is my test, but i get no data and cannot use the CRUD operations : In my JS file i have this lines code: ... colModel":[ {"name":"index","index":"index","label":"index"}, // <= THAT'S JUST THE INDEX OF MY TABLE {"name":"user","index":"user","label":"user","key":true}, // <= A PART OF MY COMPOSITE PRIMARY KEY {"name":"pwd","index":"pwd","label":"pwd","key":true}, // <= A PART OF MY COMPOSITE PRIMARY KEY {"name":"state","index":"state","label":"state","key":true}, // <= A PART OF MY COMPOSITE PRIMARY KEY ... <= AND SO ON "url":"mygrid_crud.php", "datatype":"json", "jsonReader":{repeatitems:false}, "editurl": "mygrid_crud.php", "prmNames":{"id":"index"} // <= WHAT I NEED TO WRITE HERE ??? ... In my php file (mygrid_crud.php) : ... $grid = new jqGridEdit($conn); $query = "SELECT * FROM mytable WHERE user='$user' and pwd='$pwd' and state='$state'..."; // <= SELECT * it's ok or i need to specify all fields i need ? $grid->SelectCommand = $query; $grid->dataType = "json"; $grid->table = 'mytable'; $grid->setPrimaryKeyId('index'); // <= WHAT I NEED TO WRITE HERE ??? ... $grid->editGrid(); Please, say me what is wrong, and how to do to set a composite primary key in this approach !? Thank you so much for tour responses.

  Read the article

• How to deploy a number of disparate project types?

  - by niteice

  This question is similar to http://stackoverflow.com/questions/1900269/whats-the-best-way-to-deploy-an-executable-process-on-a-web-server. The situation is this: I'm developing a product that needs to be deployed to a web server. It consists of 4 website projects, a background service, a couple of command-line tools, and two assemblies shared by all of these components. Now, I also happen to administer the server that this product will be deployed on. So I'm familiar with everything that may need to be done to perform an update: Copy website files Replace the service binary Install updated components in the GAC Configure IIS Update database schema After some research it seems that, to reduce deployment time and to be able to let the other sysadmins handle deployment, I want to deploy all of these as an MSI, except that I don't know a thing about installers. I know VS can generate web deployment projects, but where do I go from there? Being able to simply click Next a few times on an installer is my goal for deploying updates. It would also be nice to modularize it, so for example, I could distribute the four websites among multiple servers and have everything appear as individual components in the installer, and as one entity in Add/Remove Programs. Is all of this too much to ask in a single package?

  Read the article

• How to increase the performance of a loop which runs for every 'n' minutes.

  - by GustlyWind

  Hi Giving small background to my requirement and what i had accomplished so far: There are 18 Scheduler tasks run at regular intervals (least being 30 mins) takes input of nearly 5000 eligible employees run into a static method for iteration and generates a mail content for that employee and mails. An average task takes about 9 min multiplied by 18 will be roughly 162 mins meanwhile there would be next tasks which will be in queue (I assume). So my plan is something like the below loop try { // Handle Arraylist of alerts eligible employees Iterator employee = empIDs.iterator(); while (employee.hasNext()) { ScheduledImplementation.getInstance().sendAlertInfoToEmpForGivenAlertType((Long)employee.next(), configType,schedType); } } catch (Exception vEx) { _log.error("Exception Caught During sending " + configType + " messages:" + configType, vEx); } Since I know how many employees would come to my method I will divide the while loop into two and perform simultaneous operations on two or three employees at a time. Is this possible. Or is there any other ways I can improve the performance. Some of the things I had implemented so far 1.Wherever possible made methods static and variables too Didn't bother to catch exceptions and send back because these are background tasks. (And I assume this improves performance) Get the DB values in one query instead of multiple hits. If am successful in optimizing the while loop I think i can save couple of mins. Thanks

  Read the article

• Getting a handle on GIS math, where do I start?

  - by Joshua

  I am in charge of a program that is used to create a set of nodes and paths for consumption by an autonomous ground vehicle. The program keeps track of the locations of all items in its map by indicating the item's position as being x meters north and y meters east of an origin point of 0,0. In the real world, the vehicle knows the location of the origin's lat and long, as it is determined by a dgps system and is accurate down to a couple centimeters. My program is ignorant of any lat long coordinates. It is one of my goals to modify the program to keep track of lat long coords of items in addition to an origin point and items' x,y position in relation to that origin. At first blush, it seems that I am going to modify the program to allow the lat long coords of the origin to be passed in, and after that I desire that the program will automatically calculate the lat long of every item currently in a map. From what I've researched so far, I believe that I will need to figure out the math behind converting to lat long coords from a UTM like projection where I specify the origin points and meridians etc as opposed to whatever is defined already for UTM. I've come to ask of you GIS programmers, am I on the right track? It seems to me like there is so much to wrap ones head around, and I'm not sure if the answer isn't something as simple as, "oh yea theres a conversion from meters to lat long, here" Currently, due to the nature of DGPS, the system really doesn't need to care about locations more than oh, what... 40 km? radius away from the origin. Given this, and the fact that I need to make sure that the error on my coordinates is not greater than .5 meters, do I need anything more complex than a simple lat/long to meters conversion constant? I'm knee deep in materials here. I could use some pointers about what concepts to research. Thanks much!

  Read the article

• Can I add a condition to CakePHP's update statement?

  - by Don Kirkby

  Since there doesn't seem to be any support for optimistic locking in CakePHP, I'm taking a stab at building a behaviour that implements it. After a little research into behaviours, I think I could run a query in the beforeSave event to check that the version field hasn't changed. However, I'd rather implement the check by changing the update statement's WHERE clause from WHERE id = ? to WHERE id = ? and version = ? This way I don't have to worry about other requests changing the database record between the time I read the version and the time I execute the update. It also means I can do one database call instead of two. I can see that the DboSource.update() method supports conditions, but Model.save() never passes any conditions to it. It seems like I have a couple of options: Do the check in beforeSave() and live with the fact that it's not bulletproof. Hack my local copy of CakePHP to check for a conditions key in the options array of Model.save() and pass it along to the DboSource.update() method. Right now, I'm leaning in favour of the second option, but that means I can't share my behaviour with other users unless they apply my hack to their framework. Have I missed an easier option?

  Read the article

• simplify a preload image function in jQuery

  - by robertdd

  after i spent 2 day searching a preload function in jQueryi with no succes, i manage to do this: after i upload the image on server, in a list i get this: <li id="upimagesDYGONI"> <div class="percentage">100%</div> <div class="uploadifyProgress"> <div align=" center" class="uploadifyProgressBar" id="upimagesDYGONIProgressBar" style="width: 100%;"> <!--Progress Bar--> </div> </div> </li> with this function, i preload the image: $.getlastimage = function(id) { $.getJSON('operations.php', {'operation':'getli', 'id':id,}, function(lastimg){ $("#upimages" + id + " .percentage").text('processing'); $("#upimages" + id).append('<a href=""><img id="' + id + '" src="" alt="" /></a>') .parent().attr({"href":"uploads/"+ lastimg +'?'+ (new Date()).getTime()}); $("#"+id).hide().attr({"src":"uploads/"+ lastimg +'?'+ (new Date()).getTime(), "alt":lastimg}) .load(function() { $(this).show(); $("#upimages" + id + " .percentage").remove(); $("#upimages" + id + " .uploadifyProgress").remove(); }); }); } })(jQuery) and i get this: <li id="upimagesLRBHYN" style="" class=""> <a href="uploads/0002.jpg?1271901177027"> <img alt="0002.jpg" src="uploads/0002.jpg?1271901177028" id="LRBHYN" style="display: block;"> </a> </li> how i can simplify the function? i want to use the full power of jQuery!! any idea?

  Read the article

• How to show the progressbar using threading functionality in win32?

  - by kiddo

  In my application I have a simple module were I will read files for some process that will take few seconds..so I thought of displaying a progress bar(using worker thread) while the files are in progress.I have created a thread (code shown below) and also I designed a dialog window with progress control.I used the function MyThreadFunction below to display the progressbar but it just shows only one time and disappears,I am not sure how to make it work.I tried my best inspite of the fact that I am new to threading.Please help me with this friends. reading files void ReadMyFiles() { for(int i = 0; i < fileCount ; fileCount++) { CWinThread* myThread = AfxBeginThread((AFX_THREADPROC)MyThreadFunction,NULL); tempState = *(checkState + index); if(tempCheckState == NOCHECKBOX) { //my operations } else//CHECKED or UNCHECKED { //myoperation } myThread->PostThreadMessage(WM_QUIT,NULL,NULL); } } thread functions UINT MyThreadFunction(LPARAM lparam) { HWND dialogWnd = CreateWindowEx(0,WC_DIALOG,L"Proccessing...",WS_OVERLAPPEDWINDOW|WS_VISIBLE, 600,300,280,120,NULL,NULL,NULL,NULL); HWND pBarWnd = CreateWindowEx(NULL,PROGRESS_CLASS,NULL,WS_CHILD|WS_VISIBLE|PBS_MARQUEE,40,20,200,20, dialogWnd,(HMENU)IDD_PROGRESS,NULL,NULL); MSG msg; PostMessage( pBarWnd, PBM_SETRANGE, 0, MAKELPARAM( 0, 100 ) ); PostMessage(pBarWnd,PBM_SETPOS,0,0); while(PeekMessage(&msg,NULL,NULL,NULL,PM_NOREMOVE)) { if(msg.message == WM_QUIT) { DestroyWindow(dialogWnd); return 1; } AfxGetThread()->PumpMessage(); Sleep(40); } return 1; }

  Read the article

• SQL Design: representing a default value with overrides?

  - by Mark Harrison

  I need a sparse table which contains a set of "override" values for another table. I also need to specify the default value for the items overridden. For example, if the default value is 17, then foo,bar,baz will have the values 17,21,17: table "things" table "xvalue" name stuff name xval ---- ----- ---- ---- foo ... bar 21 bar ... baz ... If I don't care about a FK from xvalue.name - things.name, I could simply put a "DEFAULT" name: table "xvalue" name xval ---- ---- DEFAULT 17 bar 21 But I like having a FK. I could have a separate default table, but it seems odd to have 2x the number of tables. table "xvalue_default" xval ---- 17 table "xvalue" name xval ---- ---- bar 21 I could have a "defaults table" tablename attributename defaultvalue xvalue xval 17 but then I run into type issues on defaultvalue. My operations guys prefer as compact a representation as possible, so they can most easily see the "diff" or deviations from the default. What's the best way to represent this, including the default value? This will be for Oracle 10.2 if that makes a difference.

  Read the article

• Read Java in as Hex

  - by James

  Hi, I have tried to solve this but I keep coming up with stuff that is no help I'm sure this is easy (when you know how of course ;) ) What I would like to do is read in a file using a byte stream like below: while((read = in.read()) != -1){ //code removed to save space Integer.toHexString(read); System.out.println(read); } When it prints out the Hex to the screen it will print out numbers fine e.g 31 13 12 0 but when it comes to a hex code that should be 01 31 it will print 0 131. I want to read it in to a variable like you would see in a hex editor i.e 00 11 21 31 no single numbers as i need to scan the whole file and look for patterns which I know how to do I'm just stuck on this :/ so in short i need a variabe to contain the two hex characters i.e int temp = 01 not int temp = 0 , I hope this all makes sense, I'm a little confused as it's 3am! If anyone knows how to do this I would be most greatful, p.s thanks for the help in advance this site has saved me loads of research and have learnt a lot! Many thanks.

  Read the article

• ACL architechture for a Software As a service in Sprgin 3.0

  - by geoaxis

  I am making a software as a service using Spring 3.0 (Spring MVC, Spring Security, Spring Roo, Hibernate) I have to come up with a flexible access control list mechanism.I have three different kinds of users System (who can do any thing to the system, includes admin and internal daemons) Operations (who can add and delete users, organizations, and do maintenance work on behalf of users and organizations) End Users (they belong to one or more organization, for each organization, the user can have one or more roles, like being organization admin, or organization read-only member) (role like orgadmin can also add users for that organization) Now my question is, how should i model the entity of User? If I just take the End User, it can belong to one or more organizations, so each user can contain a set of references to its organizations. But how do we model the users role for each organization, So for example User UX belongs to organizations og1, og2 and og3, and for og1 he is both orgadmin, and org-read-only-user, where as for og2 he is only orgadmin and for og3 he is only org-read-only-user I have the possibility of making each user belong to one organization alone, but that's making the system bounded and I don't like that idea (although i would still satisfy the requirement) If you have a better extensible ACL architecture, please suggest it. Since its a software as a service, one would expect that alot of different organizations would be part if the same system. I had one concern that it is not a good idea to keep og1 and og2 data on the same DB (if og1 decides to spawn a 100 reports on the system, og2 should not suffer) But that is some thing advanced for now and is not directly related to ACL but to the physical distribution of data and setup of services based on those ACLs This is a community Wiki question, please correct any thing which you wish to do so. Thanks

  Read the article

• How to handle update events on a ASP.NET GridView?

  - by Bogdan M

  Hello, This may sound silly, but I need to find out how to handle an Update event from a GridView. First of all, I have a DataSet, where there is a typed DataTable with a typed TableAdapter, based on a "select all query", with auto-generated Insert, Update, and Delete methods. Then, in my aspx page, I have an ObjectDataSource related to my typed TableAdapter on Select, Insert, Update and Delete methods. Finnally, I have a GridView bound to this ObjectDataSource, with default Edit, Update and Cancel links. How should I implement the edit functionality? Should I have something like this? protected void GridView_RowEditing(object sender, GridViewEditEventArgs e) { using(MyTableAdapter ta = new MyTableAdapter()) { ta.Update(...); TypedDataTable dt = ta.GetRecords(); this.GridView.DataSource = dt; this.GridView.DataBind(); } } In this scenario, I have the feeling that I update some changes to the DB, then I retrive and bind all the data, and not only the modified parts. Is there any way to update only the DataSet, and this to update on his turn the DataBase and the GridView? I do not want to retrive all the data after a CRUD operations is performed, I just want to retrive the changes made. Thanks. PS: I'm using .NET 3.5 and VS 2008 with SP1.

  Read the article

• Database design MySQL using foreign keys

  - by dscher

  I'm having some a little trouble understanding how to handle the database end of a program I'm making. I'm using an ORM in Kohana, but am hoping that a generalized understanding of how to solve this issue will lead me to an answer with the ORM. I'm writing a program for users to manage their stock research information. My tables are basically like so: CREATE TABLE tags( id INT AUTO_INCREMENT NOT NULL PRIMARY KEY, tags VARCHAR(30), UNIQUE(tags) ) ENGINE=INNODB DEFAULT CHARSET=utf8; CREATE TABLE stock_tags( id INT AUTO_INCREMENT NOT NULL PRIMARY KEY, tag_id INT NOT NULL, stock_id INT NOT NULL, FOREIGN KEY (tag_id) REFERENCES tags(id), FOREIGN KEY(stock_id) REFERENCES stocks(id) ON DELETE CASCADE ) ENGINE=INNODB DEFAULT CHARSET=utf8; CREATE TABLE notes( id INT AUTO_INCREMENT NOT NULL, stock_id INT NOT NULL, notes TEXT NOT NULL, FOREIGN KEY (stock_id) REFERENCES stocks(id) ON DELETE CASCADE, PRIMARY KEY(id) ) ENGINE=INNODB DEFAULT CHARSET=utf8; CREATE TABLE links( id INT AUTO_INCREMENT NOT NULL, stock_id INT NOT NULL, links VARCHAR(2083) NOT NULL, FOREIGN KEY (stock_id) REFERENCES stocks(id) ON DELETE CASCADE, PRIMARY KEY(id) ) ENGINE=INNODB DEFAULT CHARSET=utf8; How would I get all the attributes of a single stock, including its links, notes, and tags? Do I have to add links, notes, and tags columns to the stocks table and then how do you call it? I know this differs using an ORM and I'd assume that I can use join tables in SQL. Thanks for any help, this will really help me understand the issue a lot better.

  Read the article

• POST a form in an iframe.

  - by Stavros Korokithakis

  I would like to POST a form in an iframe, generated like so: My JS loads an iframe inside the page, adds a form to the iframe and submits the form. What I would like to happen is the iframe to load the result of that request. So, I would effectively like to post a form and render the result inside the iframe, without touching the parent (apart from putting the iframe up for display in the first place). I am using the code from this answer: http://stackoverflow.com/questions/133925/javascript-post-request-like-a-form-submit/134003#134003 but I can't get it to not reload the parent. I post the form, and instead of the iframe refreshing, the entire parent refreshes. I don't know why that is, since the url it's posting to is different and would at least redirect there. Can anyone help me with this problem? I just want a post inside an iframe and only within the iframe, basically. EDIT: After some more research, apparently the form is not being created properly. I'm using document.createElement("form") and then document.getElementById("my_iframe_id").appendChild(form) to append it, but it does not seem to be working correctly.

  Read the article

• What does this structure actually do?

  - by LGTrader

  I found this structure code in a Julia Set example from a book on CUDA. I'm a newbie C programmer and cannot get my head around what it's doing, nor have I found the right thing to read on the web to clear it up. Here's the structure: struct cuComplex { float r; float i; cuComplex( float a, float b ) : r(a), i(b) {} float magnitude2( void ) { return r * r + i * i; } cuComplex operator*(const cuComplex& a) { return cuComplex(r*a.r - i*a.i, i*a.r + r*a.i); } cuComplex operator+(const cuComplex& a) { return cuComplex(r+a.r, i+a.i); } }; and it's called very simply like this: cuComplex c(-0.8, 0.156); cuComplex a(jx, jy); int i = 0; for (i=0; i<200; i++) { a = a * a + c; if (a.magnitude2() > 1000) return 0; } return 1; So, the code did what? Defined something of structure type 'cuComplex' giving the real and imaginary parts of a number. (-0.8 & 0.156) What is getting returned? (Or placed in the structure?) How do I work through the logic of the operator stuff in the struct to understand what is actually calculated and held there? I think that it's probably doing recursive calls back into the stucture float magnitude2 (void) { return return r * r + i * i; } probably calls the '*' operator for r and again for i, and then the results of those two operations call the '+' operator? Is this correct and what gets returned at each step? Just plain confused. Thanks!

  Read the article

• Refactoring exercise with generics

  - by Berryl

  I have a variation on a Quantity (Fowler) class that is designed to facilitate conversion between units. The type is declared as: public class QuantityConvertibleUnits<TFactory> where TFactory : ConvertableUnitFactory, new() { ... } In order to do math operations between dissimilar units, I convert the right hand side of the operation to the equivalent Quantity of whatever unit the left hand side is in, and do the math on the amount (which is a double) before creating a new Quantity. Inside the generic Quantity class, I have the following: protected static TQuantity _Add<TQuantity>(TQuantity lhs, TQuantity rhs) where TQuantity : QuantityConvertibleUnits<TFactory>, new() { var toUnit = lhs.ConvertableUnit; var equivalentRhs = _Convert<TQuantity>(rhs.Quantity, toUnit); var newAmount = lhs.Quantity.Amount + equivalentRhs.Quantity.Amount; return _Convert<TQuantity>(new Quantity(newAmount, toUnit.Unit), toUnit); } protected static TQuantity _Subtract<TQuantity>(TQuantity lhs, TQuantity rhs) where TQuantity : QuantityConvertibleUnits<TFactory>, new() { var toUnit = lhs.ConvertableUnit; var equivalentRhs = _Convert<TQuantity>(rhs.Quantity, toUnit); var newAmount = lhs.Quantity.Amount - equivalentRhs.Quantity.Amount; return _Convert<TQuantity>(new Quantity(newAmount, toUnit.Unit), toUnit); } ... same for multiply and also divide I need to get the typing right for a concrete Quantity, so an example of an add op looks like: public static ImperialLengthQuantity operator +(ImperialLengthQuantity lhs, ImperialLengthQuantity rhs) { return _Add(lhs, rhs); } The question is those verbose methods in the Quantity class. The only change between the code is the math operator (+, -, *, etc.) so it seems that there should be a way to refactor them into a common method, but I am just not seeing it. How can I refactor that code? Cheers, Berryl

  Read the article

• Representing complex scheduled reoccurance in a database

  - by David Pfeffer

  I have the interesting problem of representing complex schedule data in a database. As a guideline, I need to be able to represent the entirety of what the iCalendar -- ics -- format can represent, but in a database. I'm not actually implementing anything relating to ics, but it gives a good scope of the type of rules I need to be able to model. I need to allow allow representation of a single event or a reoccurring event based on multiple times per day, days of the week, week of a month, month, year, or some combination of those. For example, the third Thursday in November annually, or the 25th of December annually, or every two weeks starting November 2 and continuing until September 8 the following year. I don't care about insertion efficiency but query efficiency is critical. The operation I will be doing most often is providing either a single date/time or a date/time range, and trying to determine if the defined schedule matches any part of the date/time range. Other operations can be slower. For example, given January 15, 2010 at 10:00 AM through January 15, 2010 at 11:00 AM, find all schedules that match at least part of that time. (i.e. a schedule that covers 10:30 - 11:00 still matches.) Any suggestions? I looked at http://stackoverflow.com/questions/1016170/how-would-one-represent-scheduled-events-in-an-rdbms but it doesn't cover the scope of the type of reoccurance rules I'd like to model.

  Read the article

• How can I provide users with the functionality of the DBUnit DatabaseOperation methods from a web in

  - by reckoner

  I am currently updating a java-based web application which allows database developers to create stored procedure regression test suites for database testing. Currently, for test setup, execution and clean-up stages, the user is provided with text boxes where they are able to enter SQL code which is executed by the isql command. I would like to extend the application to use DB Unit’s DatabaseOperation methods to provide more ways to setup the state of the database than just SQL statements. The main reason for using Db Unit rather than just SQL statements is to be able to create and store xml and xls DataSets on a server where they can be associated with their test cases and used for data setup. My question is: How can I provide users with the functionality of the DBUnit DatabaseOperation methods from a web interface? I have considered: Creating a simple programming language and a parser to read some simple syntax involving the DB Unit method names which accept a parameter being the file location to an xml or xls DataSet. I was thinking of allowing the user to register the files they need with the web app which would catalogue them and provide each file with an identifier which could passed as a parameter to the methods in this simple programming language. Creating an XML DTD which provides the user with the ability to specify operations and parameters. If I went this approach, how can I execute the methods and their parameters that I parse from the XML document? Creating a table in the database which stores the method and a FK relation to a catalogued DataSet file, however I don’t think this would be good solution due to the fact that data entry would be tedious. Thanks for your help.

  Read the article

• .Net long-running scheduled code execution

  - by Prof Plum

  I am working on a couple of projects now where I really wish there was some sort of component that I could specify a time and date, and then execute some sort of method. DateTime date = new DateTime(x,x,x,x,x,x); ScheduledMethod sMethod = new ScheduledMethod(date, [method delegate of some sort]); \\at the specified date, sMethod invokes [method delegate of some sort] I know that I can do this with Windows Workflow Foundation as a long running process, which is good for certain things, but are there any alternatives? Workflow is not exactly straight forward with the details, and it would be nice to be able to deploy something more simple for light weight tasks. An example would be a method that checks a network folder once a day and deletes any files that are more than 30 days old. I realize that this may be pie in the sky dreaming, but this would be extremely useful for automating certain mundane maintinence tasks (scheduled sql operations, file system cleansing, routine email sending, etc.). It does not necessarily have to be .Net, but that is where I am coming from. Any ideas?

  Read the article

• Grails , how do I get an object NOT to save

  - by user350325

  Hello I am new to grails and trying to create a form which allows a user to change the email address associated with his/her account for a site I am creating. It asks for the user for their current password and also for the new email address they want to use. If the user enters the wrong password or an invalid email address then it should reject them with an appropriate error message. Now the email validation can be done through constraints in grails, but the password change has to match their current password. I have implemented this check as a method on a service class. See code below: def saveEmail = { def client = ClientUser.get(session.clientUserID) client.email = params.email if(clientUserService.checkPassword(session.clientUserID , params.password) ==false) { flash.message = "Incorrect Password" client.discard() redirect(action:'changeEmail') } else if(!client.validate()) { flash.message = "Invalid Email Address" redirect(action:'changeEmail') } else { client.save(); session.clientUserID = null; flash.message = "Your email address has been changed, please login again" redirect(controller: 'clientLogin' , action:'index') } } Now what I noticed that was odd was that if I entered an invalid email then it would not save the changes (as expected) BUT if I entered the wrong password and a valid email then it would save the changes and even write them back into the database even though it would give the correct "invalid password" error message. I was puzzled so set break points in all the if/else if/else blocks and found that it was hitting the first if statement as expected and not hitting the others , so it would never come accross a call to the save() method, yet it was saved anyway. After a little research I came accross documentation for the discard() method which you can see used in the code above. So I added this but still no avail. I even tried using discard then reloading the client object from the DB again but still no dice. This is very frustrating and I would be grateful for any help, since I think that this should surely not be a complicated requirement!

  Read the article

• .NET multithreading, volatile and memory model

  - by fedor-serdukov

  Assume that we have the following code: class Program { static volatile bool flag1; static volatile bool flag2; static volatile int val; static void Main(string[] args) { for (int i = 0; i < 10000 * 10000; i++) { if (i % 500000 == 0) { Console.WriteLine("{0:#,0}",i); } flag1 = false; flag2 = false; val = 0; Parallel.Invoke(A1, A2); if (val == 0) throw new Exception(string.Format("{0:#,0}: {1}, {2}", i, flag1, flag2)); } } static void A1() { flag2 = true; if (flag1) val = 1; } static void A2() { flag1 = true; if (flag2) val = 2; } } } It's fault! The main quastion is Why... I suppose that CPU reorder operations with flag1 = true; and if(flag2) statement, but variables flag1 and flag2 marked as volatile fields...

  Read the article

• CakePHP: Missing database table

  - by Justin

  I have a CakePHP application that is running fine locally. I uploaded it to a production server and the first page that uses a database connection gives the "Missing Database Table" error. When I look at the controller dump, it's complaining about the first table. I've tried a variety of things to fix this problem, with no luck: I've confirmed that at the command line I can login with the given MySQL credentials in database.php I've confirmed this table exists I've tried using the MySQL root credentials (temporarily) to see if the problem lies with permissions of the user. The same error appeared. My debug level is currently set to 3 I've deleted the entire contents of /app/tmp/cache I've set 777 permissions on /app/tmp* I've confirmed that I can run DESCRIBE commands at the commant line MySQL when logged in with the MySQL credentials used by by the application I've verified that the CakePHP log file only contains the error I'm setting in the browser window. I've tried all the suggestions I could find in similar postings on SO I've Googled around and didn't find any other ideas I think I've eliminating the obvious problems and my research isn't turning anything up. I feel like I'm missing something obvious. Any ideas?

  Read the article

< Previous Page | 231 232 233 234 235 236 237 238 239 240 241 242  | Next Page >