Search Results

Search found 15116 results on 605 pages for 'customer experience'.

Page 527/605 | < Previous Page | 523 524 525 526 527 528 529 530 531 532 533 534  | Next Page >

  • Monads and custom traversal functions in Haskell

    - by Bill
    Given the following simple BST definition: data Tree x = Empty | Leaf x | Node x (Tree x) (Tree x) deriving (Show, Eq) inOrder :: Tree x -> [x] inOrder Empty = [] inOrder (Leaf x) = [x] inOrder (Node root left right) = inOrder left ++ [root] ++ inOrder right I'd like to write an in-order function that can have side effects. I achieved that with: inOrderM :: (Show x, Monad m) => (x -> m a) -> Tree x -> m () inOrderM f (Empty) = return () inOrderM f (Leaf y) = f y >> return () inOrderM f (Node root left right) = inOrderM f left >> f root >> inOrderM f right -- print tree in order to stdout inOrderM print tree This works fine, but it seems repetitive - the same logic is already present in inOrder and my experience with Haskell leads me to believe that I'm probably doing something wrong if I'm writing a similar thing twice. Is there any way that I can write a single function inOrder that can take either pure or monadic functions?

    Read the article

  • MongoDB - proper use of collections?

    - by zmg
    In Mongo my understanding is that you can have databases and collections. I'm working on a social-type app that will have blogs and comments (among other things) and had previously be using MySQL and pretty heavy partitioning in an attempt to limit possible concurrency issues. With MySQL I've stuffed all my user data into a _user database with several tables to further partition the data (blogs, pages, etc). My immediate reaction with Mongo would be to create a 'users' database with one collection per user. In this way user 'zach' blog entries would go into the 'zach' collection with associated comments and such becoming sub-objects in the same collection. Basically like dynamically creating one table per user in MySQL, but apparently without the complexity and limitations that might impose. Of course since I haven't really used Mongo before I'm having trouble gauging the (ahem..) quality of this idea and the potential problems it might cause down the road. I'd like user data to be treated a lot like a users directory in a *nix environment where user created/non-shared (mostly) gets put into one place (currently with MySQL that would be the appname_users as mentioned above). Most of the users data will be specific to the users page(s). Some of the user data which is queried across all site users (searchable user profiles) is currently kept in a separate database/table and I expect things like this could be put into a appname_system database and be broken up into collections and/or application specific databases (appname_profiles). Anyway, since the available documentation on this is currently a little thin and my experience is extremely limited I thought I might find a little guidance from someone with a better working understanding of the system. On the plus side I'd really already been attempting to treat MySQL as a schema-less document-store and doing this with Mongo seems much more intuitive/sane/rational so I'm really looking forward to getting started. Thanks, Zach

    Read the article

  • Could Python's logging SMTP Handler be freezing my thread for 2 minutes?

    - by Oddthinking
    A rather confusing sequence of events happened, according to my log-file, and I am about to put a lot of the blame on the Python logger, which is a bold claim. I thought I should get some second opinions about whether what I am saying could be true. I am trying to explain why there is are several large gaps in my log file (around two minutes at a time) during stressful periods for my application when it is missing deadlines. I am using Python's logging module on a remote server, and have set-up, with a configuration file, for all logs of severity of ERROR or higher to be emailed to me. Typically, only one error will be sent at a time, but during periods of sustained problems, I might get a dozen in a minute - annoying, but nothing that should stress SMTP. I believe that, after a short spurt of such messages, the Python logging system (or perhaps the SMTP system it is sitting on) is encountering errors or congestion. The call to Python's log is then BLOCKING for two minutes, causing my thread to miss its deadlines. (I was smart enough to move the logging until after the critical path of the application - so I don't care if logging takes me a few seconds, but two minutes is far too long.) This seems like a rather awkward architecture (for both a logging system that can freeze up, and for an SMTP system (Ubuntu, sendmail) that cannot handle dozens of emails in a minute**), so this surprises me, but it exactly fits the symptoms. Has anyone had any experience with this? Can anyone describe how to stop it from blocking? ** EDIT: I actually counted. A little under 4000 short emails in two hours. So far more than I suggested, sorry. But enough to over-fill a Sendmail's buffers?

    Read the article

  • Listing serial (COM) ports on Windows?

    - by Eli Bendersky
    Hello, I'm looking for a robust way to list the available serial (COM) ports on a Windows machine. There's this post about using WMI, but I would like something less .NET specific - I want to get the list of ports in a Python or a C++ program, without .NET. I currently know of two other approaches: Reading the information in the HARDWARE\\DEVICEMAP\\SERIALCOMM registry key. This looks like a great option, but is it robust? I can't find a guarantee online or in MSDN that this registry cell indeed always holds the full list of available ports. Tryint to call CreateFile on COMN with N a number from 1 to something. This isn't good enough, because some COM ports aren't named COMN. For example, some virtual COM ports created are named CSNA0, CSNB0, and so on, so I wouldn't rely on this method. Any other methods/ideas/experience to share? Edit: by the way, here's a simple Python implementation of reading the port names from registry: import _winreg as winreg import itertools def enumerate_serial_ports(): """ Uses the Win32 registry to return a iterator of serial (COM) ports existing on this computer. """ path = 'HARDWARE\\DEVICEMAP\\SERIALCOMM' try: key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, path) except WindowsError: raise IterationError for i in itertools.count(): try: val = winreg.EnumValue(key, i) yield (str(val[1]), str(val[0])) except EnvironmentError: break

    Read the article

  • Codeplex/Sourceforge for internal use

    - by Josh
    I'm looking for a free/open source collaborative project manager that can be deployed internally in my workplace that would act similar to Codeplex or Sourceforge. Does anyone know of something like this, and if so do you have experience with it. Requirements: Open Source or Free Locally Deployable Has the same types of features found in Sourceforge / Codeplex Issue/Feature Tracking Community Interaction (ie. Voting, Roles, etc.) SCM Integration (Optional) .NET/Windows Friendly (Optional) Every business ends up having internal utilities, and domain specific apps that developers create to make life easier. Given the input of the internal developer community they have the potential to become much better (can you say GMail...), and I would simply like to foster such an environment internally by providing an easy place for that interaction to take place. UPDATE: So I like what I am seeing in both Trac and GForge, but both are heavily geared towards UNIX/Subversion environments. I should have specified this, but we are a MS shop from top to bottom. How practical do you think it is going to be to try and use these in a MS .NET environment? Would that be like trying to shove a square peg through a round hole?

    Read the article

  • How much of STL is too much?

    - by Darius Kucinskas
    I am using a lot of STL code with std::for_each, bind, and so on, but I noticed that sometimes STL usage is not good idea. For example if you have a std::vector and want to do one action on each item of the vector, your first idea is to use this: std::for_each(vec.begin(), vec.end(), Foo()) and it is elegant and ok, for a while. But then comes the first set of bug reports and you have to modify code. Now you should add parameter to call Foo(), so now it becomes: std::for_each(vec.begin(), vec.end(), std::bind2nd(Foo(), X)) but that is only temporary solution. Now the project is maturing and you understand business logic much better and you want to add new modifications to code. It is at this point that you realize that you should use old good: for(std::vector::iterator it = vec.begin(); it != vec.end(); ++it) Is this happening only to me? Do you recognise this kind of pattern in your code? Have you experience similar anti-patterns using STL?

    Read the article

  • Music meta missing from Facebook /home

    - by Peter Watts
    When somebody shares a Spotify playlist, the attachment is missing from the Graph API. What is shown in Facebook: What is returned by the Graph API: { "id": "********_******", "from": { "name": "*****", "id": "*****" }, "message": "Refused's setlist from last night's secret show in Sweden...", "icon": "http://photos-c.ak.fbcdn.net/photos-ak-snc1/v85005/74/174829003346/app_2_174829003346_5511.gif", "actions": [ { "name": "Comment", "link": "http://www.facebook.com/*****/posts/*****" }, { "name": "Like", "link": "http://www.facebook.com/*****/posts/*****" }, { "name": "Get Spotify", "link": "http://www.spotify.com/redirect/download-social" } ], "type": "link", "application": { "name": "Spotify", "canvas_name": "get-spotify", "namespace": "get-spotify", "id": "174829003346" }, "created_time": "2012-03-01T22:24:28+0000", "updated_time": "2012-03-01T22:24:28+0000", "likes": { "data": [ { "name": "***** *****", "id": "*****" } ], "count": 1 }, "comments": { "count": 0 }, "is_published": true } There's absolutely no reference to an attachment, other than the fact the type is 'link' and the application is Spotify. If you want to test, Spotify's page (http://graph.facebook.com/spotify/feed) usually has a playlist or two embedded (and missing from Graph API). Also if you filter your home feed to just Spotify stories (http://graph.facebook.com/me/home?filter=app_174829003346), you'll get a bunch of useless stories without attachments (assuming your friends shared music recently) Anyone have any ideas how to access the playlist details, or is it unavailable to third party developers (if so, this is a very a bad user experience, because the story makes no sense without the attachment). I am able to fetch scrobbles without any trouble using the user_actions.listens. Also, if there is a recent activity story, e.g. "Peter listened to The Shins", I am able to get information about the band. The problem only happens on attachments.

    Read the article

  • Please help debug this ASP.Net [VB] code. Trying to write to text file from SQL Server DB.

    - by NJTechGuy
    I am a PHP programmer. I have no .Net coding experience (last seen it 4 years ago). Not interested in code-behind model since this is a quick temporary hack. What I am trying to do is generate an output.txt file whenever the user submits new data. So an output.txt file if exists should be replaced with the new one. I want to write data in this format : 123|Java Programmer|2010-01-01|2010-02-03 124|VB Programmer|2010-01-01|2010-02-03 125|.Net Programmer|2010-01-01|2010-02-03 I don't know VB, so not sure about string manipulations. Hope a kind soul can help me with this. I will be grateful to you. Thank you :) <%@ Import Namespace="System.IO" %> <%@ Import Namespace="System.Data" %> <%@ Import Namespace="System.Data.SqlClient" %> <script language="vb" runat="server"> sub Page_Load(sender as Object, e as EventArgs) Dim sqlConn As New SqlConnection("Data Source=winsqlus04.1and1.com;Initial Catalog=db28765269;User Id=dbo2765469;Password=ByhgstfH;") Dim myCommand As SqlCommand Dim dr As SqlDataReader Dim FILENAME as String = Server.MapPath("Output4.txt") Dim objStreamWriter as StreamWriter ' If Len(Dir$(FILENAME)) > 0 Then Kill(FILENAME) objStreamWriter = File.AppendText(FILENAME) Try sqlConn.Open() 'opening the connection myCommand = New SqlCommand("SELECT id, title, CONVERT(varchar(10), expirydate, 120) AS [expirydate],CONVERT(varchar(10), creationdate, 120) AS [createdate] from tblContact where flag = 0 AND ACTIVE = 1", sqlConn) 'executing the command and assigning it to connection dr = myCommand.ExecuteReader() While dr.Read() objStreamWriter.WriteLine("JobID: " & dr(0).ToString()) objStreamWriter.WriteLine("JobID: " & dr(2).ToString()) objStreamWriter.WriteLine("JobID: " & dr(3).ToString()) End While dr.Close() sqlConn.Close() Catch x As Exception End Try objStreamWriter.Close() Dim objStreamReader as StreamReader objStreamReader = File.OpenText(FILENAME) Dim contents as String = objStreamReader.ReadToEnd() lblNicerOutput.Text = contents.Replace(vbCrLf, "<br>") objStreamReader.Close() end sub </script> <asp:label runat="server" id="lblNicerOutput" Font-Name="Verdana" />

    Read the article

  • Singleton Issues in iOS http client

    - by Andrew Lauer Barinov
    I implemented an HTTP client is iOS that is meant to be a singleton. It is a subclass of AFNetworking's excellent AFHTTPClient My access method is pretty standard: + (LBHTTPClient*) sharedHTTPClient { static dispatch_once_t once = 0; static LBHTTPClient *sharedHTTPClient = nil; dispatch_once(&once, ^{ sharedHTTPClient = [[LBHTTPClient alloc] initHTTPClient]; }); return sharedHTTPClient; } // my init method - (id) initHTTPClient { self = [super initWithBaseURL:[NSURL URLWithString:kBaseURL]]; if (self) { // Sub class specific initializations } return self; } Super's init method is very long, and can be found here However the problem I experience is when the dispatch_once queue is run, the app locks and become unresponsive. When I step through code, I notice that it locks on dispatch_once and then remains frozen. Is this something to do with the main thread locking down? How come it stays locked like that? Also, none of the HTTP client methods fire. Stepping through the code some more, I find this line in dispatch/once.h is where the app locks down: DISPATCH_INLINE DISPATCH_ALWAYS_INLINE DISPATCH_NONNULL_ALL DISPATCH_NOTHROW void _dispatch_once(dispatch_once_t *predicate, dispatch_block_t block) { if (DISPATCH_EXPECT(*predicate, ~0l) != ~0l) { dispatch_once(predicate, block); // App locks here } }

    Read the article

  • Cygwin Cruisecontrol cannot execute commands

    I'm having what I hope to be a simple problem. However, it's had me stumped all day. I'm working with cruisecontrol in windows, being set up through Cygwin. I have some CC experience in the linux platform and much of what I'm doing is very similar. However, most any command I try to execute in the config.xml file's Schedule section is giving an error. Here's the exception: ExecBuilder - Could not execute command: /cygdrive/d/Program\ Files/Subversion/bin/svn net.sourceforge.cruisecontrol.CruiseControlException: Encountered an IO exception while attempting to execute 'net.sourceforge.cruisecontrol.builders.ExecScript@b80f1c'. CruiseControl cannot continue. at net.sourceforge.cruisecontrol.builders.ScriptRunner.runScript(ScriptRunner.java:133) Here are some examples of commands I've tried to run which give this type of error. <exec command="${CCLoc}/projects/${project.name}/IOSdllScript"/> -Runs a script that I tested outside of the cruisecontrol.bat and it runs. Includes #!/bin/sh as the first line <exec command="${CCLoc}/projects/${project.name}/EmptyFile"/> -Essentially an empty text file, proving that the problem had nothing to do with my script. <exec command="/cygdrive/d/Program\ Files/Subversion/bin/svn" args="cleanup" workingdir="${svndir}"/> -Trys svn cleanup on a directory. I double checked the pathing and spelling. One command that I tested worked and didn't give this error. That command was touch. <exec command="touch" args="ABC.txt"/> I'm not sure why only touch seems to work and nothing else does. Thank you for your help.

    Read the article

  • WPF deployment strategy dilemma.clickonce(limited customization)+autoupdate vs installer(unlimited c

    - by black sensei
    Hello Experts!!! I've been facing a deployment problem.I've built a WPF application with visual studio 2008 and created an installer(msi) which works fine.But then it's pain to add automatic update to it. i've seen this article at windowsclient.net but it seems to be pretty old but could have been the perfect thing for me.Then i looked at the .Net Application updater block v2.0 which uses enterprise library june 2005 and for some reason it's not installing on my machine. I thought i will need to use a more recent Enterprise library so i installed and compiled Enterprise 4.1(october 2008) but nothing better happened.To i decided to give a try to CLickonce deployment.After struggling with it, it was almost perfect.I realized that when i was testing the updates provided by the clickonce on my machine which is XP i didn't notice the need of having sqlite dll in the GAC. surely it was already there.I noticed it when i moved to vista that there is a problem.After checking the net i know it's impossible to add a dll to the Global Assembly Cache. Now i'm stuck, i think i've hit a wall.Can any one share some of his experience? I'm willing to try the updater block if i can get help. Thanks for reading this!!

    Read the article

  • How to restrain one's self from the overwhelming urge to rewrite everything?

    - by Scott Saad
    Setup Have you ever had the experience of going into a piece of code to make a seemingly simple change and then realizing that you've just stepped into a wasteland that deserves some serious attention? This usually gets followed up with an official FREAK OUT moment, where the overwhelming feeling of rewriting everything in sight starts to creep up. It's important to note that this bad code does not necessarily come from others as it may indeed be something we've written or contributed to in the past. Problem It's obvious that there is some serious code rot, horrible architecture, etc. that needs to be dealt with. The real problem, as it relates to this question, is that it's not the right time to rewrite the code. There could be many reasons for this: Currently in the middle of a release cycle, therefore any changes should be minimal. It's 2:00 AM in the morning, and the brain is starting to shut down. It could have seemingly adverse affects on the schedule. The rabbit hole could go much deeper than our eyes are able to see at this time. etc... Question So how should we balance the duty of continuously improving the code, while also being a responsible developer? How do we refrain from contributing to the broken window theory, while also being aware of actions and the potential recklessness they may cause? Update Great answers! For the most part, there seems to be two schools of thought: Don't resist the urge as it's a good one to have. Don't give in to the temptation as it will burn you to the ground. It would be interesting to know if more people feel any balance exists.

    Read the article

  • Pass a data.frame column name to a function

    - by Kevin Middleton
    I'm trying to write a function to accept a data.frame (x) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function. The two minimal examples fun1 and fun2 below produce the desired result, being able to perform operations on x$column, using max() as an example. However, both rely on the seemingly (at least to me) inelegant (1) call to substitute() and possibly eval() and (2) the need to pass the column name as a character vector. fun1 <- function(x, column){ do.call("max", list(substitute(x[a], list(a = column)))) } fun2 <- function(x, column){ max(eval((substitute(x[a], list(a = column))))) } df <- data.frame(A = 1:20, B = rnorm(10)) fun1(df, "B") fun2(df, "B") I would like to be able to call the function as fun(df, B), for example. Other options I have considered but have not tried: Pass column as an integer of the column number. I think this would avoid substitute(). Ideally, the function could accept either. with(x, get(column)), but, even if it works, I think this would still require substitute Make use of formula() and match.call(), neither of which I have much experience with. Subquestion: Is do.call() preferred over eval()? Thanks, Kevin

    Read the article

  • How to organize live data integrity tests and code unit tests?

    - by karlthorwald
    I have several files with code testing code (which uses a "unittest" class). Later I found it would be nice to test database integrity also. I put this into a separate directory tree. (Things like the keys have correct format, parent and child nodes are pointing correctly and such.) I use the same unittest class for the integrity tests. Now I wonder if it makes really sense to keep this separate. To test the integrity of data I often duplicate parts of code that I use to test the code that handles the data. But it is not the same. The code tests use test databases (that get deleted after each test) and the integrity tests connect to the live data and analyze it. The integrity tests I want to call from cron and send an alarm if something happens in the live database. How would you handle that? Are there standards for such a setup? What is your experience? My tendency is to put everything in the same file, which would result in the code tests also being executed by the cron on the production environment.

    Read the article

  • What is reading source on an ebook reader like?

    - by Daniel Straight
    There are a few open source projects I would really like to read through the code of to understand better / improve on. The problem is, for me, reading for a long time on the computer screen is tedious. I would love to be able to read code while lounging around and on a screen that was better on my eyes. Has anyone ever tried reading code on an ebook reader? It seems like the e-ink would make it easy on the eyes, plus it would be portable, plus it wouldn't kill any trees. In other words, it sounds perfect, but before I drop a couple benjamins on an ebook reader, I'd like to hear if anyone else has tried this and how it went. It seems Scott Hanselman discussed using the Kindle to read code, but I wouldn't necessarily want a Kindle. Has anyone had a positive experience with some other device? I realize this is not directly about programming, but it relates directly to my ability to improve my skills. I think if a good portable reading device for code exists, it could help a lot of programmers.

    Read the article

  • PHP CodeIgniter Framework - Thoughts on developing with it?

    - by Sootah
    I've been reviewing different frameworks to use for my next couple of major web applications, and after days of research am almost set on using CodeIgniter. The reason I'm leaning towards CI is that so far it looks to be the best suited for me. It doesn't require constant command-line access (I am currently using shared hosting; the projects do not warrant a dedicate server yet), nothing special has to be installed on the server running it (you just upload the framework to the root of whatever your developing), and they appear to have some excellent documentation, videos, and tutorials on how to get started. Do any of you have experience with CodeIgniter? If so, what is your opinion of it and its features? What had you developed with it, and what types of applications is it best suited to create? I certainly don't want to get into a situation where I'm trying to bend a framework to do something that it isn't well-suited for. Both of my projects will be database-driven apps that will require user registration, the ability to manipulate data that is specific to their account (their posts, listings, user account details, etc), amongst other things. Also, if you have any other PHP framework suggestions, I am open to them. Thanks in advance for your help! -Sootah

    Read the article

  • Dependency between operations in scala actors

    - by paradigmatic
    I am trying to parallelise a code using scala actors. That is my first real code with actors, but I have some experience with Java Mulithreading and MPI in C. However I am completely lost. The workflow I want to realise is a circular pipeline and can be described as the following: Each worker actor has a reference to another one, thus forming a circle There is a coordinator actor which can trigger a computation by sending a StartWork() message When a worker receives a StartWork() message, it process some stuff locally and sends DoWork(...) message to its neighbour in the circle. The neighbours do some other stuff and sends in turn a DoWork(...) message to its own neighbour. This continues until the initial worker receives a DoWork() message. The coordinator can send a GetResult() message to the initial worker and wait for a reply. The point is that the coordinator should only receive a result when data is ready. How can a worker wait that the job returned to it before answering the GetResult() message ? To speed up computation, any worker can receive a StartWork() at any time. Here is my first try pseudo-implementation of the worker: class Worker( neighbor: Worker, numWorkers: Int ) { var ready = Foo() def act() { case StartWork() => { val someData = doStuff() neighbor ! DoWork( someData, numWorkers-1 ) } case DoWork( resultData, remaining ) => if( remaining == 0 ) { ready = resultData } else { val someOtherData = doOtherStuff( resultData ) neighbor ! DoWork( someOtherData, remaining-1 ) } case GetResult() => reply( ready ) } } On the coordinator side: worker ! StartWork() val result = worker !? GetResult() // should wait

    Read the article

  • Scala programming language for beginners, is it a legend?

    - by ali
    Hi every one, I am Ali from Saudi Arabia. undoubtedly, Scala is one of the best programming language for any programmer to learn, but there is "good" problems that is faced especially by beginners, and what seems frustrating that these problems won't solve soon, so as a beginner and on behalf of beginners let me raise these "objective" questions: 1- why scala has no effective and stable development platform, in fact, it suffers many problems with Eclipse, Netbeat, and Intellij. 2- although I have looked for a clear,easy, and understandable explanation of how to get started with Scala, but fortunately, there was no article or guide that deserves to spend the time I have spent to read it. nobody could tell you clear steps that fit you as a beginner who wants to start his"HELLO WORLD" with Scala, while all other languages have its "HELLO WORLD" guides and books. thank you for your time, be sure that you read notes below. 1- I have no experience in programming language before. 2- don't tell me "not to begin with scala", simply, because I will do. 3- OS is windows vista home premium. 4- I hate excuses, such as Scala is new language......etc

    Read the article

  • Serial.begin(speed, config) not compiling for Leonardo Board

    - by forgemo
    I would like to configure my serial communication to have no parity, 1 start- and 2 stop-bits. The documentation for Serial.begin(speed, config) states: (...) An optional second argument configures the data, parity, and stop bits. The default is 8 data bits, no parity, one stop bit. The documentation also lists the possible configuration-values. According to my (limited) understanding, I need SERIAL_7N2 or SERIAL_8N2 to meet my requirements. (I'm not sure how the data-bits relate to the the 1-start-bit that I need.) However, I can't even compile because I have no idea how to supply that config value to the begin method. (I don't have much Arduino/C++ experience) I've tried in my code the following two variants: Serial.begin(9600, SERIAL_8N2); Serial.begin(9600, "SERIAL_8N2"); Am I missing something? Additional Information: Serial.begin(speed, config) has been introduced with the latest Arduino 1.0.2 IDE version. The code defining/implementing the begin methods can be found here. HardwareSerial.h HardwareSerial.cpp Edit: According to the replies from PeterJ and borges, the following variant is correct. Serial.begin(9600, SERIAL_8N2); However, it's still not working. I found that the compile error doesn't occur if I change the configured board from my Arduino Leonardo to Arduino uno. Therefore, it could be a bug occurring only with a subset of boards ... or maybe it's not supported?!

    Read the article

  • Is there an XML XQuery interface to existing XML files?

    - by xsaero00
    My company is in education industry and we use XML to store course content. We also store some course related information (mostly metainfo) in relational database. Right now we are in the process of switching from our proprietary XML Schema to DocBook 5. Along with the switch we want to move course related information from database to XML files. The reason for this is to have all course data in one place and to put it under Subversion. However, we would like to keep flexibility of the relational database and be able to easily extract specific information about a course from an XML document. XQuery seems to be up to the task so I was researching databases that supports it but so far could not find what I needed. What I basically want, is to have my XML files in a certain directory structure and then on top of this I would like to have a system that would index my files and let me select anything out of any file using XQuery. This way I can have "my cake and eat it too": I will have XQuery interface and still keep my files in plain text and versioned. Is there anything out there at least remotely resembling to what I want? If you think that what I an asking for is nonsense please make an alternative suggestion. On the related note: What XML Databases (preferably native and open source) do you have experience with and what would you recommend?

    Read the article

  • Is this OleDbDataAdapter bug

    - by ????
    It doesn't look to me OleDbDataAdapter should throw an exception on trying to fill DataSet for a db table column of type decimal(28,3). The message is "The numerical value is too large to fit into a 96 bit decimal". Could you just check this, I have no significant experience with ADO.NET and OLE DB components? The VB.NET code we have in the application is this: Dim dbDataSet As New DataSet Dim dbDataAdapter As OleDbDataAdapter Dim dbCommand As OleDbCommand Dim conn As OleDbConnection Dim connectionString As String 'parts where connectionString is set conn = New OleDbConnection(connectionString) 'part where sqlQuery is set but it ends up being "SELECT Price As 'Price' From PricebookView" - Price is of type decimal(28,3) dbCommand = New OleDbCommand(sqlQuery, conn) dbCommand.CommandTimeout = cmdTimeout dbDataAdapter = New OleDbDataAdapter(dbCommand) dbDataAdapter.Fill(dbDataSet) The last line is where the exception is thrown and the top of the stack trace is: at System.Data.ProviderBase.DbBuffer.ReadNumeric(Int32 offset) at System.Data.OleDb.ColumnBinding.Value_NUMERIC() at System.Data.OleDb.ColumnBinding.Value() at System.Data.OleDb.OleDbDataReader.GetValues(Object[] values) at System.Data.ProviderBase.DataReaderContainer.CommonLanguageSubsetDataReader.GetValues(Object[] values) at System.Data.ProviderBase.SchemaMapping.LoadDataRow() at System.Data.Common.DataAdapter.FillLoadDataRow(SchemaMapping mapping) at System.Data.Common.DataAdapter.FillFromReader(DataSet dataset, DataTable datatable, String srcTable, DataReaderContainer dataReader, Int32 startRecord, Int32 maxRecords, DataColumn parentChapterColumn, Object parentChapterValue) at System.Data.Common.DataAdapter.Fill(DataSet dataSet, String srcTable, IDataReader dataReader, Int32 startRecord, Int32 maxRecords) at System.Data.Common.DbDataAdapter.FillInternal(DataSet dataset, DataTable[] datatables, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) at System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) at System.Data.Common.DbDataAdapter.Fill(DataSet dataSet) ... I am not sure why does it try to set the value to Int32. Thank you for the time !

    Read the article

  • Slow retrieval of data in SQLITE takes a long using ContentProvider

    - by Arlyn
    I have an application in Android (running 4.0.3) that stores a lot of data in Table A. Table A resides in SQLite Database. I am using a ContentProvider as an abstraction layer above the database. Lots of data here means almost 80,000 records per month. Table A is structured like this: String SQL_CREATE_TABLE = "CREATE TABLE IF NOT EXISTS " + TABLE_A + " ( " + COLUMN_ID + " INTEGER PRIMARY KEY NOT NULL" + "," + COLUMN_GROUPNO + " INTEGER NOT NULL DEFAULT(0)" + "," + COLUMN_TIMESTAMP + " DATETIME UNIQUE NOT NULL" + "," + COLUMN_TAG + " TEXT" + "," + COLUMN_VALUE + " REAL NOT NULL" + "," + COLUMN_DEVICEID + " TEXT NOT NULL" + "," + COLUMN_NEW + " NUMERIC NOT NULL DEFAULT(1)" + " )"; Here is the index statement: String SQL_CREATE_INDEX_TIMESTAMP = "CREATE INDEX IF NOT EXISTS " + TABLE_A + "_" + COLUMN_TIMESTAMP + " ON " + TABLE_A + " (" + COLUMN_TIMESTAMP + ") "; I have defined the columns as well as the table name as String Constants. I am already experiencing significant slow down when retrieving this data from Table A. The problem is that when I retrieve data from this table, I first put it in an ArrayList and then I display it. Obviously, this is possibly the wrong way of doing things. I am trying to find a better way to approach this problem using a ContentProvider. But this is not the problem that bothers me. The problem is for some reason, it takes a lot longer to retrieve data from other tables which have only upto 12 records maximum. I see this delay increase as the number of records in Table A increase. This does not make any sense. I can understand the delay if I retrieve data from Table A, but why the delay in retrieving data from other tables. To clarify, I do not experience this delay if Table A is empty or has less than 3000 records. What could be the problem?

    Read the article

  • multithreading issue

    - by vbNewbie
    I have written a multithreaded crawler and the process is simply creating threads and having them access a list of urls to crawl. They then access the urls and parse the html content. All this seems to work fine. Now when I need to write to tables in a database is when I experience issues. I have 2 declared arraylists that will contain the content each thread parse. The first arraylist is simply the rss feed links and the other arraylist contains the different posts. I then use a for each loop to iterate one while sequentially incrementing the other and writing to the database. My problem is that each time a new thread accesses one of the lists the content is changed and this affects the iteration. I tried using nested loops but it did not work before and this works fine using a single thread.I hope this makes sense. Here is my code: SyncLock dlock For Each l As String In links finallinks.Add(l) Next End SyncLock SyncLock dlock For Each p As String In posts finalposts.Add(p) Next End SyncLock ... Dim i As Integer = 0 SyncLock dlock For Each rsslink As String In finallinks postlink = finalposts.Item(i) i = i + 1 finallinks and finalposts are the two arraylists. I did not include the rest of the code which shows the threads working but this is the essential part where my error occurs which is basically here postlink = finalposts.Item(i) i = i + 1 ERROR: index was out of range. Must be non-negative and less than the size of the collection Is there an alternative?

    Read the article

  • Django Testing: Faking User Creation

    - by Ygam
    I want to better write this test: def test_profile_created(self): self.client.post(reverse('registration_register'), data={ 'username':'ygam', 'email':'[email protected]', 'password1':'ygam', 'password2':'ygam' }) """ Test if a profile is created on save """ user = User.objects.get(username='ygam') self.assertTrue(UserProfile.objects.filter(user=user).exists()) and I just came upon this code on django-registration tests that does not actually "create" the user: def test_registration_signal(self): def receiver(sender, **kwargs): self.failUnless('user' in kwargs) self.assertEqual(kwargs['user'].username, 'bob') self.failUnless('request' in kwargs) self.failUnless(isinstance(kwargs['request'], WSGIRequest)) received_signals.append(kwargs.get('signal')) received_signals = [] signals.user_registered.connect(receiver, sender=self.backend.__class__) self.backend.register(_mock_request(), username='bob', email='[email protected]', password1='secret') self.assertEqual(len(received_signals), 1) self.assertEqual(received_signals, [signals.user_registered]) However he used a custom function for this "_mock_request": class _MockRequestClient(Client): def request(self, **request): environ = { 'HTTP_COOKIE': self.cookies, 'PATH_INFO': '/', 'QUERY_STRING': '', 'REMOTE_ADDR': '127.0.0.1', 'REQUEST_METHOD': 'GET', 'SCRIPT_NAME': '', 'SERVER_NAME': 'testserver', 'SERVER_PORT': '80', 'SERVER_PROTOCOL': 'HTTP/1.1', 'wsgi.version': (1,0), 'wsgi.url_scheme': 'http', 'wsgi.errors': self.errors, 'wsgi.multiprocess':True, 'wsgi.multithread': False, 'wsgi.run_once': False, 'wsgi.input': None, } environ.update(self.defaults) environ.update(request) request = WSGIRequest(environ) # We have to manually add a session since we'll be bypassing # the middleware chain. session_middleware = SessionMiddleware() session_middleware.process_request(request) return request def _mock_request(): return _MockRequestClient().request() However, it may be too long of a function for my needs. I want to be able to somehow "fake" the account creation. I have not much experience on mocks and stubs so any help would do. Thanks!

    Read the article

  • CommandBuilder and SqlTransaction to insert/update a row

    - by Jesse
    I can get this to work, but I feel as though I'm not doing it properly. The first time this runs, it works as intended, and a new row is inserted where "thisField" contains "doesntExist" However, if I run it a subsequent time, I get a run-time error that I can't insert a duplicate key as it violate the primary key "thisField". static void Main(string[] args) { using(var sqlConn = new SqlConnection(connString) ) { sqlConn.Open(); var dt = new DataTable(); var sqlda = new SqlDataAdapter("SELECT * FROM table WHERE thisField ='doesntExist'", sqlConn); sqlda.Fill(dt); DataRow dr = dt.NewRow(); dr["thisField"] = "doesntExist"; //Primary key dt.Rows.Add(dr); //dt.AcceptChanges(); //I thought this may fix the problem. It didn't. var sqlTrans = sqlConn.BeginTransaction(); try { sqlda.SelectCommand = new SqlCommand("SELECT * FROM table WITH (HOLDLOCK, ROWLOCK) WHERE thisField = 'doesntExist'", sqlConn, sqlTrans); SqlCommandBuilder sqlCb = new SqlCommandBuilder(sqlda); sqlda.InsertCommand = sqlCb.GetInsertCommand(); sqlda.InsertCommand.Transaction = sqlTrans; sqlda.DeleteCommand = sqlCb.GetDeleteCommand(); sqlda.DeleteCommand.Transaction = sqlTrans; sqlda.UpdateCommand = sqlCb.GetUpdateCommand(); sqlda.UpdateCommand.Transaction = sqlTrans; sqlda.Update(dt); sqlTrans.Commit(); } catch (Exception) { //... } } } Even when I can get that working through trial and error of moving AcceptChanges around, or encapsulating changes within Begin/EndEdit, then I begin to experience a "Concurrency violation" in which it won't update the changes, but rather tell me it failed to update 0 of 1 affected rows. Is there something crazy obvious I'm missing?

    Read the article

< Previous Page | 523 524 525 526 527 528 529 530 531 532 533 534  | Next Page >