Search Results

Search found 12511 results on 501 pages for 'itunes store'.

Page 439/501 | < Previous Page | 435 436 437 438 439 440 441 442 443 444 445 446  | Next Page >

• Does IE completely ignore cache control headers for AJAX requests?

  - by Joshua Hayworth

  Hello there, I've got, what I would consider, a simple test web site. A single page with a single button. Here is a copy of the source I'm working with if you would like to download it and play with it. When that button is clicked, it creates a JavaScript timer that executes once a second. When the timer function is executed, An AJAX call is made to retrieve a text value. That text value is then placed into the DOM. What's my problem? IE Caching. Crack open Task Manager and watch what happens to the iexplorer.exe process (IE 8.0.7600.16385 for me) while the timer in that page is executing. See the memory and handle count getting larger? Why is that happening when, by all accounts, I have caching turned off. I've got the jQuery cache option set to false in $.ajaxSetup. I've got the CacheControl header set to no-cache and no-store. The Expires header is set to DateTime.Now.AddDays(-1). The headers are set in both the page code-behind as well as the HTTP Handler's response. Anybody got any ideas as to how I could prevent IE from caching the results of the AJAX call? Here is what the iexplorer.exe process looks like in ProcessMonitor. I believe that the activity shown in this picture is exactly what I'm attempting to prevent.

  Read the article

• How can I retain the data stored in plist from UITextField when application is restarted ?

  - by srikanth rongali

  I am using the plist to store the data entered in the UITextFields. But, when I restart my application all the data entered previously was deleted. How can I retain the data in the Plist. I have a UITableView and when a cell is touched a view appears with two UITextFields. nameField and descriptionField. I stored the data in this way. My code is. -(void)save:(id)sender { indexOfDataArray = temp; //the cell selected in table view. NSString *string1 = [[NSString alloc]init]; NSString *string2 = [[NSString alloc]init]; string1 = nameField.text; string2 = descriptionField.text; NSDictionary *myDict = [[NSDictionary alloc] initWithObjectsAndKeys:string2, string1, nil]; [myArray addObject:myDict]; //myArray is NSMutableArray declared in tableViewController class. //[myArray insertObject:myDict atIndex:indexOfDataArray]; NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; NSString *path = [documentsDirectory stringByAppendingPathComponent:@"tableVideoData.plist"]; [myArray writeToFile:path atomically:YES]; UIAlertView *alertMesage = [[UIAlertView alloc] initWithTitle: @"Save Alert" message:@"The data entered is saved" delegate:nil cancelButtonTitle:@"cancel" otherButtonTitles:nil] ; [alertMesage show]; [alertMesage release]; } When I am using the [myArray insertObject:myDict atIndex:indexOfDataArray]; It is giving the error *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[NSCFArray insertObject:atIndex:]: index (2) beyond bounds (1)' So I used [myArray addObject:myDict]; Please help me, how can I retain the data in plist. Thank You.

  Read the article

• If Statements Skipping or Evaluating Strangely, JavaScript and jquery

  - by tlm2021

  So in jQuery, I have a global variable "currentSubNav" that stores a current visible element. The following code executes on "mouseenter". I need it to get store element's ID, check to see if there was one. If there wasn't, set the new visible element to the default. $('#mainMenu a').mouseenter(function() { var newName = $(this).attr("id"); if(newName == ''){ var newName = "default"; } Then it checks to see if the new element matches the current one. If so, it returns. If not, it performs the animations to bring in the new one. if(newName == currentSubNav){ return; }else{ $("div[name=" + currentSubNav + "]").animate({"left": "+=600px", "opacity": "toggle"}, "slow"); $("div[name=" + newName + "]").css({"margin-top": "0"}); $("div[name=" + newName + "]").fadeIn(2000); $("div[name=" + currentSubNav + "]").animate({"left": "-=600px"}, 0); currentSubNav = newName; return; } }); I'm using Chrome at the moment, and according to the dev tools that isn't what happens. Problem #1 "$(this).attr("id");" isn't returning undefined as the documentation claims. It seems to be returning "". BUT, when I have the if statement as I do above, it skips over the statement entirely. I set a breakpoint, but it never pauses execuation, so the statement is never evaluated. Problem #2 After the animations occur, instead of using the return at the end of the statements it goes back and uses the return for the "newName == currentSubNav" if statement. I guess that not a big deal, but it's not the intended behavior. I'm fairly new to JavaScript, and it appears I'm missing something about how JavaScript works. But I can't find what anywhere. Any help? Blockquote

  Read the article

• Trying to create a group of button sprites

  - by user1449653

  Good day, I have like 15 images I need to be buttons. I have buttons working with a Box() (Box - looks like this) class Box(pygame.sprite.Sprite): def __init__(self): pygame.sprite.Sprite.__init__(self) self.image = pygame.Surface((35, 30)) self.image = self.image.convert() self.image.fill((255, 0, 0)) self.rect = self.image.get_rect() self.rect.centerx = 25 self.rect.centery = 505 self.dx = 10 self.dy = 10 I am trying to make the buttons work with image sprites. So I attempted to copy the class style of the box and do the same for my Icons.. code looks like this... class Icons(pygame.sprite.Sprite): def __init__(self): pygame.sprite.Sprite.__init__(self) self.image = pygame.image.load("images/airbrushIC.gif").convert() self.rect = self.image.get_rect() self.rect.x = 25 self.rect.y = 550 the code in the main() rect = image.get_rect() rect.x = 25 rect.y = 550 ic1 = Icons((screen.get_rect().x, screen.get_rect().y)) screen.blit(ic1.image, ic1.rect) pygame.display.update() This code produces a positional (accepts 1 argument but 2 are there) error or an image is not referenced error (inside the Icon class). I'm unsure if this is the right way to go about this anyways.. I know for sure that I need to load all the images (as sprites)... store them in an array... and then have my mouse check if it is clicking one of the items in the array using a for loop. Thanks. EDIT QUESTION 2: class Icons(pygame.sprite.Sprite): def init(self, *args): pygame.sprite.Sprite.init(self, *args) self.image = pygame.image.load("images/airbrushIC.gif").convert() self.rect = self.image.get_rect() ic1 = self.image self.rect.x = 10 self.rect.y = 490 self.image = pygame.image.load("images/fillIC.gif").convert() self.rect = self.image.get_rect() ic2 = self.image self.rect.x = 10 self.rect.y = 540 Thanks to your help I got the Icons class loading ONE image. Its not loading both. Obviously because its being overwritten by the second one. It seems that "class" for this purpose isn't what I need. Which begs the question how I make sprites outside of a class.. If there is a way to make the class work please let me know.

  Read the article

• What's the best way to handle layout issues with multi-language support in WPF/XAML?

  - by Tim

  I'm creating a standalone WPF app with multi-language support. I've found some great resources (mostly on SO) on how to store and access the strings as needed. This part is pretty straightforward and doable, but I'm fuzzy on how to take care of screen layout issues. I'm using some custom images to skin up my app for buttons, etc. For instance, here's a button with some text within: <Button Canvas.Left="33" Canvas.Top="484" Style="{StaticResource SmallButtonBase}"> <TextBlock FontSize="20" FontWeight="Bold" TextAlignment="Center" FontFamily="Helvetica"> Enter </TextBlock> </Button> Now here is the same button with text from another language: <Button Canvas.Left="33" Canvas.Top="484" Style="{StaticResource SmallButtonBase}"> <TextBlock FontSize="20" FontWeight="Bold" TextAlignment="Center" FontFamily="Helvetica"> Enterenschtein </TextBlock> </Button> So my question is: What is a good method to prevent this "overflow" situation. I'd like to have XAML take care of any font resizing or indenting that is needed automatically so that I don't have to tweak the UI for each language I'm supporting. Any insight is appreciated!

  Read the article

• Assigning a value to an integer in a C linked list

  - by Drunk On Java

  Hello all. I have a question regarding linked lists. I have the following structs and function for example. struct node { int value; struct node *next; }; struct entrynode { struct node *first; struct node *last; int length; }; void addnode(struct entrynode *entry) { struct node *nextnode = (struct node *)malloc(sizeof(struct node)); int temp; if(entry->first == NULL) { printf("Please enter an integer.\n"); scanf("%d", &temp); nextnode->value = temp; nextnode->next = NULL; entry->first = nextnode; entry->last = nextnode; entry->length++; } else { entry->last->next = nextnode; printf("Please enter an integer.\n"); scanf("%d", nextnode->value); nextnode->next = NULL; entry->last = nextnode; entry->length++; } } In the first part of the if statement, I store input into a temp variable and then assign that to a field in the struct. The else branch, I tried to assign it directly which did not work. How would I go about assigning it directly? Thanks for your time.

  Read the article

• Displaying a message after adding duplicate records in database

  - by user1770370

  I wrote program in C# winforms and SQL server and LINQ to SQL. I use user control instead of form. In my user control, I put 3 textbox, txtStartNumber, txtEndNumber, txtQuantity. user define value of textboxes, when clicked button, it will insert some records according to the value of txtQuantity. I want to when duplicate number is created, it won't add to database and display message. how do i do? I must write code in code behind or server side? i must set this in store procedure or trigger? private void btnSave_Click(object sender, EventArgs e) { long from = Convert.ToInt64(txt_barcode_f.Text); long to = Convert.ToInt64(txt_barcode_t.Text); long quantity = Convert.ToInt64(to - from); int card_Type_ID=Convert.ToInt32(cmb_BracodeType .SelectedValue); long[] arrCardNum = new long[(to - from)]; arrCardNum[0]=from; for (long i = from; i < to; i++) { for(int j=0; j<(to-from) ;j++) { arrCardNum[j]=from+j; string r = arrCardNum[j].ToString(); sp.SaveCards(r, 2, card_Type_ID, SaveDate, 2); } } } Stored Procedure code. ALTER PROCEDURE dbo.SaveCards @Barcode_Num int ,@Card_Status_ID int ,@Card_Type_ID int ,@SaveDate varchar(10) ,@Save_User_ID int AS BEGIN INSERT INTO [Parking].[dbo].[TBL_Cards] ([Barcode_Num] ,[Card_Status_ID] ,[Card_Type_ID] ,[Save_User_ID]) VALUES (@Barcode_Num ,@Card_Status_ID ,@Card_Type_ID ,@Save_User_ID) END

  Read the article

• Best approach to cache Counts from SQL tables ?

  - by pixel3cs

  I would like to develop a Forum from scratch, with special needs and customization. I would like to prepare my forum for intensive usage and wondering how to cache things like User posts count and User replies count. Having only three tables, tblForum, tblForumTopics, tblForumReplies, what is the best approach of cache the User topics and replies counts ? Think at a simple scenario: user press a link and open the Replies.aspx?id=x&page=y page, and start reading replies. On the HTTP Request, the server will run an SQL command wich will fetch all replies for that page, also "inner joining with tblForumReplies to find out the number of User replies for each user that replied." select tblForumReplies.*, tblFR.TotalReplies from tblForumReplies inner join ( select IdRepliedBy, count(*) as TotalReplies from tblForumReplies group by IdRepliedBy ) as tblFR on tblFR.IdRepliedBy = tblForumReplies.IdRepliedBy Unfortunately this approach is very cpu intensive, and I would like to see your ideas of how to cache things like table Counts. If counting replies for each user on insert/delete, and store it in a separate field, how to syncronize with manual data changing. Suppose I will manually delete Replies from SQL.

  Read the article

• wx_ref and custom wx_object's

  - by Iogann

  Hi! I am developing MDI application with help of wxErlang. I have a parent frame, implemented as wx_object: -module(main_frame). -export([new/0, init/1, handle_call/3, handle_event/2, terminate/2]). -behaviour(wx_object). .... And I have a child frame, implemented as wx_object too: module(child_frame). -export([new/2, init/1, handle_call/3, handle_event/2, terminate/2]). -export([save/1]). -behaviour(wx_object). % some public API method save(Frame) -> wx_object:call(Frame, save). .... I want to call save/1 for an active child frame from the parent frame. There is my code: ActiveChild = wxMDIParentFrame:getActiveChild(Frame), case wx:is_null(ActiveChild) of false - child_frame:save(ActiveChild); _ - ignore end This code fails because ActiveChild is #wx_ref{} with state=[], but wx_object:call/2 needs #wx_ref{} where state is set to the pid of the process which we call. What is the right method to do this? I thought only to store a list of all created child frames with its pids in the parent frame and search the pid in this list, but this is ugly.

  Read the article

• how to call array values based on the main id they linked to?

  - by veronica george

  In page one, $add_id2=implode(',',$add_id); //result is 1,4 $item_type2=implode(',',$item_type_2); //result is 8,16 $final_total2=implode(',',$final); //result is 150,430 I pass these values via URL to the page two and store them in session. $_SESSION['cart'][$car]= array ('car'=>$car, 'loc_1'=>$location, array ( 'addon_id'=>$a_id, 'item_type'=>$item_type2, 'final_total'=>$final_t ) ); I call them like this, foreach($_SESSION['cart'] as $cart=>$things) { //display main array value like car id and location id echo $cart; foreach($things as $thing_1=>$thing_2) { foreach($thing_2['addon_id'] as $thi_2=>$thi_4) { //to display addons item for the car id //this is the id for each addon under the above car //echo $thi_2; //this is to echo addon id $thi_4; } } } The above loop works . the addon items array loops through inside main array which is car. If there were two addon items chosen then the addon array will loop twice. Now al I need to do is, How to make $item_type2 and $final_total2 display the value according to the addon id? PS: Same addon items can be chosen multiple times. They are identified uniquely by id(//echo $thi_2;). Thanks.

  Read the article

• R Random Data Sets within loops

  - by jugossery

  Here is what I want to do: I have a time series data frame with let us say 100 time-series of length 600 - each in one column of the data frame. I want to pick up 4 of the time-series randomly and then assign them random weights that sum up to one (ie 0.1, 0.5, 0.3, 0.1). Using those I want to compute the mean of the sum of the 4 weighted time series variables (e.g. convex combination). I want to do this let us say 100k times and store each result in the form ts1.name, ts2.name, ts3.name, ts4.name, weight1, weight2, weight3, weight4, mean so that I get a 9*100k df. I tried some things already but R is very bad with loops and I know vector oriented solutions are better because of R design. Thanks Here is what I did and I know it is horrible The df is in the form v1,v2,v2.....v100 1,5,6,.......9 2,4,6,.......10 3,5,8,.......6 2,2,8,.......2 etc e=NULL for (x in 1:100000) { s=sample(1:100,4)#pick 4 variables randomly a=sample(seq(0,1,0.01),1) b=sample(seq(0,1-a,0.01),1) c=sample(seq(0,(1-a-b),0.01),1) d=1-a-b-c e=c(a,b,c,d)#4 random weights average=mean(timeseries.df[,s]%*%t(e)) e=rbind(e,s,average)#in the end i get the 9*100k df } The procedure runs way to slow. EDIT: Thanks for the help i had,i am not used to think R and i am not very used to translate every problem into a matrix algebra equation which is what you need in R. Then the problem becomes a little bit complex if i want to calculate the standard deviation. i need the covariance matrix and i am not sure i can if/how i can pick random elements for each sample from the original timeseries.df covariance matrix then compute the sample variance (t(sampleweights)%*%sample_cov.mat%*%sampleweights) to get in the end the ts.weighted_standard_dev matrix Last question what is the best way to proceed if i want to bootstrap the original df x times and then apply the same computations to test the robustness of my datas thanks

  Read the article

• How to iterate & retrieve values from NSArray of NSArrays of NSDictionaries

  - by chinjazz

  I'm stumpped on how iterate and get values for an Array of Arrays of NSDictionaries (different classes/entities). Here's what I'm currently doing: 1) Constructing two separate arrays of NSDictionaries (different entities) 2) Combining both arrays with: NSMutableArray *combinedArrayofDicts = [[NSMutableArray alloc] initWithObjects: sizesArrayOfDicts, wishListArrayOfDicts , nil]; 3) Then archive combinedArrayofDicts : NSData *dataToSend = [NSKeyedArchiver archivedDataWithRootObject:combinedArrayofDicts]; 4) Transmit over GameKit [self.session sendDataToAllPiers:dataToSend withDataMode: GKSendDataReliable error:nil]; 5) How would I manage traversing thru this array on the receiving end? I want to fetch values by for each class which is key'ed by classname: Here's how it looks via NSLog (2 Sizes Dicts, and 1 Wishlist Dict) Printing description of receivedArray: <__NSArrayM 0xbc65eb0>( <__NSArrayM 0xbc651f0>( { classname = Sizes; displayOrder = 0; share = 1; sizeType = Neck; value = "13\" or 33 (cm)"; }, { classname = Sizes; displayOrder = 0; share = 1; sizeType = Sleeve; value = "34\" or 86 (cm)"; } ) , <__NSArrayM 0xbc65e80>( { classname = Wishlist; detail = ""; displayOrder = 0; imageString = ""; latitude = "30.33216666666667"; link = "http://maps.google.com/maps?q=loc:30.332,-81.41"; longitude = "-81.40949999999999"; name = bass; share = 1; store = ""; } ) ) (lldb) In my for loop I'm issuing this: NSString *value = [dict objectForKey:@"classname"]; and get an exception: * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayM objectForKey:]: unrecognized selector sent to instance 0xbc651f0' Is this frowned upon as far as mixing object types in arrays of arrays?

  Read the article

• Quickest way to compare a buch of array or list of values.

  - by zapping

  Can you please let me know on the quickest and efficient way to compare a large set of values. Its like there are a list of parent codes(string) and each code has a series of child values(string). The child lists have to be compared with each other and find out duplicates and count how many times they repeat. code1(code1_value1, code1_value2, code3_value3, ..., code1_valueN); code2(code2_value1, code1_value2, code2_value3, ..., code2_valueN); code3(code2_value1, code3_value2, code3_value3, ..., code3_valueN); . . . codeN(codeN_value1, codeN_value2, codeN_value3, ..., codeN_valueN); The lists are huge say like there are 100 parent codes and each has about 250 values in them. There will not be duplicates within a code list. Doing it in java and the solution i could figure out is. Store the values of first set of code in as codeMap.put(codeValue, duplicateCount). The count initialized to 0. Then compare the rest of the values with this. If its in the map then increment the count otherwise append it to the map. The downfall of this is to get the duplicates. Another iteration needs to be performed on a very large list. An alternative is to maintain another hashmap for duplicates like duplicateCodeMap.put(codeValue, duplicateCount) and change the initial hashmap to codeMap.put(codeValue, codeValue). Speed is what is requirement. Hope one of you can help me with it.

  Read the article

• Web services or shared database for (game) server communication?

  - by jaaronfarr

  We have 2 server clusters: the first is made up of typical web applications backed by SQL databases. The second are highly optimized multiplayer game servers which keep all data in memory. Both clusters communicate with clients via HTTP (Ajax with JSON). There are a few cases in which we need to share data between the two server types, for example, reporting back and storing the results of a game (should ultimately end up in the database). We're considering several approaches for inter-server communication: Just share the MySQL databases between clusters (introduce SQL to the game servers) Sharing data in a distributed key-value store like Memcache, Redis, etc. Use an RPC technology like Google ProtoBufs or Apache Thrift Using RESTful web services (the game server would POST back to the web servers, for example) At the moment, we're leaning towards web services or just sharing the database. Sharing the database seems easy, but we're concerned this adds extra memory and a new dependency into the game servers. Web services provide good separation of concerns and fit with the existing Ajax we use, but add complexity, overhead and many more ways for communication to fail. Are there any other good reasons not to use one or the other approach? Which would be easier to scale?

  Read the article

• Storing Number in an integer from sql Database

  - by ar31an

  i am using database with table RESUME and column PageIndex in it which type is number in database but when i want to store this PageIndex value to an integer i get exception error Specified cast is not valid. here is the code string sql; string conString = "Provider=Microsoft.ACE.OLEDB.12.0; Data Source=D:\\Deliverable4.accdb"; protected OleDbConnection rMSConnection; protected OleDbDataAdapter rMSDataAdapter; protected DataSet dataSet; protected DataTable dataTable; protected DataRow dataRow; on Button Click sql = "select PageIndex from RESUME"; rMSConnection = new OleDbConnection(conString); rMSDataAdapter = new OleDbDataAdapter(sql, rMSConnection); dataSet = new DataSet("pInDex"); rMSDataAdapter.Fill(dataSet, "RESUME"); dataTable = dataSet.Tables["RESUME"]; int pIndex = (int)dataTable.Rows[0][0]; rMSConnection.Close(); if (pIndex == 0) { Response.Redirect("Create Resume-1.aspx"); } else if (pIndex == 1) { Response.Redirect("Create Resume-2.aspx"); } else if (pIndex == 2) { Response.Redirect("Create Resume-3.aspx"); } } i am getting error in this line int pIndex = (int)dataTable.Rows[0][0];

  Read the article

• Is Storing Cookies in a Database Safe?

  - by viatropos

  If I use mechanize, I can, for instance, create a new google analytics profile for a website. I do this by programmatically filling out the login form and storing the cookies in the database. Then, for at least until the cookie expires, I can access my analytics admin panel without having to enter my username and password again. Assuming you can't create a new analytics profile any other way (with OpenAuth or any of that, I don't think it works for actually creating a new Google Analytics profile, the Analytics API is for viewing the data, but I need to create an new analytics profile), is storing the cookie in the database a bad thing? If I do store the cookie in the database, it makes it super easy to programatically login to Google Analytics without the user ever having to go to the browser (maybe the app has functionality that says "user, you can schedule a hook that creates a new anaytics profile for each new domain you create, just enter your credentials once and we'll keep you logged in and safe"). Otherwise I have to keep transferring around emails and passwords which seems worse. So is storing cookies in the database safe?

  Read the article

• Database/Object Mapping

  - by Eric

  Hello everyone, This is a beginner question, but it's been frustrating me... I am using C#, by the way. I'd like to make a few classes, each with their own properties and methods. I would also like to have a database to store certain instances of these classes in case I would ever need to look at them again. So, for example... class Polygon { String name; Double perimiter; int numSides; public Double GetArea() { // ... } } class Circle { String name; Double radius; public void PrintName() { // ... } } Say I've got these classes. I also want a database that has the TABLES "Polygon" and "Circle" with the COLUMNS "name" "perimeter" "radius" etc. And I want an easy way to save a class instance into the database, or pull a class instance out of the database. I have previously been using MS Access for my database stuff, which I don't mind using, but I would prefer if nothing other than .NET need to be installed. I've been researching online a bit, but I wanted to get some opinions on here. I have looked at Linq-to-Sql, but it seems you need Sql-Server. Is this true? If so, I'd really rather not use it because I don't want to have to have it installed everywhere. Anway, I'm just fishing for some ideas/insights/suggestions/etc. so please help me out if you can. Thanks.

  Read the article

• When to define SDD(System Sequence Diagram) operations System->Actor?

  - by devoured elysium

  I am having some trouble understanding how to make System Sequence Diagrams, as I don't fully grasp why in some cases one should define operations for System - Actor and in others don't. Here is an example: Let's assume the System is a Cinema Ticket Store and the Actor is a client that wants to buy a ticket. 1) The User tells the System that wants to buy some tickets, stating his client number. 2) The System confirms that the given client number is valid. 3) The User tells the System the movie that wants to see. 4) The System shows the set of available sessions and seats for that movie. 5) The System asks the user which session/seat he wants. 6) The User tells the System the chosen session/seat. This would be converted to: a) -----> tellClientNumber(clientNumber) b) <----- validClientNumber c) -----> tellMovieToSee(movie) d) <----- showsAvailableSeatsHours e) -----> tellSystemChosenSessionSeat(session, seat) I know that when we are dealing with SDD's we are still far away from coding. But I can't help trying to imagine how it how it would have been had I to convert it right away to code: I can understand 1) and 2). It's like if it was a C#/Java method with the following signature: boolean tellClientNumber(clientNumber) so I put both on the SDD. Then, we have the pair 3) 4). I can imagine that as something as: SomeDataStructureThatHoldsAvailableSessionsSeats tellSystemMovieToSee(movie) Now, the problem: From what I've come to understand, my lecturer says that we shouldn't make an operation on the SDD for 5) as we should only show operations from the Actor to the System and when the System is either presenting us data (as in c)) or validating sent data (such as in b)). I find this odd, as if I try to imagine this like a DOS app where you have to put your input sequencially, it makes sense to make an arrow even for 5). Why is this wrong? How should I try to visualize this? Thanks

  Read the article

• MySQL Join/Comparison on a DATETIME column (<5.6.4 and > 5.6.4)

  - by Simon

  Suppose i have two tables like so: Events ID (PK int autoInc), Time (datetime), Caption (varchar) Position ID (PK int autoinc), Time (datetime), Easting (float), Northing (float) Is it safe to, for example, list all the events and their position if I am using the Time field as my joining criteria? I.e.: SELECT E.*,P.* FROM Events E JOIN Position P ON E.Time = P.Time OR, even just simply comparing a datetime value (taking into consideration that the parameterized value may contain the fractional seconds part - which MySQL has always accepted) e.g. SELECT E.* FROM Events E WHERE E.Time = @Time I understand MySQL (before version 5.6.4) only stores datetime fields WITHOUT milliseconds. So I would assume this query would function OK. However as of version 5.6.4, I have read MySQL can now store milliseconds with the datetime field. Assuming datetime values are inserted using functions such as NOW(), the milliseconds are truncated (<5.6.4) which I would assume allow the above query to work. However, with version 5.6.4 and later, this could potentially NOT work. I am, and only ever will be interested in second accuracy. If anyone could answer the following questions would be greatly appreciated: In General, how does MySQL compare datetime fields against one another (consider the above query). Is the above query fine, and does it make use of indexes on the time fields? (MySQL < 5.6.4) Is there any way to exclude milliseconds? I.e. when inserting and in conditional joins/selects etc? (MySQL 5.6.4) Will the join query above work? (MySQL 5.6.4) EDIT I know i can cast the datetimes, thanks for those that answered, but i'm trying to tackle the root of the problem here (the fact that the storage type/definition has been changed) and i DO NOT want to use functions in my queries. This negates all my work of optimizing queries applying indexes etc, not to mention having to rewrite all my queries. EDIT2 Can anyone out there suggest a reason NOT to join on a DATETIME field using second accuracy?

  Read the article

• Transaction within a Transaction in C#

  - by Rosco

  I'm importing a flat file of invoices into a database using C#. I'm using the TransactionScope to roll back the entire operation if a problem is encountered. It is a tricky input file, in that one row does not necessary equal one record. It also includes linked records. An invoice would have a header line, line items, and then a total line. Some of the invoices will need to be skipped, but I may not know it needs to be skipped until I reach the total line. One strategy is to store the header, line items, and total line in memory, and save everything once the total line is reached. I'm pursuing that now. However, I was wondering if it could be done a different way. Creating a "nested" transaction around the invoice, inserting the header row, and line items, then updating the invoice when the total line is reached. This "nested" transaction would roll back if it is determined the invoice needs to be skipped, but the overall transaction would continue. Is this possible, practical, and how would you set this up?

  Read the article

• Two references to the same domain/entity model

  - by Sbossb

  Problem I want to save the attributes of a model that have changed when a user edits them. Here's what I want to do ... Retrieve edited view model Get domain model and map back updated value Call the update method on repository Get the "old" domain model and compare values of the fields Store the changed values (in JSON) into a table However I am having trouble with step number 4. It seems that the Entity Framework doesn't want to hit the database again to get the model with the old values. It just returns the same entity I have. Attempted Solutions I have tried using the Find() and the SingleOrDefault() methods, but they just return the model I currently have. Example Code private string ArchiveChanges(T updatedEntity) { //Here is the problem! //oldEntity is the same as updatedEntity T oldEntity = DbSet.SingleOrDefault(x => x.ID == updatedEntity.ID); Dictionary<string, object> changed = new Dictionary<string, object>(); foreach (var propertyInfo in typeof(T).GetProperties()) { var property = typeof(T).GetProperty(propertyInfo.Name); //Get the old value and the new value from the models var newValue = property.GetValue(updatedEntity, null); var oldValue = property.GetValue(oldEntity, null); //Check to see if the values are equal if (!object.Equals(newValue, oldValue)) { //Values have changed ... log it changed.Add(propertyInfo.Name, newValue); } } var ser = new System.Web.Script.Serialization.JavaScriptSerializer(); return ser.Serialize(changed); } public override void Update(T entityToUpdate) { //Do something with this string json = ArchiveChanges(entityToUpdate); entityToUpdate.AuditInfo.Updated = DateTime.Now; entityToUpdate.AuditInfo.UpdatedBy = Thread.CurrentPrincipal.Identity.Name; base.Update(entityToUpdate); }

  Read the article

• Indexing table with duplicates MySQL/SQL Server with millions of records

  - by Tesnep

  I need help in indexing in MySQL. I have a table in MySQL with following rows: ID Store_ID Feature_ID Order_ID Viewed_Date Deal_ID IsTrial The ID is auto generated. Store_ID goes from 1 - 8. Feature_ID from 1 - let's say 100. Viewed Date is Date and time on which the data is inserted. IsTrial is either 0 or 1. You can ignore Order_ID and Deal_ID from this discussion. There are millions of data in the table and we have a reporting backend that needs to view the number of views in a certain period or overall where trial is 0 for a particular store id and for a particular feature. The query takes the form of: select count(viewed_date) from theTable where viewed_date between '2009-12-01' and '2010-12-31' and store_id = '2' and feature_id = '12' and Istrial = 0 In SQL Server you can have a filtered index to use for Istrial. Is there anything similar to this in MySQL? Also, Store_ID and Feature_ID have a lot of duplicate data. I created an index using Store_ID and Feature_ID. Although this seems to have decreased the search period, I need better improvement than this. Right now I have more than 4 million rows. To search for a particular query like the one above, it looks at 3.5 million rows in order to give me the count of 500k rows. PS. I forgot to add view_date filter in the query. Now I have done this.

  Read the article

• How to load/save C++ class instance (using STL containers) to disk

  - by supert

  I have a C++ class representing a hierarchically organised data tree which is very large (~Gb, basically as large as I can get away with in memory). It uses an STL list to store information at each node plus iterators to other nodes. Each node has only one parent, but 0-10 children. Abstracted, it looks something like: struct node { public: node_list_iterator parent; // iterator to a single parent node double node_data_array[X]; map<int,node_list_iterator> children; // iterators to child nodes }; class strategy { private: list<node> tree; // hierarchically linked list of nodes struct some_other_data; public: void build(); // build the tree void save(); // save the tree from disk void load(); // load the tree from disk void use(); // use the tree }; I would like to implement the load() and save() to disk, and it should be fairly fast, however the obvious problems are: I don't know the size in advance; The data contains iterators, which are volatile; My ignorance of C++ is prodigious. Could anyone suggest a pure C++ solution please?

  Read the article

• Should core application configuration be stored in the database, and if so what should be done to se

  - by Rl

  I'm writing an application around a lot of hierarchical data. Currently the hierarchy is fixed, but it's likely that new items will be added to the hierarchy in the future. (please let them be leaves) My current application and database design is fairly generic and nothing dealing with specific nodes in the hierarchy is hardcoded, with the exception of validation and lookup functions written to retrieve external data from each node's particular database. This pleases me from a design point of view, but I'm nervous at the realization that the entire application rests on a handful of records in the database. I'm also frustrated that I have to enforce certain aspects of data integrity with database triggers rather than by foreign key constraints (an example is where several different nodes in the hierarchy have their own proprietary IDs and I store them in a single column which, when coupled with the node ID can be used to locate the foreign data). I'm starting to wonder whether it may have been appropriate to simply hardcoded these known nodes into the system so that it would be more "type safe" and less generic. How does one know when something should be hardcoded, and when it should be a configuration item? Is it just a cost-benefit analysis of clarity/safety now vs less work later, or am I missing some metric I should be using to determine whether or not this is appropriate. The steps I'm taking to protect these valuable configurations are to add triggers that prevent updates/deletes. The database user that this application uses will only have the ability to manipulate data through stored procedures. What else can I do?

  Read the article

• Stable/repeatable random sort (MySQL, Rails)

  - by Matt Rogish

  I'd like to paginate through a randomly sorted list of ActiveRecord models (rows from MySQL database). However, this randomization needs to persist on a per-session basis, so that other people that visit the website also receive a random, paginate-able list of records. Let's say there are enough entities (tens of thousands) that storing the randomly sorted ID values in either the session or a cookie is too large, so I must temporarily persist it in some other way (MySQL, file, etc.). Initially I thought I could create a function based on the session ID and the page ID (returning the object IDs for that page) however since the object ID values in MySQL are not sequential (there are gaps), that seemed to fall apart as I was poking at it. The nice thing is that it would require no/minimal storage but the downsides are that it is likely pretty complex to implement and probably CPU intensive. My feeling is I should create an intersection table, something like: random_sorts( sort_id, created_at, user_id NULL if guest) random_sort_items( sort_id, item_id, position ) And then simply store the 'sort_id' in the session. Then, I can paginate the random_sorts WHERE sort_id = n ORDER BY position LIMIT... as usual. Of course, I'd have to put some sort of a reaper in there to remove them after some period of inactivity (based on random_sorts.created_at). Unfortunately, I'd have to invalidate the sort as new objects were created (and/or old objects being removed, although deletion is very rare). And, as load increases the size/performance of this table (even properly indexed) drops. It seems like this ought to be a solved problem but I can't find any rails plugins that do this... Any ideas? Thanks!!

  Read the article

< Previous Page | 435 436 437 438 439 440 441 442 443 444 445 446  | Next Page >