Search Results

Search found 7722 results on 309 pages for 'pitfalls to avoid'.

Page 192/309 | < Previous Page | 188 189 190 191 192 193 194 195 196 197 198 199  | Next Page >

  • Importing a spreadsheet, but having trouble.

    - by Chris Phelps
    I have a form that allows a user to import a spreadsheet. This spreadsheet is generally static when it comes to column headers, but now the users want to be able to include an optional column (called Notes). My code crashes when I try to read the column from the spreadsheet if it doesn't exist. Dim objCommand As New OleDbCommand() objCommand = ExcelConnection() 'function that opens spreadsheet and returns objCommand Dim reader As OleDbDataReader reader = objCommand.ExecuteReader() While reader.Read() Dim Employee As String = Convert.ToString(reader("User")) Dim SerialNUM As String = Convert.ToString(reader("serialno")) **Dim Notes As String = Convert.ToString(reader("notes"))** If the spreadsheet contains a Notes column, all goes well. If not, crash. How can I check to see if the Notes column exists in the spreadsheet to avoid the crash?

    Read the article

  • Rails + simple role system through associative table

    - by user202411
    So I have the Ninja model which has many Hovercrafts through ninja_hovercrafts (which stores the ninja_id and the hovercraft_id). It is of my understanding that this kind of arrangement should be set in a way that the associative table stores only enough information to bind two different classes. But I'd like to use the associative table to work as a very streamlined authorization hub on my application. So i'd also like this table to inform my system if this binding makes the ninja the pilot or co-pilot of a given hovercraft, through a "role" field in the table. My questions are: Is this ugly? Is this normal? Are there methods built into rails that would help me to automagically create Ninjas and Hovercrafts associations WITH the role? For exemple, could I have a nested form to create both ninjas and hcs in a way that the role field in ninjas_hovercrafts would be also filled? If managing my application roles this way isn't a good idea, whats the non-resource heavy alternative (my app is being designed trying to avoid scalability problems such as excessive joins, includes, etc) thank you

    Read the article

  • C# cross class enum visibility - Possible?

    - by 537mfb
    so i have a class ClassA that contains an enum MyEnum, and a class ClassB that references that class (different Projects) and so in ClassB i have a using ClassA; clause and i can access that enum using something like MyEnum value = MyEnum.EnumValue; Now on a third project i have my Windows form and it has a clause like using ClassB; Now what can i add in ClassB to acess that enum on my windows Form? Is it even Possible? i would like to avoid having to add ClassA to my form just to access an enum. The idea is that ClassB is sort of a manager between my form and the functionality in ClassA - but i would like to get access to that enum as it makes a lot of tasks easier

    Read the article

  • static images aren't caching with php-generated page

    - by scootklein
    Our website was just converted to being generated by mod_rewrite and php scripts. Images aren't caching in browsers when they seemingly should be. All images follow format: <img src="/images/header.png" /> I must avoid the script completely caching because the PHP parser needs to handle each page dynamically on each request; however, the download overhead of the large images is cumbersome on every single page load. I would ideally provide headers for "Cache-Control: no-cache, must-revalidate" and "Expires: some_date_in_the_past" to force revalidation of the PHP script. Why isn't the browser caching static images with consistent href values across all pages?

    Read the article

  • Aren't passwords written in inputbox vulnerable through a stack trace ?

    - by loursonwinny
    Hello, I am not a guru of the stack tracing, at all. I even don't know how to get some. Anyway, I am wondering if entering a password entered in an inputbox is safe. Can't it be retrieved by getting a stack trace ? A password entered that way will be found in many places : Caption property of the TEdit Result of the function which creates the inputbox probably, a variable that stores the Result of the InputBox Command etc... If the answer is "yes, it is a vulnerability", then my world collapses :p. What can be done to avoid that vulnerability hole ? NOTE : The InputBox is an example but it can be with a "homebrewed" login prompt. InputBox is a Delphi command but I haven't tagged the question with the Delphi tag because I suppose that the question concerns any language. Thanks for reading

    Read the article

  • Copy of Access mdb database being updated by live database

    - by James
    I'm trying to compute statistics for data held in an Access .mdb database. In order to avoid interfering with the live database, I'm working from a copy which I made by simply using copy-paste in Windows Explorer. The copy resides in the same directory, but with a different name. I'm using R and RODBC to connect to the copy of the file. The strange thing is that new data that is being updated on the original live database is appearing in my queries. This is despite the file timestamps of the copy not changing at all. It is also causing some slowdown in the live database. My understanding is that the .mdb files are standalone, or is this not the case? Should I have copied the database in a different way?

    Read the article

  • SQL Server db_owner

    - by andrew007
    Hi, in my SQL2008 I have a user which is in the "db_datareader", "db_datawriter" and "db_ddladmin" DB roles, however when he tries to modify a table with SSMS he receives a message saying: You are not logged in as the database owner or system administrator. You might not be able to save changes to tables that you do not own. Of course, I would like to avoid such message, but until now I did find the way... Therefore, I try to modify the user by adding him to the "db_owner" role, and of course I do not have the message above. My question is: Is it possible to keep the user in the "db_owner" role, but deny some actions like alter user or ? I try "alter any user" securable on DB level, but it does not work... THANKS!

    Read the article

  • reading csv file without for

    - by Abruzzo Forte e Gentile
    Hi All I need to read a CSV file in python. Since for last row I receive a 'NULL byte' error I would like to avoid using for keyword but the while. Do you know how to do that? reader = csv.reader( file ) for row in reader # I have an error at this line # do whatever with row I want to substitute the for-loop with a while-loop so that I can check if the row is NULL or not. What is the function for reading a single row in the CSV module? Thanks Thanks p.S. below the traceback Traceback (most recent call last): File "FetchNeuro_TodayTrades.py", line 189, in for row in reader: _csv.Error: line contains NULL byte

    Read the article

  • scala jrebel superclass change

    - by coubeatczech
    hi, I'm using JRebel with Scala and I'm quite frequently experiencing the need for restart of server due to the fact that JRebel is unable to load a class if the superclass was changed. This is done mainly when I change anonymous functions as I can deduce from the JRebel error desription: Class 'mypackage.NewBook$$anonfun$2' superclass was changed from 'scala.runtime.AbstractFunction1' to 'scala.runtime.AbstractFunction2' and could not be reloaded. Is there any way, how can I design my code to avoid this? Does scala compiler take the functions, numbers them from one as they appear in source code?

    Read the article

  • Use HTML markup into web.config file

    - by stighy
    Hi, i've to display a messagge in my homepage (default.aspx) different for each "installation" of my web app. i would like to avoid to make a call to database to show this message.. so i've thougth to use web.config to store something like this <add key="WelcomeString" value="lorem ipsus <b>doloret sit amen</b>" /> But i've noticed i can't use html markup into web.config ... Is there a better approach ? Or is there a way to insert html markup into web.config ? Thank you again stack overflow guru's... i'm learning from you a lot of things !

    Read the article

  • One configuration per domain name on the same application. How to easily access config values from m

    - by Aymeric
    Hi, I run a Ruby on Rails website that have multiple domain names. I have a "Website" table in the database that stores the configuration values related to each domain name: Website - domain - name - tagline - admin_email - etc... At the moment, I load the website object at the start of each request (before_filter) in my ApplicationController: @website = Website.find_by_domain(request.host) The problem is when I need to access the @website object from my models methods. I would like to avoid to have to pass @website everywhere. The best solution would be to have something similar to APP_CONFIG but per domain name. def sample_model_property - - "#{@website.name} is a great website!" end How would you do it?

    Read the article

  • Java: Reflection against casting when you know superclass

    - by Ema
    I don't know exactly how to define my doubt so please be patient if the question has already been asked. Let's say I have to dinamically instantiate an object. This object will surely be instance of a subclass of a known, immutable class A. I can obtain dinamically the specific implementation class. Would it be better to use reflection exactly as if I didn't know anything about the target class, or would it be preferrable/possible to do something like: A obj = (Class.forName("com.package.Sub-A")) new A(); where Sub-A extends A ? The purpose would be to avoid reflection overhead times... Thank you in advance.

    Read the article

  • How to efficiently implement a blocking call with Rails, while letting the client wait for the reply

    - by Kyle Heironimus
    We have a web service written in Rails. The API is published and we cannot change it. Our app communicates with a remote web service that sometimes hangs or takes several seconds to reply. Client -> Our Web Service -> Remote Web Service Currently, if the remote web service hangs for 5 seconds, one of our rails processes on our web service also hangs with it, which is what we need to avoid. I've seen things such as mod-x-sendfile, modporter, and delayed jobs, but the best I can tell, they all assume the client is not waiting for an answer. Since the API is already established, we cannot tell the client "I'm attempting to do what you want, check back later for the answer." The best option we have come up with so far is to add a second, non-rails web server running eventmachine to process these particular calls. Is there a better way?

    Read the article

  • C++ containers on classes, returning pointers

    - by otneil
    Hello, I'm having some trouble to find the best way to accomplish what I have in mind due to my inexperience. I have a class where I need to a vector of objects. So my first question will be: is there any problem having this: vector< AnyType container* and then on the constructor initialize it with new (and deleting it on the destructor)? Another question is: if this vector is going to store objects, shouldn't it be more like vector< AnyTipe* so they could be dynamically created? In that case how would I return an object from a method and how to avoid memory leaks (trying to use only STL)?

    Read the article

  • PHP => Alternative to session data?

    - by Armz
    i have a Web Application where Cookies and Session are both important. Since the Web Application is load balanced on different server, i am looking for suggestions to Alternative Store for the Session data that all server will be able to access. Some sessions could live up to severals days. The solutions that come to my mind: - Native PHP Sessions (this is the one i want to stop using) - MySQL Database - Serialize and write to a file (i want to avoid this, for performances) - Memcache (however it could become very big or older data getting knocked out) Thanks in advance!

    Read the article

  • Hibernate Unit tests - Reset schema

    - by Marco
    Hi, I'm testing the CRUD operations of my DAOs in JUnit tests. When i execute the single test, Hibernate always resets the schema and populates the DB in a known state. But when i execute multiple tests in a row, Hibernate resets the schema once, and then the data is accumulated during the execution of the tests. This is an unexpected behavior, so I'd like to add in the @Before method of the tests a function that explicitly resets the schema to avoid the pesistence of side data created by previous tests during the execution chain. Any tips? Thanks

    Read the article

  • Twitter search c#

    - by Lily
    Hi, I have implemented a method which manually scrapes the Search Twitter page and gets the tweets on different pages. But since there is a fast refresh rate, the method triggers an exception. Therefore I have decided to use TweetSharp API instead var search = FluentTwitter.CreateRequest() .AuthenticateAs(TWITTER_USERNAME, TWITTER_PASSWORD) .Users().SearchFor("dumbledore"); var result = search.Request(); var users = result.AsUsers(); this code was on the site. Does anyone know how I can avoid giving my credentials and retrieve from all users and not just the ones I have as friends? Thanks!

    Read the article

  • JavaScript's Associative Array / Object can't be read in functions

    - by Matrym
    At the very beginning of the javascript file, I have: var lbp = {}; lbp.defaults = { minLength: 40 }; I can successfully alert it afterwards, with: alert(lbp.defaults.minLength); But as soon as I put it inside a function, when I alert, I get "Undefined". What gives, and how do I avoid this? Is it absolutely necessary to pass this variable into each function, for example, by doing: function(lbp) { alert(lbp.defaults.minLength); } I would have thought that defining it first, it would attain global scope and not be required to be passed in? Thanks in advance for enlightening me :)

    Read the article

  • bitfield mask calculation macro

    - by Aidan Cully
    We have a set of C macros, here, for using the preprocessor to do bitfield operations, and we run into warnings when attempting to use these macros in visual studio. The problem can be demonstrated very easily: #define BITFIELD_WIDTHMASK(Width) \ ((Width) >= 32 ? ~0x0ul : (1ul << (Width)) - 1) unsigned long foo(void) { return BITFIELD_WIDTHMASK(32); } Compiling this with MSVC yields the warning: test.c(12) : warning C4293: '<<' : shift count negative or too big, undefined behavior This isn't a behavior problem - the << operator won't be used in this case, and that should be detected at compile time. But does anyone have any suggestions about how to rewrite the macro to avoid the warning? Or, failing that, how to redesign the macro interface for this? Thanks in advance

    Read the article

  • NHibernate SchemaUpdate adding existing foreign keys again?

    - by afsharm
    I'm using SchemaUpdate to synchronize my hbms with existing database. Database has recently created based on hbms and is completely up-to-date. But SchemaUpdate generates all foreign key constraints again. For example suppose you have Student and Teacher. Student has association to Teacher with name ArtTeacher. ArtTeacher is a foreign key from Student to Teacher. Suppose database is up-to-date and currently holde Student, Teacher and their foreign key relation. So HBM and Database are equivalent. Know SchemaUpdate must not do anything but when I see its generated scripts, it re-produce that foreign key again. Why this happens? Is there any way to avoid it?

    Read the article

  • What are the correct group and artifact id's for jee 5 and 6 artifacts?

    - by Pangea
    So far we have been manually downloading the jars and deploying to our maven repo with custom group/artifact id's. I would like to avoid that. So my question is What are the correct group and artifact id's for jee 5 and 6 artifacts? I'd like to get the names at JSR level (for example I doesn't need the ids for jee 6 uber jar but individual api's like jsr 330 etc) Which is the CORRECT repo to get these from? Does Oracle host there in their own repos?

    Read the article

  • Is window.location.href = 'some_page.html' followed by search engines?

    - by Arkaaito
    Currently our website uses links to allow the user to change their locale. The problem with this is that you get a lot of random outlinks from each page on the site to... the same page, in other languages. When a search engine traverses this, it gets an excessively complex view of the site. We were going to change it to a form post to avoid this. However, it seems to me that we should just be able to change it to an onclick="window.location.href='change_my_language.php'" rather than an href="change_my_language.php". Am I right? Or do the major search engines scan for and follow this sort of thing nowadays?

    Read the article

  • Ways to make your WCF services compatible with non-.NET consumers

    - by Mayo
    I'm working on adding a WCF services layer to my existing .NET application. This layer will be hosted in IIS and will be consumed by a variety of UIs, at least one of which will not use Microsoft technologies. I can make a Web service in WCF that is consumed by my .NET application. However, I'm concerned about things that work in the .NET world but not with other technologies. For example, simply throwing an exception from my WCF service works fine in .NET. But according to this article, one should approach exception handling with fault contracts to ensure compatibility with non-.NET consumers. The author labels this lack of foresight as The Fallacy of the .NET-Only World. Does anyone have any high level suggestions or links to articles that cover interoperability between WCF and non-.NET consumers? I realize I'm potentially working against the YAGNI principle. I'm only really looking to avoid things that will be incredibly difficult to overcome later when the developers of the non-.NET consumer report problems to me.

    Read the article

  • Can git switch branch without the modification

    - by hguser
    I have a project which have completed the basic models(at master), then I commit them. Then I create two branchs user and product using: git checkout -b user git checkout -b product git checkout user Then I add the codes in the user branch, but I found that I have to make some changes for the basic models. Then I switch to master: git checkout master But I found that the modification I made in the user branch is visible in the working directory now. How to avoid this? Since the change to master and modification will be frequency.

    Read the article

  • Problem with foreach loop and $_GET

    - by phpExe
    I have a very simple foreach loop foreach($tv as $id => $channel) { $ID = $_GET['ID']; if($ID == $id){$class = "currentt";} echo '<a href="http://www.mysite.com/tst.php?ID='.$id.'" class="'.$class.'">'.$channel.'</a><br>'; } With url query, with every click the current class repeated. How can avoid this? Thanks alot.

    Read the article

< Previous Page | 188 189 190 191 192 193 194 195 196 197 198 199  | Next Page >