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• How to implement message queuing and handling in AWS with NServiceBus

  - by Pete Lunenfeld

  I am creating a new ASP MVC order application in the Amazon (AWS) cloud with the persistence layer at my local datacenter. I will be using the CQRS pattern. The goal of the project is high availability using Queue(s) to store and forward writes (commands/events) that can be picked up and handled asynchronously at my local datacenter. Then, ff the WAN or my local datacenter fails, my cloud MVC app can still take orders and just queue them up until processing can resume. My first thought was to use AWS SQS for the queuing and create my own queue consumer/dispatcher/handler in my own c# application to process the incoming messages/events. MVC (@ Amazon) -- Event/POCO -- SQS -- QueueReader (@ my datacenter) -- DB Then I found NServiceBus. NSB seems to handle lots of details very nicely: message handling, retries, error handling, etc. I hate to reinvent the wheel, and NServiceBus seems like a full featured and mature product that would be perfect for me. But on further research, it does NOT look like NServiceBus is really meant to be used over the WAN in physically separated environments (Cloud to my Datacenter). Google and SO don't really paint a good picture of using NServiceBus across the WAN like I need. How can I use NServiceBus across the WAN? Or is there a better solution to handle queuing and message handling between Amazon an my local datacenter?

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• Doing a POST to a Service Operation in ADO.NET data services

  - by DataServices123

  Is it possible to POST to a service operation defined in an ADO.NET data service (it is decorated with WebInvoke)? I had no problem calling the service operation as an HTTP GET. However, when I switched to doing a POST, the stack trace consistently comes back with "Parameter cannot be NULL". I am using the jQuery syntax below, and sending the POST as JSON (though I'm not including the $.ajax call, the parameter names line up exactly). It would be possible to try this with WCF, as opposed to ADO.NET data services (newly renamed as WCF data services). However, my preference would be to use this approach first. I have tried this with and without the stringify method. Most examples online only show how to use a POST to entities (i.e. for handling CRUD operations). However, in this case we are POSTing to a Service Operation. function PostToDataService() { varType = "POST"; varUrl = "http://dev-server/MyServices/MyService.svc/SampleSO"; varData = { CustomMessage: $("#TextBox1").val() }; varData = JSON.stringify(varData); varContentType = "application/json; charset=utf-8"; varDataType = "json"; varProcessData = true; CallService(); }

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• Generics vs inheritance (when no collection classes are involved)

  - by Ram

  This is an extension of this questionand probably might even be a duplicate of some other question(If so, please forgive me). I see from MSDN that generics are usually used with collections The most common use for generic classes is with collections like linked lists, hash tables, stacks, queues, trees and so on where operations such as adding and removing items from the collection are performed in much the same way regardless of the type of data being stored. The examples I have seen also validate the above statement. Can someone give a valid use of generics in a real-life scenario which does not involve any collections ? Pedantically, I was thinking about making an example which does not involve collections public class Animal<T> { public void Speak() { Console.WriteLine("I am an Animal and my type is " + typeof(T).ToString()); } public void Eat() { //Eat food } } public class Dog { public void WhoAmI() { Console.WriteLine(this.GetType().ToString()); } } and "An Animal of type Dog" will be Animal<Dog> magic = new Animal<Dog>(); It is entirely possible to have Dog getting inherited from Animal (Assuming a non-generic version of Animal)Dog:Animal Therefore Dog is an Animal Another example I was thinking was a BankAccount. It can be BankAccount<Checking>,BankAccount<Savings>. This can very well be Checking:BankAccount and Savings:BankAccount. Are there any best practices to determine if we should go with generics or with inheritance ?

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• Groovy as a substitute for Java when using BigDecimal?

  - by geejay

  I have just completed an evaluation of Java, Groovy and Scala. The factors I considered were: readability, precision The factors I would like to know: performance, ease of integration I needed a BigDecimal level of precision. Here are my results: Java void someOp() { BigDecimal del_theta_1 = toDec(6); BigDecimal del_theta_2 = toDec(2); BigDecimal del_theta_m = toDec(0); del_theta_m = abs(del_theta_1.subtract(del_theta_2)) .divide(log(del_theta_1.divide(del_theta_2))); } Groovy void someOp() { def del_theta_1 = 6.0 def del_theta_2 = 2.0 def del_theta_m = 0.0 del_theta_m = Math.abs(del_theta_1 - del_theta_2) / Math.log(del_theta_1 / del_theta_2); } Scala def other(){ var del_theta_1 = toDec(6); var del_theta_2 = toDec(2); var del_theta_m = toDec(0); del_theta_m = ( abs(del_theta_1 - del_theta_2) / log(del_theta_1 / del_theta_2) ) } Note that in Java and Scala I used static imports. Java: Pros: it is Java Cons: no operator overloading (lots o methods), barely readable/codeable Groovy: Pros: default BigDecimal means no visible typing, least surprising BigDecimal support for all operations (division included) Cons: another language to learn Scala: Pros: has operator overloading for BigDecimal Cons: some surprising behaviour with division (fixed with Decimal128), another language to learn

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• Still Confused About Identifying vs. Non-Identifying Relationships

  - by Jason

  So, I've been reading up on identifying vs. non-identifying relationships in my database design, and a number of the answers on SO seem contradicting to me. Here are the two questions I am looking at: What's the Difference Between Identifying and Non-Identifying Relationships Trouble Deciding on Identifying or Non-Identifying Relationship Looking at the top answers from each question, I appear to get two different ideas of what an identifying relationship is. The first question's response says that an identifying relationship "describes a situation in which the existence of a row in the child table depends on a row in the parent table." An example of this that is given is, "An author can write many books (1-to-n relationship), but a book cannot exist without an author." That makes sense to me. However, when I read the response to question two, I get confused as it says, "if a child identifies its parent, it is an identifying relationship." The answer then goes on to give examples such as SSN (is identifying of a Person), but an address is not (because many people can live at an address). To me, this sounds more like a case of the decision between primary key and non-primary key. My own gut feeling (and additional research on other sites) points to the first question and its response being correct. However, I wanted to verify before I continued forward as I don't want to learn something wrong as I am working to understand database design. Thanks in advance.

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• How to upload files to server using JSP/Servlet?

  - by Thang Pham

  How can I upload files to server using JSP/Servlet? I tried this: <form action="upload" method="post"> <input type="text" name="description" /> <input type="file" name="file" /> <input type="submit" /> </form> However, I only get the file name, not the file content. When I add enctype="multipart/form-data" to the <form>, then request.getParameter() returns null. During research I stumbled upon Apache Common FileUpload. I tried this: FileItemFactory factory = new DiskFileItemFactory(); ServletFileUpload upload = new ServletFileUpload(factory); List items = upload.parseRequest(request); // This line is where it died. Unfortunately, the servlet threw an exception without a clear message and cause. Here is the stacktrace: SEVERE: Servlet.service() for servlet UploadServlet threw exception javax.servlet.ServletException: Servlet execution threw an exception at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:313) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Thread.java:637)

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• Providing custom database functionality to custom asp.net membership provider

  - by IrfanRaza

  Hello friends, I am creating custom membership provider for my asp.net application. I have also created a separate class "DBConnect" that provides database functionality such as Executing SQL statement, Executing SPs, Executing SPs or Query and returning SqlDataReader and so on... I have created instance of DBConnect class within Session_Start of Global.asax and stored to a session. Later using a static class I am providing the database functionality throughout the application using the same single session. In short I am providing a single point for all database operations from any asp.net page. I know that i can write my own code to connect/disconnect database and execute SPs within from the methods i need to override. Please look at the code below - public class SGI_MembershipProvider : MembershipProvider { ...... public override bool ChangePassword(string username, string oldPassword, string newPassword) { if (!ValidateUser(username, oldPassword)) return false; ValidatePasswordEventArgs args = new ValidatePasswordEventArgs(username, newPassword, true); OnValidatingPassword(args); if (args.Cancel) { if (args.FailureInformation != null) { throw args.FailureInformation; } else { throw new Exception("Change password canceled due to new password validation failure."); } } ..... //Database connectivity and code execution to change password. } .... } MY PROBLEM - Now what i need is to execute the database part within all these overriden methods from the same database point as described on the top. That is i have to pass the instance of DBConnect existing in the session to this class, so that i can access the methods. Could anyone provide solution on this. There might be some better techniques i am not aware of that. The approach i am using might be wrong. Your suggessions are always welcome. Thanks for sharing your valuable time.

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• Presenting collection of structures of strings in grid or similar in WPF - Example? Ideas?

  - by Andrew

  Hi, I have a collection of structures. The structure is just some strings. Example public struct ReportLine { public string Name; public string Address; public string Phone; ...// about 10 other strings } I can't change this part. What I want to do is display it in a simple grid or simlar in WPF. My only requirements are: a) need column headers b) rows must alternate in color c) columns big enough to hold largest datum (which is not know until run time) Can someone point me to an example to get me started? Is the GridView the way to go? Or DataGrid? Or perhaps just the grid? I have the book Pro WPF in C# 2008 and it covers binding ListBox's to collections, but the collections always seem to be collections of one field (ex. a collection of 40 names). Here I have a collection (an array in fact) of a structure. How do I setup the databinding? As you can see, I'm new to this and probably would most benefit from a reference to an article. I've found articles covering collections of 1 field, but no examples covering binding to an array of structures. Also, my intitial research indicates c) can't be easily done, if you demand that the column is big enough for all the data in that column, not just the visible data. Thanks, dave

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• What does this structure actually do?

  - by LGTrader

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

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• How do I add code automatically to a derived function in C++

  - by Ian

  I have code that's meant to manage operations on both a networked client and a server, since there is significant overlap between the two. However, there are a few functions here and there that are meant to be exclusively called by the client or server, and accidentally calling a client function on the server (or vice versa) is a significant source of bugs. To reduce these sorts of programming errors, I'm trying to tag functions so that they'll raise a ruckus if they're misused. My current solution is a simple macro at the start of each function that calls an assert if the client or server accesses members they shouldn't. However, this runs into problems when there are multiple derived instances of classes, in that I have to tag the implementation as client or server side in EVERY child class. What I'd like to be able to do is put a tag in the virtual member's signature in the base class, so that I only have to tag it once and not run into errors by forgetting to do it repeatedly. I've considered putting a check in a base class implementation and then referring to it with something like base::functionName, but that runs into the same issue as far as needing to manually add the function call to every implementation. Ideally, I'd be able to have parent versions of the function called automatically like default constructors do. Does anybody know how to achieve something like this in C++? Is there an alternate approach I should be considering? Thanks!

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• Using SMO to call Database.ExecuteNonQuery() concurrently?

  - by JimDaniel

  I have been banging my head against the wall trying to figure out how I can run update scripts concurrently against multiple databases in a single SQL Server instance using SMO. Our environments have an ever-increasing number of databases which need updating, and iterating through one at a time is becoming a problem (too slow). From what I understand SMO does not support concurrent operations, and my tests have bore that out. There seems to be shared memory at the Server object level, for things like DataReader context, keeps throwing exceptions such as "reader is already open." I apologize for not having the exact exceptions I am getting. I will try to get them and update this post. I am no expert on SMO and just feeling my way through to be honest. Not really sure I am approaching it the right way, but it's something that has to be done, or our productivity will slow to a crawl. So how would you guys do something like this? Am I using the wrong technology with SMO? All I am wanting to do is execute sql scripts against databases in a single sql server instance in parallel. Thanks for any help you can give, Daniel

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• Shrinking the transaction log of a mirrored SQL Server 2005 database

  - by Peter Di Cecco

  I've been looking all over the internet and I can't find an acceptable solution to my problem, I'm wondering if there even is a solution without a compromise... I'm not a DBA, but I'm a one man team working on a huge web site with no extra funding for extra bodies, so I'm doing the best I can. Our backup plan sucks, and I'm having a really hard time improving it. Currently, there are two servers running SQL Server 2005. I have a mirrored database (no witness) that seems to be working well. I do a full backup at noon and at midnight. These get backed up to tape by our service provider nightly, and I burn the backup files to dvd weekly to keep old records on hand. Eventually I'd like to switch to log shipping, since mirroring seems kinda pointless without a witness server. The issue is that the transaction log is growing non-stop. From the research I've done, it seems that I can't truncate a log file of a mirrored database. So how do I stop the file from growing!? Based on this web page, I tried this: USE dbname GO CHECKPOINT GO BACKUP LOG dbname TO DISK='NULL' WITH NOFORMAT, INIT, NAME = N'dbnameLog Backup', SKIP, NOREWIND, NOUNLOAD GO DBCC SHRINKFILE('dbname_Log', 2048) GO But that didn't work. Everything else I've found says I need to disable the mirror before running the backup log command in order for it to work. My Question (TL;DR) How can I shrink my transaction log file without disabling the mirror?

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• Parallel.For Batching

  - by chibacity

  Is there built-in support in the TPL for batching operations? I was recently playing with a routine to carry out character replacement on a character array which required a lookup table i.e. transliteration: for (int i = 0; i < chars.Length; i++) { char replaceChar; if (lookup.TryGetValue(chars[i], out replaceChar)) { chars[i] = replaceChar; } } I could see that this could be trivially parallelized, so jumped in with a first stab which I knew would perform worse as the tasks were too fine-grained: Parallel.For(0, chars.Length, i => { char replaceChar; if (lookup.TryGetValue(chars[i], out replaceChar)) { chars[i] = replaceChar; } }); I then reworked the algorithm to use batching so that the work could be chunked onto different threads in less fine-grained batches. This made use of threads as expected and I got some near linear speed up. I'm sure that there must be built-in support for batching in the TPL. What is the syntax, and how do I use it? const int CharBatch = 100; int charLen = chars.Length; Parallel.For(0, ((charLen / CharBatch) + 1), i => { int batchUpper = ((i + 1) * CharBatch); for (int j = i * CharBatch; j < batchUpper && j < charLen; j++) { char replaceChar; if (lookup.TryGetValue(chars[j], out replaceChar)) { chars[j] = replaceChar; } } });

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• Building "isolated" and "automatically updated" caches (java.util.List) in Java.

  - by Aidos

  Hi Guys, I am trying to write a framework which contains a lot of short-lived caches created from a long-living cache. These short-lived caches need to be able to return their entier contents, which is a clone from the original long-living cache. Effectively what I am trying to build is a level of transaction isolation for the short-lived caches. The user should be able to modify the contents of the short-lived cache, but changes to the long-living cache should not be propogated through (there is also a case where the changes should be pushed through, depending on the Cache type). I will do my best to try and explain: master-cache contains: [A,B,C,D,E,F] temporary-cache created with state [A,B,C,D,E,F] 1) temporary-cache adds item G: [A,B,C,D,E,F] 2) temporary-cache removes item B: [A,C,D,E,F] master-cache contains: [A,B,C,D,E,F] 3) master-cache adds items [X,Y,Z]: [A,B,C,D,E,F,X,Y,Z] temporary-cache contains: [A,C,D,E,F] Things get even harder when the values in the items can change and shouldn't always be updated (so I can't even share the underlying object instances, I need to use clones). I have implemented the simple approach of just creating a new instance of the List using the standard Collection constructor on ArrayList, however when you get out to about 200,000 items the system just runs out of memory. I know the value of 200,000 is excessive to iterate, but I am trying to stress my code a bit. I had thought that it might be able to somehow "proxy" the list, so the temporary-cache uses the master-cache, and stores all of it's changes (effectively a Memento for the change), however that quickly becomes a nightmare when you want to iterate the temporary-cache, or retrieve an item at a specific index. Also given that I want some modifications to the contents of the list to come through (depending on the type of the temporary-cache, whether it is "auto-update" or not) and I get completly out of my depth. Any pointers to techniques or data-structures or just general concepts to try and research will be greatly appreciated. Cheers, Aidos

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• Does .Net use Device Dependent or Device Independent Bitmaps?

  - by Brian

  When loading an image into memory, does .Net use DDB, DIB, or something else entirely? If possible, please cite your sources. I'm wondering because we currently have a classic ASP application that is using a 3rd party component to load images that is occasionally creating a “Not enough storage is available to process this command.” error. The error is very inconsistent but tends to happen on larger images (not always, but often). After resetting IIS, processing the same file again typically works just fine. After much research I have found that DDBs tend to have this problem when processing large images because they work out of video memory. Considering that we are running on a web server with an integrated video card and limited shared memory, this could certainly be our problem. We are in the early stages of converting our app to .Net and am wondering if using .Net for this might be a viable alternative to our current method which is why I am asking the question. Any advice is welcome :) but out of curiosity if nothing else, I am really hoping for an answer to the question; does .Net use DDB or DIB?

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• Why doesn't java.lang.Number implement Comparable?

  - by Julien Chastang

  Does anyone know why java.lang.Number does not implement Comparable? This means that you cannot sort Numbers with Collections.sort which seems to me a little strange. Post discussion update: Thanks for all the helpful responses. I ended up doing some more research about this topic. The simplest explanation for why java.lang.Number does not implement Comparable is rooted in mutability concerns. For a bit of review, java.lang.Number is the abstract super-type of AtomicInteger, AtomicLong, BigDecimal, BigInteger, Byte, Double, Float, Integer, Long and Short. On that list, AtomicInteger and AtomicLong to do not implement Comparable. Digging around, I discovered that it is not a good practice to implement Comparable on mutable types because the objects can change during or after comparison rendering the result of the comparison useless. Both AtomicLong and AtomicInteger are mutable. The API designers had the forethought to not have Number implement Comparable because it would have constrained implementation of future subtypes. Indeed, AtomicLong and AtomicInteger were added in Java 1.5 long after java.lang.Number was initially implemented. Apart from mutability, there are probably other considerations here too. A compareTo implementation in Number would have to promote all numeric values to BigDecimal because it is capable of accommodating all the Number sub-types. The implication of that promotion in terms of mathematics and performance is a bit unclear to me, but my intuition finds that solution kludgy.

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• Is there an x86 or x64 emulator that passes system calls back to the Windows API?

  - by Chris Lomont

  I want to emulate windows programs (not VM, true emulation) under windows. This would require the emulator to make calls back to the system APIs, but the program itself would be emulated. The reason is I want to change the opcode formats for research purposes. The process should be: Take existing program. Disassemble and then reassemble with my new opcode formats. Put the new format into the PE with a stub calling the emulator and passing the new code. The emulator would have to pass system calls from the emulated side back to windows API calls. I can do all these steps, except I need an open source emulator with the ability to pass the API calls out. I could try Bochs or QEMU, but I think I'd have to add in the system calls, which I could do if needed. I wonder if there is already something closer to what I need. I know I would have to change the instruction decoding in the emulator to match my new formats, but that is a given. Thanks.

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• Rails paginate existing array of ActiveRecord results

  - by SaoiseK

  Hello, I generally use will_paginate for the pagination in my app, but have hit a stumbler on my search feature. I'm using Thinking Sphinx for doing my full-text search, which returns results paginated. The problem I'm having is that after I've received the results from Thinking Sphinx, I need to merge them with some other results and re-order them. Once I've finished processing them I have an Array of results that is very different from the original from TS. As there could be 1000+ results in this Array Pagination is a necessity. The problem is that I can't figure out how to get will_paginate to play with an existing array. I've done some research and it seems the only solutions to this problem are from several years ago and are based around the old built-in Paginator class. The most recent one I could find that makes use of will_paginate was from devchix from mid-2007: http://www.devchix.com/2007/07/23/will_paginate-array/comment-page-1/ - I've given this a go but it doesn't seem to do anything for me. Are there any current methods for applying pagination (preferably via will_paginate) for existing arrays of AR results?

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• Java - Removing duplicates in an ArrayList

  - by Will

  I'm working on a program that uses an ArrayList to store Strings. The program prompts the user with a menu and allows the user to choose an operation to perform. Such operations are adding Strings to the List, printing the entries etc. What I want to be able to do is create a method called removeDuplicates().This method will search the ArrayList and remove any duplicated values. I want to leave one instance of the duplicated value(s) within the list. I also want this method to return the total number of duplicates removed. I've been trying to use nested loops to accomplish this but I've been running into trouble because when entries get deleted, the indexing of the ArrayList gets altered and things don't work as they should. I know conceptually what I need to do but I'm having trouble implementing this idea in code. Here is some pseudo code: start with first entry; check each subsequent entry in the list and see if it matches the first entry; remove each subsequent entry in the list that matches the first entry; after all entries have been examined, move on to the second entry; check each entry in the list and see if it matches the second entry; remove each entry in the list that matches the second entry; repeat for entry in the list Here's the code I have so far: public int removeDuplicates() { int duplicates = 0; for ( int i = 0; i < strings.size(); i++ ) { for ( int j = 0; j < strings.size(); j++ ) { if ( i == j ) { // i & j refer to same entry so do nothing } else if ( strings.get( j ).equals( strings.get( i ) ) ) { strings.remove( j ); duplicates++; } } } return duplicates; }

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• Read/Write/Find/Replace huge csv file

  - by notapipe

  I have a huge (4,5 GB) csv file.. I need to perform basic cut and paste, replace operations for some columns.. the data is pretty well organized.. the only problem is I cannot play with it with Excel because of the size (2000 rows, 550000 columns). here is some part of the data: ID,Affection,Sex,DRB1_1,DRB1_2,SENum,SEStatus,AntiCCP,RFUW,rs3094315,rs12562034,rs3934834,rs9442372,rs3737728 D0024949,0,F,0101,0401,SS,yes,?,?,A_A,A_A,G_G,G_G D0024302,0,F,0101,7,SN,yes,?,?,A_A,G_G,A_G,?_? D0023151,0,F,0101,11,SN,yes,?,?,A_A,G_G,G_G,G_G I need to remove 4th, 5th, 6th, 7th, 8th and 9th columns; I need to find every _ character from column 10 onwards and replace it with a space ( ) character; I need to replace every ? with zero (0); I need to replace every comma with a tab; I need to remove first row (that has column names; I need to replace every 0 with 1, every 1 with 2 and every ? with 0 in 2nd column; I need to replace F with 2, M with 1 and ? with 0 in 3rd column; so that in the resulting file the output reads: D0024949 1 2 A A A A G G G G D0024302 1 2 A A G G A G 0 0 D0023151 1 2 A A G G G G G G (both input and output should read one line per row, ne extra blank row) Is there a memory efficient way of doing that with java(and I need a code to do that) or a usable tool for playing with this large data so that I can easily apply Excel functionality..

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• changing asp .net web service namespace when already in productive state

  - by eloQ

  by some unfortunate events we published a web service with the tempuri-namespace a couple of months ago and no one did notice (not in our company, not the companies connecting to the web service) even though it's live since that time and lots of companies (~25 i guess) already access this web service. now i'm thinking of correcting that mistake and have the namespace fixed to a proper value. the only problem is: as soon as we would do it, all the programs and services connected to this web service would stop working. i can't really allow that to happen. is there any way to fix the namespace for future purpose or to have the web service operate under two namespaces as one web service? any tip at all what i could do to get rid of the tempuri-namespace and have it fixed without needing to synchronize the change with all the external companies? i'm all out of ideas, so any help would be much appreciated! thanks! I hope this question is alright here, first time user, found this through using search engines on my research and found tempuri.org related posts, just not the right one..

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• Entity Framework autoincrement key

  - by Tommy Ong

  I'm facing an issue of duplicated incremental field on a concurrency scenario. I'm using EF as the ORM tool, attempting to insert an entity with a field that acts as a incremental INT field. Basically this field is called "SequenceNumber", where each new record before insert, will read the database using MAX to get the last SequenceNumber, append +1 to it, and saves the changes. Between the getting of last SequenceNumber and Saving, that's where the concurrency is happening. I'm not using ID for SequenceNumber as it is not a unique constraint, and may reset on certain conditions such as monthly, yearly, etc. InvoiceNumber | SequenceNumber | DateCreated INV00001_08_14 | 1 | 25/08/2014 INV00001_08_14 | 1 | 25/08/2014 <= (concurrency is creating two SeqNo 1) INV00002_08_14 | 2 | 25/08/2014 INV00003_08_14 | 3 | 26/08/2014 INV00004_08_14 | 4 | 27/08/2014 INV00005_08_14 | 5 | 29/08/2014 INV00001_09_14 | 1 | 01/09/2014 <= (sequence number reset) Invoice number is formatted based on the SequenceNumber. After some research I've ended up with these possible solutions, but wanna know the best practice 1) Optimistic Concurrency, locking the table from any reads until the current transaction is completed (not fancy of this idea as I guess performance will be of a great impact?) 2) Create a Stored Procedure solely for this purpose, does select and insert on a single statement as such concurrency is at minimum (would prefer a EF based approach if possible)

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• HTTP POST with URL query parameters -- good idea or not?

  - by Steven Huwig

  I'm designing an API to go over HTTP and I am wondering if using the HTTP POST command, but with URL query parameters only and no request body, is a good way to go. Considerations: "Good Web design" requires non-idempotent actions to be sent via POST. This is a non-idempotent action. It is easier to develop and debug this app when the request parameters are present in the URL. The API is not intended for widespread use. It seems like making a POST request with no body will take a bit more work, e.g. a Content-Length: 0 header must be explicitly added. It also seems to me that a POST with no body is a bit counter to most developer's and HTTP frameworks' expectations. Are there any more pitfalls or advantages to sending parameters on a POST request via the URL query rather than the request body? Edit: The reason this is under consideration is that the operations are not idempotent and have side effects other than retrieval. See the HTTP spec: In particular, the convention has been established that the GET and HEAD methods SHOULD NOT have the significance of taking an action other than retrieval. These methods ought to be considered "safe". This allows user agents to represent other methods, such as POST, PUT and DELETE, in a special way, so that the user is made aware of the fact that a possibly unsafe action is being requested. ... Methods can also have the property of "idempotence" in that (aside from error or expiration issues) the side-effects of N 0 identical requests is the same as for a single request. The methods GET, HEAD, PUT and DELETE share this property. Also, the methods OPTIONS and TRACE SHOULD NOT have side effects, and so are inherently idempotent.

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• ColdFusion Session issue - multiple users behind one proxy IP -- cftoken and cfid seems to be shared

  - by smoothoperator

  Hi Everyone, I have an application that uses coldfusion's session management (instead of the J2EE) session management. We have one client, who has recently switched their company's traffic to us to come viaa proxy server in their network. So, to our Coldfusion server, it appears that all traffic is coming from this one IP Address, for all of the accounts of this one company.. Of the session variables, Part 1 is kept in a cflock, and Part 2 is kept in editable session variables. I may be misundestanding, but we have done it this way as we modify some values as needed throughout the application's usage. We are now running into an issue of this client having their session variables mixed up (?). We have one case where we set a timestamp.. and when it comes time to look it up, it's empty. From the looks of it this is happening because of another user on the same token. My initial thoughts are to look into modifying our existing session management to somehow generate a unique cftoken/cfid, or to start using jsession_ID, if this solves the problem at all. I have done some basic research on this issue and couldn't find anything similar, so I thought I'd ask here. Thanks!

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• MS SQL - Multi-Column substring matching

  - by hamlin11

  One of my clients is hooked on multi-column substring matching. I understand that Contains and FreeText search for words (and at least in the case of Contains, word prefixes). However, based upon my understanding of this MSDN book, neither of these nor their variants are capable of searching substrings. I have used LIKE rather extensively (Select * from A where A.B Like '%substr%') Sample table A: ID | Col1 | Col2 | Col3 | ------------------------------------- 1 | oklahoma | colorado | Utah | 2 | arkansas | colorado | oklahoma | 3 | florida | michigan | florida | ------------------------------------- The following code will give us row 1 and row 2: select * from A where Col1 like '%klah%' or Col2 like '%klah%' or Col3 like '%klah%' This is rather ugly, probably slow, and I just don't like it very much. Probably because the implementations that I'm dealing with have 10+ columns that need searched. The following may be a slight improvement as code readability goes, but as far as performance, we're still in the same ball park. select * from A where (Col1 + ' ' + Col2 + ' ' + Col3) like '%klah%' I have thought about simply adding insert, update, and delete triggers that simply add the concatenated version of the above columns into a separate table that shadows this table. Sample Shadow_Table: ID | searchtext | --------------------------------- 1 | oklahoma colorado Utah | 2 | arkansas colorado oklahoma | 3 | florida michigan florida | --------------------------------- This would allow us to perform the following query to search for '%klah%' select * from Shadow_Table where searchtext like '%klah%' I really don't like having to remember that this shadow table exists and that I'm supposed to use it when I am performing multi-column substring matching, but it probably yields pretty quick reads at the expense of write and storage space. My gut feeling tells me there there is an existing solution built into SQL Server 2008. However, I don't seem to be able to find anything other than research papers on the subject. Any help would be appreciated.

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