Search Results

Search found 13867 results on 555 pages for 'avoid learning'.

Page 384/555 | < Previous Page | 380 381 382 383 384 385 386 387 388 389 390 391  | Next Page >

• Side effects of reordering columns in PostgreSQL

  - by Summer

  I sometimes re-order the columns in my Postgres DB. Since Postgres can only add columns at the end of tables, I end up re-ordering by adding new columns at the end of the table, setting them equal to existing columns, and then dropping the original columns. My question is: what does PostgreSQL do with the memory that's freed by dropped columns? Does it automatically re-use the memory, so a single record consumes the same amount of space as it did beforehand? But that would require a re-write of the whole table, so to avoid that, does it just keep a bunch of blank space around in each record? Thanks! ~S

  Read the article

• How to write a jUnit test for this class?

  - by flash

  Hi, I would like to know what's the best approach to test the method "pushEvent()" in the following class with a jUnit test. My problem is, that the private method "callWebsite()" always requires a connection to the network. How can I avoid this requirement or refactor my class that I can test it without a connection to the network? class MyClass { public String pushEvent (Event event) { //do something here String url = constructURL (event); //construct the website url String response = callWebsite (url); return response; } private String callWebsite (String url) { try { URL requestURL = new URL (url); HttpURLConnection connection = null; connection = (HttpURLConnection) requestURL.openConnection (); String responseMessage = responseParser.getResponseMessage (connection); return responseMessage; } catch (MalformedURLException e) { e.printStackTrace (); return e.getMessage (); } catch (IOException e) { e.printStackTrace (); return e.getMessage (); } } }

  Read the article

• text between lines in css

  - by Tom91136

  in CSS, how can i do something like: ---Item--- with the dash connected like a line? i thought of : border-bottom: 3px solid #000; but then i can't move the line upward plus the line would be behind the text, not surrounding the text my HTML <ul> <li class="sub-menu-item" ><a href="#">FACULTY&STAFF</a></li> </ul> (if possible, i would like to avoid touching the HTML) is all the above possible via css or should i just use an image after all?

  Read the article

• Create controls dynamically

  - by Afnan

  I want to know if this is possible in c# winform. create control when ever button is pressed and place it at given location. I think it is possible like this private TextBox txtBox = new TextBox(); private Button btnAdd = new Button(); private ListBox lstBox = new ListBox(); private CheckBox chkBox = new CheckBox(); private Label lblCount = new Label(); but the problem lies when ever button is pressed same name controls are created.How to avoid that

  Read the article

• How do I implement .net plugins without using AppDomains?

  - by Abtin Forouzandeh

  Problem statement: Implement a plug-in system that allows the associated assemblies to be overwritten (avoid file locking). In .Net, specific assemblies may not be unloaded, only entire AppDomains may be unloaded. I'm posting this because when I was trying to solve the problem, every solution made reference to using multiple AppDomains. Multiple AppDomains are very hard to implement correctly, even when architected at the start of a project. Also, AppDomains didn't work for me because I needed to transfer Type across domains as a setting for Speech Server worfklow's InvokeWorkflow activity. Unfortunately, sending a type across domains causes the assembly to be injected into the local AppDomain. Also, this is relevant to IIS. IIS has a Shadow Copy setting that allows an executing assembly to be overwritten while its loaded into memory. The problem is that (at least under XP, didnt test on production 2003 servers) when you programmatically load an assembly, the shadow copy doesnt work (because you are loading the DLL, not IIS).

  Read the article

• How to do MVC form url formatting?

  - by dqhendricks

  I am using PHP. I want to create an MVC setup from scratch to learn more about how MVC works. I want to use clean urls with slashes as delimiters for the arguments. How do people do this when it comes to GET method forms? Or do people avoid GET method forms all together? As of right now the ways I can imagine are: Don't use GET method forms (although this makes it harder to let users bookmark/link in some cases). Use AJAX instead of form submission (although what do you do for SEO and JS disablers?). Have page submit to itself with post method, then reform the post vars into an url, then rerout to that url using headers (seems like wasted resources). Any suggestions or suggested reading welcome.

  Read the article

• Python Library installation

  - by MacPython

  Hi everybody I have two questions regarding python libraries: I would like to know if there is something like a "super" python library which lets me install ALL or at least all scientific useful python libraries, which I can install once and then I have all I need. There is a number of annoying problems when installing different libraries (pythonpath, cant import because it is not installed BUT it is installed). Is there any good documentation about common installation errors and how to avoid them. If there is no total solution I would be interested in numpy, scipy, matplotlib, PIL Thanks a lot for the attention and help Best Z

  Read the article

• ASP.NET auto submits form with only one textbox

  - by MartinHN

  Hi, look at this code: <%@ Page Language="C#" AutoEventWireup="true" CodeFile="test.aspx.cs" Inherits="test" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title>Untitled Page</title> </head> <body> <form id="form1" runat="server"> <input type="text" /> </form> </body> </html> When I hit the enter key, when the input box has focus - the form submits. If I add another input box it doesn't submit. How can I avoid the auto submit when there's only one input box?

  Read the article

• What do gurus say about Requirements Traceability Matrix?

  - by Jaywalker

  Our organization is at CMMI Level 2, and as part of the requirements of the level, we have to maintain an RTM which more or less contains the following entries for each requirement: Requirement Description Reference Section Functional Specification Document Reference Section Design Document Reference Section Test Cases Document Now, this might be an overkill for a small project. But more importantly, this could be a nightmare to maintain when the requirements/ features keep changing, and documents have to be constantly updated. What do the gurus say about this? Should one avoid such level of documentation or are there any tools to manage when a "change" out dates so many artifacts? And by using the term 'gurus', I am not talking of coding champs; rather people like Steve McConnel or others who have worked on commercial projects of medium to large scale. Quotes/ book references/ articles will suit me. EDIT: It's not just requirements that change. Design Document can change; well, even test cases may change.

  Read the article

• Using Report (Reporting Services) parameter values in ASP.NET page

  - by noup

  I have a report (Reporting Services) integrated into an ASP.NET that shows dropdownlists to select report parameter values. The dropdownlists are populated using direct database selects, though I see the report RDL files do contain the paramter values and datasets as defined in the report designer. Is it possible to obtain the report parameters "available values" in ASP.NET to populate the dropdownlists? This would avoid some code duplication. Update If the parameter doesn't use a query for available values, the following works: foreach (ValidValue value in this.ReportViewerControl.ServerReport.GetParameters()["myParameter"].ValidValues) { this.DropDownListControl.Items.Add(new ListItem(value.Label, value.Value)); } Still haven't found a way to access report datasets though...

  Read the article

• MySQL foreign key constraints, cascade delete

  - by Cudos

  Hello. I want to use foreign keys to keep the integrity and avoid orphans (I already use innoDB). How do I make a SQL statment that DELETE ON CASCADE? Secondly, that using DELETE ON CASCADE. E.g. if I delete a category then it would delete products related to that category even though there are other categories related to those products. The pivot table "categories_products" creates a many-to-many relationship between the two other tables. categories - id (INT) - name (VARCHAR 255) products - id - name - price categories_products - categories_id - products_id

  Read the article

• AS3: creating a class with multiple and optional parameters?

  - by redconservatory

  I'm creating a slideshow where each slide can have: - a video or a still - 1 audio track or many (up to 3) - 1 button or many (up to 3) I was thinking that each slide can be it's own object, and then I would pass the video, audio, buttons, etc., into it as parameters: package { import flash.media.Video; public class Section { public function Section (video:Video, still:myPhotoClass, audiotrack:Sound, button:myButtonClass) { // can have video OR a still // can have 1 audio track or several // can have 1 button or more } } I'm not sure how to go about approaching this since there can be multiples of certain items (audio, buttons) and also two items are sort-of-optional in the sense that there can be ONE or the OTHER (video/still). For example, is this something that I should just avoid passing as parameters altogether, using a different approach (getters/setters, maybe)?

  Read the article

• Remove .php extension (explicitly written) for friendly URL

  - by miquel

  htaccess to remove the .php extension of my site's files. RewriteEngine on RewriteBase / RewriteCond %{SCRIPT_FILENAME} !-d RewriteCond %{SCRIPT_FILENAME} !-f RewriteRule ^(.*)$ $1.php [L,QSA] Now, if I go to my site www.mysite.com/home works fine, it redirects to home.php but the URL is still friendly. But if I write this URL: www.mysite.com/home.php The home.php is served, and the URL is not friendly. How can I avoid this behavior? I want that if the user writes www.mysite.com/home.php, the URL displayed in the URL bar be www.mysite.com/home

  Read the article

• How to sanely read and dump structs to disk when some fields are pointers?

  - by bp

  Hello, I'm writing a FUSE plugin in C. I'm keeping track of data structures in the filesystem through structs like: typedef struct { block_number_t inode; filename_t filename; //char[SOME_SIZE] some_other_field_t other_field; } fs_directory_table_item_t; Obviously, I have to read (write) these structs from (to) disk at some point. I could treat the struct as a sequence of bytes and do something like this: read(disk_fd, directory_table_item, sizeof(fs_directory_table_item_t)); ...except that cannot possibly work as filename is actually a pointer to the char array. I'd really like to avoid having to write code like: read(disk_df, *directory_table_item.inode, sizeof(block_number_t)); read(disk_df, directory_table_item.filename, sizeof(filename_t)); read(disk_df, *directory_table_item.other_field, sizeof(some_other_field_t)); ...for each struct in the code, because I'd have to replicate code and changes in no less than three different places (definition, reading, writing). Any DRYer but still maintainable ideas?

  Read the article

• How to prevent UI from freezing during lengthy process?

  - by OverTheRainbow

  Hello, I need to write a VB.Net 2008 applet to go through all the fixed-drives looking for some files. If I put the code in ButtonClick(), the UI freezes until the code is done: Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click 'TODO Find way to avoid freezing UI while scanning fixed drives Dim drive As DriveInfo Dim filelist As Collections.ObjectModel.ReadOnlyCollection(Of String) Dim filepath As String For Each drive In DriveInfo.GetDrives() If drive.DriveType = DriveType.Fixed Then filelist = My.Computer.FileSystem.GetFiles(drive.ToString, FileIO.SearchOption.SearchAllSubDirectories, "MyFiles.*") For Each filepath In filelist 'Do stuff Next filepath End If Next drive End Sub Google returned information on a BackGroundWorker control: Is this the right/way to solve this issue? If not, what solution would you recommend, possibly with a really simple example? FWIW, I read that Application.DoEvents() is a left-over from VBClassic and should be avoided. Thank you.

  Read the article

• ASP.NET single quotes are converted to &#39;

  - by Monty

  Note: Most probably this will be a double question, but since I haven't found a clear answer, I'm asking it anyway. In ASP.NET I'd like to add some JavaScript to the onclick event of a CheckBox. I've simplified the case to this: <asp:CheckBox ID="TestCheckBox" runat="server" onclick="alert('test');" Text="Test" /> The resulting HTML is as follows: <input id="MainContainer_TestCheckBox" type="checkbox" name="ctl00$MainContainer$TestCheckBox" onclick="alert(&#39;test&#39;);" /><label for="MainContainer_TestCheckBox">Test</label> What particularly bothers me is that a single quote 'automatically' gets converted into '&#39;'. If I omit the onclick in the markup and assign it in Page_Load, the exact same results show in the HTML. protected void Page_Load(object sender, EventArgs e) { this.TestCheckBox.Attributes["onclick"] = "alert('test');"; } Anyone got a clue about what's happening? Or how to fix/ avoid it?

  Read the article

• How to suppress error messages in rpy2

  - by Björn

  Hello! The following code does not work. It seems that the R warning message raises a python error. # enable use of python objects in rpy2 import rpy2.robjects.numpy2ri import numpy as np from rpy2.robjects import r # create an example array a = np.array([[5,2,5],[3,7,8]]) # this line leads to a warning message, which in turn raises an # error message if run within a script. result = r['chisq.test'](a) Running that code example in ipython works, however, running it inside a script raises the errorTypeError: 'module' object is unsubscriptable. I assume this is due to the warning message. What is the best way to avoid this problem? Thanks in advance!

  Read the article

• Fast exchange of data between unmanaged code and managed code

  - by vizcaynot

  Hello: Without using p/invoke, from a C++/CLI I have succeeded in integrating various methods of a DLL library from a third party built in C. One of these methods retrieves information from a database and stores it in different structures. The C++/CLI program I wrote reads those structures and stores them in a List<, which is then returned to the corresponding reading and use of an application programmed completely in C#. I understand that the double handling of data (first, filling in several structures and then, filling all of these structures into a list<) may generate an unnecessary overload, at which point I wish C++/CLI had the keyword "yield". Depending on the above scenario, do you have recommendations to avoid or reduce this overload? Thanks.

  Read the article

• C++ Forward declaration for virtual function

  - by Gokul

  Hi, I have a class hierarchy and i am writing a virtual function in it. Say there are three classes class A { virtual A* test(); }; ( File A.h ) class B : public A { virtual C* test(); }; ( File B.h ) class C : public A {}; ( File C.h ) Now is it possible for me to avoid including C.h in B.h, by doing some kind of forward declaration saying that C is a sub-class of A? Thanks, Gokul.

  Read the article

• Is there such a thing as a converter from php to html?

  - by 0plus1

  Don't think that I'm mad, I understand how php works! That being said. I develop personal website and I usually take advantage of php to avoid repetion during the development phase nothing truly dynamic, only includes for the menus, a couple of foreach and the likes. When the development phase ends I need to give the website in html files to the client. Is there a tool (crawler?) that can do this for me instead of visiting each page and saving the interpreted html?

  Read the article

• ASP.NET - DropDown DataBinding (Rebind?)

  - by Bob Fincheimer

  I have a drop down which has a method which binds data to it: dropDown.Items.Clear() dropDown.AppendDataBoundItems = True Select Case selType Case SelectionTypes.Empty dropDown.Items.Insert(0, New ListItem("", "")) Case SelectionTypes.Any dropDown.Items.Insert(0, New ListItem("ANY", "")) Case SelectionTypes.Select dropDown.Items.Insert(0, New ListItem("Select One", "")) End Select BindDropDown(val) The BindDropDown method simply sets the datasource, datakeyname, datavaluename, and then databinds the data. For a reason which I cannot avoid, I MUST call this method twice sometimes. When it is called twice, All of the databound items show up two times, but the top item (the one I manually insert) is there only once. Is ASP doing something wierd when i databind twice even though i clear the list between? Or does it have to do something with the viewstate/controlstate? EDIT__ The entire page, and this control has EnableViewState="false" EDIT___ The dropdown is inside a form view. After the selected value is set I have to rebind the dropdown just in case the selected value is not there [because it is an inactive user]. After this, the formview duplicates the databound items.

  Read the article

• Heavy use of templates for mobile platforms

  - by Chris P. Bacon

  I've been flicking through the book Modern C++ Design by Andrei Alexandrescu and it seems interesting stuff. However it makes very extensive use of templates and I would like to find out if this should be avoided if using C++ for mobile platform development (Brew MP, WebOS, iOS etc.) due to size considerations. In Symbian OS C++ the standard use of templates is discouraged, the Symbian OS itself uses them but using an idiom known as thin templates where the underlying implementation is done in a C style using void* pointers with a thin template layered on top of this to achieve type safety. The reason they use this idiom as opposed to regular use of templates is specifically to avoid code bloating. So what are opinions (or facts) on the use of templates when developing applications for mobile platforms.

  Read the article

• SQL query not taking values more than 2100

  - by user175084

  SELECT MachineID, MachineName, count(ID) as Total, sum(Size) as TotalSize FROM Files join Machines on Files.MachineID = Machines.MachineID Where Files.MachineID In(sql.Append(string.Format("@MachineId{0}", i)); group by Files.MachineID,MachineName now when the machinId count is less than 2100 the query is performed and if it machines go above 2100 an error is thrown Error: The incoming tabular data stream (TDS) remote procedure call (RPC) protocol stream is incorrect. Too many parameters were provided in this RPC request. The maximum is 2100. how do i make increase the limit or just avoid getting this error.. and put values in gridview thanks..

  Read the article

• Strategy for Storing Multiple Nullable Booleans in SQL

  - by Eric J.

  I have an object (happens to be C#) with about 20 properties that are nullable booleans. There will be perhaps a few million such objects persisted to a SQL database (currently SQL Server 2008 R2, but MySQL may need to be supported in the future). The instances themselves are relatively large because they contain about a paragraph of text as well as some other unrelated properties. For a given object instance, most of the properties will be null most of the time. When users search for instances of such objects, they will select perhaps 1-3 of the nullable boolean properties and search for instances where at least one of those 1-3 properties is non-null (OR search). My first thought is to persist the object to a single table with nullable BIT columns representing the nullable boolean properties. However, this strategy will require one index per BIT column to avoid performing a table scan when searching. Further, each index would not be particularly selective since there are only three possible values per index. Is there a better way to approach this problem?

  Read the article

• ASP.NET MVC. Hot to guess autogenerated id value ?

  - by Andrew Florko

  My web form contains list of dynamic fields that are generated like this: <% for (int i = 0; i < Model.Options.Count; i++) { %> ... <%= Html.Hidden("Options[" + i + "].Id", Model.Options[i].Id)%> <%= Html.CheckBox("Options[" + i + "].Selected", Model.Options[i].Selected)%> ... This maps perfectly on array of controller method parameters as described in Model Binding To A List article. I want to add label for checkboxes to title them, but I have to guess their ids in hmtl layout. Options[" + i + "].Selected turns into Options_0__Selected How can I avoid hardcoding Id generation in-built asp.net mvc rules? Thank you advance.

  Read the article

< Previous Page | 380 381 382 383 384 385 386 387 388 389 390 391  | Next Page >