Search Results

Search found 22641 results on 906 pages for 'case'.

Page 513/906 | < Previous Page | 509 510 511 512 513 514 515 516 517 518 519 520  | Next Page >

  • Load Balancing and Failover for Read-Only PostgreSQL Database

    - by Eric J.
    Scenario Multiple application servers host web services written in Java, running in SpringSource dm Server. To implement a new requirement, they will need to query a read-only PostgreSQL database. Issue To support redundancy, at least two PostgreSQL instances will be running. Access to PostgreSQL must be load balanced and must auto-fail over to currently running instances if an instance should go down. Auto-discovery of newly running instances is desirable but not required. Research I have reviewed the official PostgreSQL documentation on this issue. However, that focuses on the more general case of read/write access to the database. Top google results tend to lead to older newsgroup messages or dead projects such as Sequoia or DB Balancer, as well as one active project PG Pool II Question What are your real-world experiences with PG Pool II? What other simple and reliable alternatives are available?

    Read the article

  • Efficient calculation of matrix cumulative standard deviation in r

    - by Abiel
    I recently posted this question on the r-help mailing list but got no answers, so I thought I would post it here as well and see if there were any suggestions. I am trying to calculate the cumulative standard deviation of a matrix. I want a function that accepts a matrix and returns a matrix of the same size where output cell (i,j) is set to the standard deviation of input column j between rows 1 and i. NAs should be ignored, unless cell (i,j) of the input matrix itself is NA, in which case cell (i,j) of the output matrix should also be NA. I could not find a built-in function, so I implemented the following code. Unfortunately, this uses a loop that ends up being somewhat slow for large matrices. Is there a faster built-in function or can someone suggest a better approach? cumsd <- function(mat) { retval <- mat*NA for (i in 2:nrow(mat)) retval[i,] <- sd(mat[1:i,], na.rm=T) retval[is.na(mat)] <- NA retval } Thanks.

    Read the article

  • rails ajax redirect

    - by badnaam
    Here is my use case I have a search model with two actions search_set and search_show. 1 - A user loads the home page which contains a search_form, rendered via a partial (search_form). 2 - User does a search, and the request goes to search_set, the search is saved and a redirect happens to search_show page which again renders the search_form with the saved search preferences. This search form is different than the one if step1, because it's a remote form being submitted to the same action (search set) 3 - Now the user does another search, and the search form is submitted via ajax to the search_set action. The search is saved and executed and now I need to present the result via rjs templates (corresponding to search_show). I am told that if the request is xhr then I can't redirect to the search_show action? Is that right? If yes, how do I handle this? Here is my controller class http://pastie.org/993460 Thanks

    Read the article

  • Latex: stretchable curly braces outside math

    - by basweber
    Hi, I am producing some latex beamer slides (but I think it is not a beamer specific question per se). I have the following: \begin{itemize} \item Issue1 \item Issue2 \item Issue3 \end{itemize} Now, I want to have a right curly brace (i.e. '}') behind the items spreading over issue1 and issue2. And of course I want to write something behind that curly brace. In a perfect world I would write something like: \begin{itemize} \left . \item Issue1 \item Issue2 \right \} One and Two are cool \item Issue3 \end{itemize} This does not work because I am not in a math environment and I can not put the whole snippet inside a math environment because itemize would not work in that case. Is there a clean solution or a hack to produce my desired result? Regards, Bastian.

    Read the article

  • git: having 2 push/pull repos in sync (or 1 push/pull and 1 pull in sync)

    - by xavjuan
    Hello, We work on multiple geographically seperate sites. Today I have our git clones all live on one site A. Then users from site B have to ssh over to do a git clone or to push in changes. These are bare repos where the update is through pushes. Ideally, for git clone/push performance, I'd like to limit having to go over ssh. I'd like to have a copy of git repo X live on site A and site B... and have some syncing mechanism between them. OR to have X live on both sites, but only allow pushing to A (and have that setup correctly at clone time on B) I'm worried about the case where someone on site A pushes changes to the repo at site A at the same time that someone on site B pushes a truely conflicting change to the repo at site B. Is there some 'sync'ing solution built into git for distributed open repos like this? Or a way to have a clone from X set the origin/parent to the X from the other site? thanks, -John

    Read the article

  • Floating point equality and tolerances

    - by doron
    Comparing two floating point number by something like a_float == b_float is looking for trouble since a_float / 3.0 * 3.0 might not be equal to a_float due to round off error. What one normally does is something like fabs(a_float - b_float) < tol. How does one calculate tol? Ideally tolerance should be just larger than the value of one or two of the least significant figures. So if the single precision floating point number is use tol = 10E-6 should be about right. However this does not work well for the general case where a_float might be very small or might be very large. How does one calculate tol correctly for all general cases? I am interested in C or C++ cases specifically.

    Read the article

  • Does anyone have a backup strategy for SQL Azure databases?

    - by Pete
    I'm using SQL Azure on a project and it works great. The problem is that the usual backup features do not exist. I have exported the database a couple of times using SQLAzureMW ( http://sqlazuremw.codeplex.com/ ) but this tool is now choking trying to download the database data with bcp. In any case, it's not as nice a solution as SQL Server backups. Is anyone aware of a commercial or open source tool, or other technique, for making reliable backups of SQL Azure databases? This is really a showstopper.

    Read the article

  • MS SQL replace sequence of same characters inside Text Field (TSQL only)

    - by zmische
    I have a text column varchar(4000) with text: 'aaabbaaacbaaaccc' and I need to remove all duplicated chars - so only one from sequence left: 'abacbac' It should not be a function, Procedure or CLR - Regex solution. Only true SQL select. Currently I think about using recursive WITH clause with replace 'aa'-'a', 'bb'-'b', 'cc'-'c'. So recursion should cycle until all duplicated sequences of that chars would be replaced. DO you have another solution, perhaps more Permormant one? PS: I searched through this site about different replace examples - they didnt suit to this case.

    Read the article

  • How to Select Multiple Records from Multiple Tables at Once - SQL Server/C#/.NET/T-SQL

    - by peace
    I have two tables Customer and CustomerPhone. Customer usually has multiple phone numbers, so when i run select statement on customer 101, i will get multiple records due to the multiple phone numbers. As you see below all the "Phone" and "Fax" field belongs to CustomerPhone table. These are considered as two records in the CustomerPhone table whereas the rest of fields relate to Customer table which is a single record. What should i do to fill Phone and Fax field in this case? Should i run select statement on CustomerPhone first and then run select statement on Customer?

    Read the article

  • Which design pattern should I be using?

    - by Gabriel
    Here's briefly what I'm trying to do. The user supplies me with a link to a photo from one of several photo-sharing websites (such as Flickr, Zooomr, et. al). I then do some processing on the photo using their respective APIs. Right now, I'm only implementing one service, but I will most likely add more in the near future. I don't want to have a bunch of if/else or switch statements to define the logic for the different websites (but maybe that's necessary?) I'd rather just call GetImage(url) and have it get me the image from whatever service the url's domain is from. I'm confused how the GetImage function and classes should be designed. Maybe I need the strategy pattern? I'm still reading and trying to understand the various design patterns and how I could make one fit in this case. I'm doing this in C#, but this question is language-agnostic.

    Read the article

  • Marionette multi user/roles application

    - by Fabrizio Fortino
    I have to build a pretty complex application using Backbone Marionette. The user interface has to handle multiple users with different roles. For example the 'admin' user will see the complete menu whereas the 'guest' user will access a subset of the same menu. Moreover some views will be accessible to all the users but the functions inside them (add, edit, delete) need to be profiled on the different roles. I am not sure about the right approach to use in order to solve this issue. I could have different templates for the different roles but in this case plenty of code will be duplicated inside them. Is there any best practice (or maybe some example) to sort my problem out using Marionette? Thanks in advance, Fabrizio

    Read the article

  • xml pahsing issue..

    - by 3gwebtrain
    HI, any one help me in this xml parsing issue? my xml is : name my jquery is : $(function(){ $.get("shop.xml", function(data){ var shopInfo = $(data).find("shop").attr('title'); var showowner = $(data).find("raj").attr('title'); alert(shopInfo+':'+showowner); }) }) when i alret in firefox it alret the shopInfo as "null" and showowner "title" and i case if i check with ie, and chrome, i am getting "null:null" in the alert message. any one tell me what is the wrong i am doing here? i need my jquery need to get xml data properly from to all browsers, for that any suggestion please?

    Read the article

  • Update tableview instantly as data pushed in core data iphone

    - by user336685
    I need to update the tableview as soon as the content is pushed in core data database. for this AppDelegate.m contains following code NSManagedObjectContext *moc = [self managedObjectContext]; NSFetchRequest *request = [[NSFetchRequest alloc] init]; [request setEntity:[NSEntityDescription entityForName:@"FeedItem" inManagedObjectContext:moc]]; //for loop // push data in code data & then save context [moc save:&error]; ZAssert(error == nil, @"Error saving context: %@", [error localizedDescription]); //for loop ends This code triggers following code from RootviewController.m - (void)controllerWillChangeContent:(NSFetchedResultsController*)controller { [[self tableView] beginUpdates]; } But this updates the tableview only at the end of the for loop ,the table does not get updated after immediate push in db. I tried following code but that didn't work - (void)controllerDidChangeContent:(NSFetchedResultsController *)controller { // In the simplest, most efficient, case, reload the table view. [self.tableView reloadData]; } I have been stuck with this problem for several days.Please help.Thanks in advance for solution.

    Read the article

  • Alternatives to nested interfaces (not possible in C#)

    - by ericdes
    I'm using interfaces in this case mostly as a handle to an immutable instance of an object. The problem is that nested interfaces in C# are not allowed. Here is the code: public interface ICountry { ICountryInfo Info { get; } // Nested interface results in error message: // Error 13 'ICountryInfo': interfaces cannot declare types public interface ICountryInfo { int Population { get; } string Note { get; } } } public class Country : ICountry { CountryInfo Info { get; set; } public class CountryInfo : ICountry.ICountryInfo { int Population { get; set; } string Note { get; set; } ..... } ..... } I'm looking for an alternative, anybody would have a solution?

    Read the article

  • How can I create an .xls file with a readwrite password from Delphi

    - by dummzeuch
    I know that it is possible to create .xls files from Delphi using ADO, OLE automation with Excel and even using several commercial libraries. My requirement now is not just creating a new .xls file and adding data to it but in addition protecting it with a password against editing. I guess this would be possible using OLE automation but that would require an Excel installation on the computer and also add all the potential hassle of OLE automation which I would like to avoid. Does any of the other solutions provide the option of password protecting the file? (Yes, I know this is far from secure, but the customer requests it. Just in case it matters: I am using Delphi 2007.)

    Read the article

  • Using the value of a variable as another variables name in Ruby

    - by hrickards
    Hi, I'm just starting out in learning Ruby and I've written a program that generates some numbers and assigns them to variables @one, @two, @three etc. The user can then specify a variable to change by inputting it's name (e.g one). I then need to do something like '@[valueofinout] = asd'. How would I do this, and is there a better way as the way I'm thinking of seems to be discouraged? I've found x = "myvar" myvar = "hi" eval(x) -> "hi" but I don't completely understand why the second line is needed. In my case would I use something like @one = "21" input = "one" input = "@" + input changeto = "22" eval(input) -> changeto Thanks

    Read the article

  • How to build an easy Rails authentication with OpenID and OAuth1.0a-2.0?

    - by Andrei
    Hi, I'am looking for an easy authentication for my users mostly via facebook, but keeping OpenID and other OAuth alternatives as well. For the case if something will go very bad, I will ask my users to optionally provide their email address, which should be obtained via OpenID or OAuth if possible. The same thing is about their name. I am a newbie in Rails, so I started with Railscasts.com #160 (authlogic) and #170 (authlogic and OpenID), however, I had some problems trying to sign in with my Google Account. As I understand, it will take some effort to adjust #170 for my objectives. On the other hand, there is gem authlogic_rpx which will possibly provide me the needed functionality (see http://rails-authlogic-rpx-sample.heroku.com/signin). What would you do? Is it reasonable to put one more step (RPX) in the authentication logic?

    Read the article

  • logrotate compress files after the postrotate script

    - by Thomas
    I have an application generating a really heavy big log file every days (~800MB a day), thus I need to compress them but since the compression takes time, I want that logrotate compress the file after reloading/sending HUP signal to the application. /var/log/myapp.log { rotate 7 size 500M compress weekly postrotate /bin/kill -HUP `cat /var/run/myapp.pid 2>/dev/null` 2>/dev/null || true endscript } Is it already the case that the compression takes place after the postrotate (which would be counter-intuitive)? If not Can anyone tell me if it's possible to do that without an extra command script (an option or some trick)? Thanks Thomas

    Read the article

  • watchpoint in GDB

    - by Tim
    Hi, If I set a watchpoint for a variable local to the current scope, it will be auto deleted when going out of the scope. Is there any way to set it once and keep it auto alive whenever entering the same scope? Is there anyway to set conditional watchpoint, like "watch var1 if var1==0"? In my case, the condition does't work. gdb stops whenever var1's value is changed, instead of untill "var1==0" is true. My gdb is GNU gdb 6.8-debian. Thanks and regards!

    Read the article

  • mysql and .net: when using tableadapters I’m getting MySqlException “insert command denied for user”

    - by Deveti Putnik
    Hi! I am using mysql as db for my asp.net application. Here are the facts: I am using connection string from web.config which has both username and password. I can do SELECT with tableadapter. When I am trying to do INSERT with tableadapter, I am getting "mysqlexception insert command denied for user" error When I try to do INSERT programatically, i.e. using connection, command object, etc. everything is fine. In this case, I'm reading connection string from web.config, too. This can be only applied to GoDaddy hosting, but on local machine I don't have this kind of problems. Can anyone suggest what can I do to make it work on GoDaddy hosting? Regards, D

    Read the article

  • How do I detect when a cell's value has changed in Silverlight?

    - by jvenema
    Hey folks, I'm working in Silverlight, trying to figure out how to set a grid cell font color based on the contents of the cell. I have an ObservableCollection bound to a DataGrid, and my items implement INotifyPropertyChanged so the grid updates as I change the values; it's all working perfectly, including letting me sort items and keep the sorting while I update the underlying items. I know I can use the LoadingRow event to change colors, but the only way I can get the event to fire is by changing the grids datasource, in which case my sorting goes out the window. So, what I really want is a way to either 1) loop the rows in the datagrid, find the cell I need, and change it's color or 2) implement a custom column that I can use to dynamically set the color. The problem is how to actually do either of those things :) All suggestions welcome.

    Read the article

  • Optimal password salt length

    - by Juliusz Gonera
    I tried to find the answer to this question on Stack Overflow without any success. Let's say I store passwords using SHA-1 hash (so it's 160 bits) and let's assume that SHA-1 is enough for my application. How long should be the salt used to generated password's hash? The only answer I found was that there's no point in making it longer than the hash itself (160 bits in this case) which sounds logical, but should I make it that long? E.g. Ubuntu uses 8-byte salt with SHA-512 (I guess), so would 8 bytes be enough for SHA-1 too or maybe it would be too much?

    Read the article

  • What is the best solution to do Reporting on Object data for .NET ?

    - by Peter Fox
    Hi, Our projects are using objects as the data source to reports. Our business layer is returning single objects or IEnumerable. Our reports (quite complex) need to display value-type properties of the object, and its related objects. Typical case would be, from a List, display a master report with category data, then a subreport with data for each Product inside each Category, then a subreport for each Part of each Product, and so on. Reporting from the database is not an option for us. We have tried so far - Reporting Services : works but have to mess around with the XML definition of the report to define the datasource classes, very hard to work with if you use an object datasource, architecturally not too clean - Telerik Reports : quite nice (esp., nice architecture) but seems to have problems with complex reports (master/sub), does not give great paging control, rumored to have performance/crash problems (immature product). Does anyone know a good reporting solution that can be integrated in an ASP.NET application and works well with objects as datasources ?

    Read the article

  • Connecting my flex application to Restlet webservices

    - by Vatsala
    Hi, I am doing some trial testing awith Amazon ec2 boxes, deploying flex apps running on top of restlet powered webservices. I have this problem - Everytime i deploy the app to the cloud, I'm having to hardcode the IP address of the server into the ActionScript/MXML files (http://72.93.48.39:8080/xxx/abc/) and for certain reasons, i am forced to choose a different IP everytime. and i think its really not the right way to deploy the application. I would like to know what other people do in such scenarios? On thinking about it, i thought i could make it pickup values from the HTMLVars of the HTML wrapper. but that again has to be edited everytime again and again. will it be possible to be able to supply these values : server's ip address, server's port number(in case its not 8080 on some machine) at build time? if so can anyone give me a barbones sample build.xml just as an example?

    Read the article

  • What is the best possible technology for pulling huge data from 4 remote servers

    - by Habib Ullah Bahar
    Hello, For one of our project, we need to pull huge real time stock data from 4 remote servers across two countries. The trivial process here, check the sources for a regular interval and save the update to database. But as these are real time stock data of more than 1000 companies, I have to pull every second, which isn't good in case of memory, bandwidth I think. Please give me suggestion on which technology/platform [We are flexible here. PHP, Python, Java, PERL - anyone of them will be OK for us] we should choose, it can be achieved easily and with better performance.

    Read the article

< Previous Page | 509 510 511 512 513 514 515 516 517 518 519 520  | Next Page >