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  • Why my java app for android not connect to server?

    - by FredVaz
    Why my java app for android not connect to server ? I run the aplication in android emulator, and the server wich port 9999 and host 127.0.0.1 in my pc, but just not connect and i think this method isn't good for android app. It is my source code: import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; //Java imports //import android.util.Log; import java.io.*; import java.net.*; import java.util.*; import java.util.logging.Level; import java.util.logging.Logger; public class MainActivity extends Activity { //Variaveis Interface private Button ligar; private Button enviar; private EditText text1; private TextView text2; //Variaveis static Socket cSocket; static PrintWriter out; static BufferedReader in; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); //Declaração butões ligar = (Button) findViewById(R.id.ligar); enviar = (Button) findViewById(R.id.enviar); text1 = (EditText) findViewById(R.id.text1); text2 = (TextView) findViewById(R.id.text2); //Interacao ligar.setOnClickListener(new OnClickListener(){ public void onClick(View arg0){ connect(); } }); enviar.setOnClickListener(new OnClickListener(){ public void onClick(View arg0){ out.println("Hello"); text2.setText(""); } }); } //Outras Funcoes public void connect(){ //Funcao ligar cSocket = null; out = null; in = null; try { cSocket = new Socket("127.0.0.1",9999); out = new PrintWriter(cSocket.getOutputStream(), true); in = new BufferedReader(new InputStreamReader(cSocket.getInputStream())); text2.setText("Estas conectado com sucesso."); } catch (IOException ex) { //Logger.getLogger(client.class.getName()).log(Level.SEVERE, null, ex); text2.setText("Erro! Na conexão"); } } // }

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  • Keeping the keyboard from obscuring widgets in a form

    - by synic
    In an iPhone app, how do I keep the software keyboard from obscuring buttons, or UITextView fields in a View? I've got the following layout: View -\ UITextView UIButton ... but, the keyboard obscures the button at the bottom when I'm typing in the UITextView. I tried using the following: View -\ UIScrollView -\ UITextView UIButton ... but, the window does not scroll as expected, so the user has no way of clicking the button. How is this normally handled?

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  • wordpress query custom fields and category

    - by InnateDev
    I have a query that creates a table view and then another that queries the view. The results are extremely slow. Here is the code: create or replace view $view_table_name as select * from wp_2_postmeta where post_id IN ( select ID FROM wp_2_posts wposts LEFT JOIN wp_2_term_relationships ON (wposts.ID = wp_2_term_relationships.object_id) LEFT JOIN wp_2_term_taxonomy ON (wp_2_term_relationships.term_taxonomy_id = wp_2_term_taxonomy.term_taxonomy_id) WHERE wp_2_term_taxonomy.taxonomy = 'category' AND wp_2_term_taxonomy.parent = $cat || wp_2_term_taxonomy.term_id = $cat AND wposts.post_status = 'publish' AND wposts.post_type = 'post') The $values have been put it in for this example that queries the view table for the results. select distinct(ID) from $view_table_name wposts LEFT JOIN wp_2_postmeta wpostmeta ON wposts.ID = wpostmeta.post_id WHERE post_status = 'publish' AND ID NOT IN (SELECT post_id FROM wp_2_postmeta WHERE meta_key = '$var' && meta_value = '$value1') AND ID NOT IN (SELECT post_id FROM wp_2_postmeta WHERE meta_key = '$var' && meta_value = '$value2') AND ID NOT IN (SELECT post_id FROM wp_2_postmeta WHERE meta_key = '$var' && meta_value = '$value3') AND postmeta.meta_key = 'pd_form' ORDER BY CASE wpostmeta.meta_value WHEN '$value5' THEN 1 WHEN '$value6' THEN 2 WHEN '$value7' THEN 3 WHEN '$value8' THEN 4 WHEN '$value9' THEN 5 THEN '$value10' THEN 6 WHEN '$value11' THEN 7 WHEN '$value11' THEN 8 END

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  • CodeIgniter subfolders and URI routing

    - by shummel7845
    I’ve read the manual on URI routing and views and something is not clicking with me. In my views folder, I have a subfolder called products. In there is a file called product_view. In my controller, I have: function index() { $data['title'] = 'Product Overview'; $data['main_content'] = 'products/product_view'; $this->load->view('templates/main.php', $data); } The template loads a header view, a footer view and a navigation view, plus the view as a main content variable. In my URI routing, I have: $route['products/product-overview'] = 'products/product_view']; This causes a 404 error when I try to go to domain.com/products/product-overview. Do I need to do something with my .htaccess? If so, what? Here is my .htaccess: Options +FollowSymLinks Options -Indexes DirectoryIndex index.php RewriteEngine on RewriteCond $1 !^(index\.php|resources|images|css|js|robots\.txt|favicon\.ico) RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule ^(.*)$ index.php?/$1 [L,QSA] I’d appreciate some specific help, as the documentation isn’t specific on how to address this. I’ve done a little searching in the forums, and didn’t see anything, but I’m posting this while I keep looking.

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  • How do I push a new controller via UIButton, nested in a UIScrollView?

    - by jimijon
    Hello - I have my views that are part of a tabBar. Each view has a navigationController. In one of my views I have an embeded xib component. This is a scrolling view with UIButtons inside it. I want to slide in another view, inside the navigationController when a person taps the button. I can get the taps, etc. BUT, I can't figure out how to find the controlling navigationController of that page to push the new view into. Nothing seems to work that I have tried. IS this possible? Thanks

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  • Displaying SQL results using PHP

    - by mouthpiec
    Hi, I have an SQL query that returns an amount of tuples (about 50). Now I need to display the results, 15 tuples at a time, then I will have a "view more" button to view the next 15 results. Can you please help me how I can make this? The issue is that I cannot use the 'limits' because each time I run the query the results will be different, hence when pressing view more, I may get the same results of the same page. thanks

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  • Completely Removing Views from memory

    - by cannyboy
    I have a view which is set up to train 'voiceprints' of words (this voiceprint code is not mine), and another view which has a slideshow which is controlled by the voiceprint. Unfortunately, these views conflict because they are still in memory. As far as I know, viewDidUnload and dealloc are only called in low-memory situations, and dealloc should not be called directly, so how do I completely remove a view. These views are within uinavigationcontrollers by the way.

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  • How does one access subviews and handle groups of them?

    - by david
    If I want to manipulate a view I get it with [self viewWithTag:5];. Is there a better way to do this? Sometimes I need to manipulate a bunch of view (e.g. move them all out of the way. I do this by adding a UIView (e.g. UIView iHoldViews) and then adding the views, buttons, etc to this view. Then I can move the iHoldViews view and all its subviews move with it. Is there a better way to do this? (I have a feeling there is :) Maybe storing them in a NSArray or NSMutableDictionary ?

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  • My table cells don't highlight immediately when touched

    - by Steve Denenberg
    Hi, In my app, I have a table view that has about eight cells. There is a navigation bar at the top. When a user touches a cell, nothing happens for about 1/2 second. Then the touched cell highlights blue and immediately the new view slides into position. The problem is that there is no feedback to the user about which cell he touched until just before the new view slides into position. For example, when I explore the tables in the iPhone's Settings application, when you touch a cell, the cell immediately turns blue, and then there is a 1/2 second delay, and then you see the new view. How do I get my table's feedback of highlighting the cells to happen immediately? I am using tableView didSelectRowAtIndexPath:, and each cell has an accessory button. Thanks for any insight.

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  • strange situation of UITableView when I want to scroll it

    - by ivanlw
    I'm building an easy app for chatting, each time I type in a sentence, the sentences is added into an array(which used to load the table view in cellForRowAtIndexPath delegate method), then I reload the table view. At last I use the following code to scroll the table view to the bottom if ([self.chatList numberOfRowsInSection:0] != 0) { NSUInteger rowCount = [self.chatArray count]; NSIndexPath* indexPath = [NSIndexPath indexPathForRow:rowCount-1 inSection:0]; [self.chatList scrollToRowAtIndexPath:indexPath atScrollPosition:UITableViewScrollPositionTop animated:YES]; } however, the table view sometimes performs well, sometimes only scrolls to the second to the last line……

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  • JTable.removeColumn() method throws exception

    - by sanjeev
    To hide a column from only the view of JTable, i am using the removeColumn() method. But it throws the exception Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 7 >= 7 at java.util.Vector.elementAt(Vector.java:470) at javax.swing.table.DefaultTableColumnModel.getColumn(DefaultTableColumnModel.java:294) at javax.swing.plaf.basic.BasicTableHeaderUI.paint(BasicTableHeaderUI.java:648) i think, after removing column from the view, if i modified the model, then this exception pops out. is it because of there is no column in view, while the model is updating the table ? What is the best way to hide the column in view in JTable ? insteading of setting the sizes to 0.

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  • Select distinct ... inner join vs. select ... where id in (...)

    - by Tonio
    I'm trying to create a subset of a table (as a materialized view), defined as those records which have a matching record in another materialized view. For example, let's say I have a Users table with user_id and name columns, and a Log table, with entry_id, user_id, activity, and timestamp columns. First I create a materialized view of the Log table, selecting only those rows with timestamp some_date. Now I want a materliazed view of the Users referenced in my snapshot of the Log table. I can either create it as select * from Users where user_id in (select user_id from Log_mview), or I can do select distinct u.* from Users u inner join Log_mview l on u.user_id = l.user_id (need the distinct to avoid multiple hits from users with multiple log entries). The former seems cleaner and more elegant, but takes much longer. Am I missing something? Is there a better way to do this?

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  • ViewDidLoad not being called with my custom UIViewController

    - by user1060500
    I have created a custom UIViewController class that creates a ScrollView at runtime that it loads into the view. See code here in the constructor of my custom UIViewController. initControl(id, canEdit); _controllers = new NSMutableArray(0); //required to keep view controllers around _scrollView = new UIScrollView(); _scrollView.BackgroundColor = UIColor.Green; this.View = _scrollView; ViewDidAppear and ViewWillAppear are called normally. ViewDidLoad is not called which I am not sure why as the view is showing up on the screen just fine. Any ideas?

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  • amplified reflected attack on dns

    - by Mike Janson
    The term is new to me. So I have a few questions about it. I've heard it mostly happens with DNS servers? How do you protect against it? How do you know if your servers can be used as a victim? This is a configuration issue right? my named conf file include "/etc/rndc.key"; controls { inet 127.0.0.1 allow { localhost; } keys { "rndc-key"; }; }; options { /* make named use port 53 for the source of all queries, to allow * firewalls to block all ports except 53: */ // query-source port 53; /* We no longer enable this by default as the dns posion exploit has forced many providers to open up their firewalls a bit */ // Put files that named is allowed to write in the data/ directory: directory "/var/named"; // the default pid-file "/var/run/named/named.pid"; dump-file "data/cache_dump.db"; statistics-file "data/named_stats.txt"; /* memstatistics-file "data/named_mem_stats.txt"; */ allow-transfer {"none";}; }; logging { /* If you want to enable debugging, eg. using the 'rndc trace' command, * named will try to write the 'named.run' file in the $directory (/var/named"). * By default, SELinux policy does not allow named to modify the /var/named" directory, * so put the default debug log file in data/ : */ channel default_debug { file "data/named.run"; severity dynamic; }; }; view "localhost_resolver" { /* This view sets up named to be a localhost resolver ( caching only nameserver ). * If all you want is a caching-only nameserver, then you need only define this view: */ match-clients { 127.0.0.0/24; }; match-destinations { localhost; }; recursion yes; zone "." IN { type hint; file "/var/named/named.ca"; }; /* these are zones that contain definitions for all the localhost * names and addresses, as recommended in RFC1912 - these names should * ONLY be served to localhost clients: */ include "/var/named/named.rfc1912.zones"; }; view "internal" { /* This view will contain zones you want to serve only to "internal" clients that connect via your directly attached LAN interfaces - "localnets" . */ match-clients { localnets; }; match-destinations { localnets; }; recursion yes; zone "." IN { type hint; file "/var/named/named.ca"; }; // include "/var/named/named.rfc1912.zones"; // you should not serve your rfc1912 names to non-localhost clients. // These are your "authoritative" internal zones, and would probably // also be included in the "localhost_resolver" view above :

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  • Securing an ASP.NET MVC 2 Application

    - by rajbk
    This post attempts to look at some of the methods that can be used to secure an ASP.NET MVC 2 Application called Northwind Traders Human Resources.  The sample code for the project is attached at the bottom of this post. We are going to use a slightly modified Northwind database. The screen capture from SQL server management studio shows the change. I added a new column called Salary, inserted some random salaries for the employees and then turned off AllowNulls.   The reporting relationship for Northwind Employees is shown below.   The requirements for our application are as follows: Employees can see their LastName, FirstName, Title, Address and Salary Employees are allowed to edit only their Address information Employees can see the LastName, FirstName, Title, Address and Salary of their immediate reports Employees cannot see records of non immediate reports.  Employees are allowed to edit only the Salary and Title information of their immediate reports. Employees are not allowed to edit the Address of an immediate report Employees should be authenticated into the system. Employees by default get the “Employee” role. If a user has direct reports, they will also get assigned a “Manager” role. We use a very basic empId/pwd scheme of EmployeeID (1-9) and password test$1. You should never do this in an actual application. The application should protect from Cross Site Request Forgery (CSRF). For example, Michael could trick Steven, who is already logged on to the HR website, to load a page which contains a malicious request. where without Steven’s knowledge, a form on the site posts information back to the Northwind HR website using Steven’s credentials. Michael could use this technique to give himself a raise :-) UI Notes The layout of our app looks like so: When Nancy (EmpID 1) signs on, she sees the default page with her details and is allowed to edit her address. If Nancy attempts to view the record of employee Andrew who has an employeeID of 2 (Employees/Edit/2), she will get a “Not Authorized” error page. When Andrew (EmpID 2) signs on, he can edit the address field of his record and change the title and salary of employees that directly report to him. Implementation Notes All controllers inherit from a BaseController. The BaseController currently only has error handling code. When a user signs on, we check to see if they are in a Manager role. We then create a FormsAuthenticationTicket, encrypt it (including the roles that the employee belongs to) and add it to a cookie. private void SetAuthenticationCookie(int employeeID, List<string> roles) { HttpCookiesSection cookieSection = (HttpCookiesSection) ConfigurationManager.GetSection("system.web/httpCookies"); AuthenticationSection authenticationSection = (AuthenticationSection) ConfigurationManager.GetSection("system.web/authentication"); FormsAuthenticationTicket authTicket = new FormsAuthenticationTicket( 1, employeeID.ToString(), DateTime.Now, DateTime.Now.AddMinutes(authenticationSection.Forms.Timeout.TotalMinutes), false, string.Join("|", roles.ToArray())); String encryptedTicket = FormsAuthentication.Encrypt(authTicket); HttpCookie authCookie = new HttpCookie(FormsAuthentication.FormsCookieName, encryptedTicket); if (cookieSection.RequireSSL || authenticationSection.Forms.RequireSSL) { authCookie.Secure = true; } HttpContext.Current.Response.Cookies.Add(authCookie); } We read this cookie back in Global.asax and set the Context.User to be a new GenericPrincipal with the roles we assigned earlier. protected void Application_AuthenticateRequest(Object sender, EventArgs e){ if (Context.User != null) { string cookieName = FormsAuthentication.FormsCookieName; HttpCookie authCookie = Context.Request.Cookies[cookieName]; if (authCookie == null) return; FormsAuthenticationTicket authTicket = FormsAuthentication.Decrypt(authCookie.Value); string[] roles = authTicket.UserData.Split(new char[] { '|' }); FormsIdentity fi = (FormsIdentity)(Context.User.Identity); Context.User = new System.Security.Principal.GenericPrincipal(fi, roles); }} We ensure that a user has permissions to view a record by creating a custom attribute AuthorizeToViewID that inherits from ActionFilterAttribute. public class AuthorizeToViewIDAttribute : ActionFilterAttribute{ IEmployeeRepository employeeRepository = new EmployeeRepository(); public override void OnActionExecuting(ActionExecutingContext filterContext) { if (filterContext.ActionParameters.ContainsKey("id") && filterContext.ActionParameters["id"] != null) { if (employeeRepository.IsAuthorizedToView((int)filterContext.ActionParameters["id"])) { return; } } throw new UnauthorizedAccessException("The record does not exist or you do not have permission to access it"); }} We add the AuthorizeToView attribute to any Action method that requires authorization. [HttpPost][Authorize(Order = 1)]//To prevent CSRF[ValidateAntiForgeryToken(Salt = Globals.EditSalt, Order = 2)]//See AuthorizeToViewIDAttribute class[AuthorizeToViewID(Order = 3)] [ActionName("Edit")]public ActionResult Update(int id){ var employeeToEdit = employeeRepository.GetEmployee(id); if (employeeToEdit != null) { //Employees can edit only their address //A manager can edit the title and salary of their subordinate string[] whiteList = (employeeToEdit.IsSubordinate) ? new string[] { "Title", "Salary" } : new string[] { "Address" }; if (TryUpdateModel(employeeToEdit, whiteList)) { employeeRepository.Save(employeeToEdit); return RedirectToAction("Details", new { id = id }); } else { ModelState.AddModelError("", "Please correct the following errors."); } } return View(employeeToEdit);} The Authorize attribute is added to ensure that only authorized users can execute that Action. We use the TryUpdateModel with a white list to ensure that (a) an employee is able to edit only their Address and (b) that a manager is able to edit only the Title and Salary of a subordinate. This works in conjunction with the AuthorizeToViewIDAttribute. The ValidateAntiForgeryToken attribute is added (with a salt) to avoid CSRF. The Order on the attributes specify the order in which the attributes are executed. The Edit View uses the AntiForgeryToken helper to render the hidden token: ......<% using (Html.BeginForm()) {%><%=Html.AntiForgeryToken(NorthwindHR.Models.Globals.EditSalt)%><%= Html.ValidationSummary(true, "Please correct the errors and try again.") %><div class="editor-label"> <%= Html.LabelFor(model => model.LastName) %></div><div class="editor-field">...... The application uses View specific models for ease of model binding. public class EmployeeViewModel{ public int EmployeeID; [Required] [DisplayName("Last Name")] public string LastName { get; set; } [Required] [DisplayName("First Name")] public string FirstName { get; set; } [Required] [DisplayName("Title")] public string Title { get; set; } [Required] [DisplayName("Address")] public string Address { get; set; } [Required] [DisplayName("Salary")] [Range(500, double.MaxValue)] public decimal Salary { get; set; } public bool IsSubordinate { get; set; }} To help with displaying readonly/editable fields, we use a helper method. //Simple extension method to display a TextboxFor or DisplayFor based on the isEditable variablepublic static MvcHtmlString TextBoxOrLabelFor<TModel, TProperty>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TProperty>> expression, bool isEditable){ if (isEditable) { return htmlHelper.TextBoxFor(expression); } else { return htmlHelper.DisplayFor(expression); }} The helper method is used in the view like so: <%=Html.TextBoxOrLabelFor(model => model.Title, Model.IsSubordinate)%> As mentioned in this post, there is a much easier way to update properties on an object. Download Demo Project VS 2008, ASP.NET MVC 2 RTM Remember to change the connectionString to point to your Northwind DB NorthwindHR.zip Feedback and bugs are always welcome :-)

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  • Mark Messages As Read in the Outlook 2010 Reading Pane

    - by Matthew Guay
    Do you ever feel annoyed that Outlook 2010 doesn’t mark messages as Read as soon as you click and view them in the Reading Pane?  Here we show you how to make Outlook mark them as read as soon as they’re opened. Mark as Read By default, Outlook will not mark a message as read until you select another message.  This can be annoying, because if you read a message and immediately click Delete, it will show up as an unread message in our Deleted Items folder. Let’s change this to make Outlook mark messages as read as soon as we view them in the Reading Pane.  Open Outlook and click File to open Backstage View, and select Options. In Options select Mail on the left menu, and under Outlook panes click on the Reading Pane button. Check the box Mark items as read when viewed in the Reading Pane to make Outlook mark your messages as read when you view them in the Reading Pane.  By default, Outlook will only mark a message read after you’ve been reading it for 5 seconds, though you can change this.  We set it to 0 seconds so our messages would be marked as read as soon as we select them. Click OK in both dialogs, and now your messages will be marked as read as soon as you select them in the reading pane, or soon after, depending on your settings. Conclusion Outlook 2010 is a great email client, but like most programs it has its quirks.  This quick tip can help you get rid of one of Outlook’s annoying features, and make it work like you want it to. And, if you’re still using Outlook 2007, check out our article on how to Mark Messages as Read When Viewed in Outlook 2007. Similar Articles Productive Geek Tips Make Outlook 2007 Mark Items as Read When Viewed in Reading PaneMake Mail.app’s Reading Pane More Like OutlookIntegrate Twitter With Microsoft OutlookSort Your Emails by Conversation in Outlook 2010Find Emails With Attachments with Outlook 2007’s Instant Search TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Snagit 10 VMware Workstation 7 OpenDNS Guide Google TV The iPod Revolution Ultimate Boot CD can help when disaster strikes Windows Firewall with Advanced Security – How To Guides Sculptris 1.0, 3D Drawing app

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  • Translate Languages in IE 8 with Bing Translator

    - by Asian Angel
    Do you need side by side or hover language translations while browsing? Then join us as we look at the Bing Translator accelerator for Internet Explorer 8. Note: This article is geared towards those who may not have used this accelerator before or declined to “add it” when setting up IE 8. Using Bing Translator Once you have clicked on Add to Internet Explorer and confirmed the installation your new accelerator is ready to use. For our example we chose a Norwegian news article. Right-click within the webpage to access the context menu entry for translating. Depending on the originating language, you may want to go ahead and set it manually before beginning the translation. The translation will be opened in a new tab… Note: The same entry can also be accessed through the All Accelerators listing. There are four settings available for viewing your translations: side by side, top/bottom, original with hover translation, & translation with hover original. First a look at the side by side view. When maximized the window area will be divided 50/50 and as you hover your mouse or scroll in one side the same action will occur simultaneously in the other side. The top/bottom view. As above browser actions occur simultaneously in both sections. The original with hover translation view. Especially helpful if you are studying a new language and want to check your level of understanding for the original language. The translation with original hover view. Four different viewing options make it easy to find the one that best suits your needs. Conclusion If you need a convenient way to translate between languages in Internet Explorer 8, then the Bing Translator accelerator just might be what you have been looking for. Links Add the Bing Translator accelerator to Internet Explorer 8 Similar Articles Productive Geek Tips Quickly Translate Text to Another Language in Word 2007Add Google Translation Power to FirefoxTranslate Foreign Website Text to your Native LanguageAuto Translate Text in Google ChromeView Word Definitions in IE 8 with the Define with Bing Accelerator TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips HippoRemote Pro 2.2 Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server 24 Million Sites Windows Media Player Glass Icons (icons we like) How to Forecast Weather, without Gadgets Outlook Tools, one stop tweaking for any Outlook version Zoofs, find the most popular tweeted YouTube videos Video preview of new Windows Live Essentials

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  • How to get SQL Railroad Diagrams from MSDN BNF syntax notation.

    - by Phil Factor
    pre {margin-bottom:.0001pt; font-size:8.0pt; font-family:"Courier New"; margin-left: 0cm; margin-right: 0cm; margin-top: 0cm; } On SQL Server Books-On-Line, in the Transact-SQL Reference (database Engine), every SQL Statement has its syntax represented in  ‘Backus–Naur Form’ notation (BNF)  syntax. For a programmer in a hurry, this should be ideal because It is the only quick way to understand and appreciate all the permutations of the syntax. It is a great feature once you get your eye in. It isn’t the only way to get the information;  You can, of course, reverse-engineer an understanding of the syntax from the examples, but your understanding won’t be complete, and you’ll have wasted time doing it. BNF is a good start in representing the syntax:  Oracle and SQLite go one step further, and have proper railroad diagrams for their syntax, which is a far more accessible way of doing it. There are three problems with the BNF on MSDN. Firstly, it is isn’t a standard version of  BNF, but an ancient fork from EBNF, inherited from Sybase. Secondly, it is excruciatingly difficult to understand, and thirdly it has a number of syntactic and semantic errors. The page describing DML triggers, for example, currently has the absurd BNF error that makes it state that all statements in the body of the trigger must be separated by commas.  There are a few other detail problems too. Here is the offending syntax for a DML trigger, pasted from MSDN. Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger) CREATE TRIGGER [ schema_name . ]trigger_name ON { table | view } [ WITH <dml_trigger_option> [ ,...n ] ] { FOR | AFTER | INSTEAD OF } { [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] } [ NOT FOR REPLICATION ] AS { sql_statement [ ; ] [ ,...n ] | EXTERNAL NAME <method specifier [ ; ] > }   <dml_trigger_option> ::=     [ ENCRYPTION ]     [ EXECUTE AS Clause ]   <method_specifier> ::=  This should, of course, be /* Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger) */ CREATE TRIGGER [ schema_name . ]trigger_name ON { table | view } [ WITH <dml_trigger_option> [ ,...n ] ] { FOR | AFTER | INSTEAD OF } { [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] } [ NOT FOR REPLICATION ] AS { {sql_statement [ ; ]} [ ...n ] | EXTERNAL NAME <method_specifier> [ ; ] }   <dml_trigger_option> ::=     [ ENCRYPTION ]     [ EXECUTE AS CLAUSE ]   <method_specifier> ::=     assembly_name.class_name.method_name I’d love to tell Microsoft when I spot errors like this so they can correct them but I can’t. Obviously, there is a mechanism on MSDN to get errors corrected by using comments, but that doesn’t work for me (*Error occurred while saving your data.”), and when I report that the comment system doesn’t work to MSDN, I get no reply. I’ve been trying to create railroad diagrams for all the important SQL Server SQL statements, as good as you’d find for Oracle, and have so far published the CREATE TABLE and ALTER TABLE railroad diagrams based on the BNF. Although I’ve been aware of them, I’ve never realised until recently how many errors there are. Then, Colin Daley created a translator for the SQL Server dialect of  BNF which outputs standard EBNF notation used by the W3C. The example MSDN BNF for the trigger would be rendered as … /* Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger) */ create_trigger ::= 'CREATE TRIGGER' ( schema_name '.' ) ? trigger_name 'ON' ( table | view ) ( 'WITH' dml_trigger_option ( ',' dml_trigger_option ) * ) ? ( 'FOR' | 'AFTER' | 'INSTEAD OF' ) ( ( 'INSERT' ) ? ( ',' ) ? ( 'UPDATE' ) ? ( ',' ) ? ( 'DELETE' ) ? ) ( 'NOT FOR REPLICATION' ) ? 'AS' ( ( sql_statement ( ';' ) ? ) + | 'EXTERNAL NAME' method_specifier ( ';' ) ? )   dml_trigger_option ::= ( 'ENCRYPTION' ) ? ( 'EXECUTE AS CLAUSE' ) ?   method_specifier ::= assembly_name '.' class_name '.' method_name Colin’s intention was to allow anyone to paste SQL Server’s BNF notation into his website-based parser, and from this generate classic railroad diagrams via Gunther Rademacher's Railroad Diagram Generator.  Colin's application does this for you: you're not aware that you are moving to a different site.  Because Colin's 'translator' it is a parser, it will pick up syntax errors. Once you’ve fixed the syntax errors, you will get the syntax in the form of a human-readable railroad diagram and, in this form, the semantic mistakes become flamingly obvious. Gunter’s Railroad Diagram Generator is brilliant. To be able, after correcting the MSDN dialect of BNF, to generate a standard EBNF, and from thence to create railroad diagrams for SQL Server’s syntax that are as good as Oracle’s, is a great boon, and many thanks to Colin for the idea. Here is the result of the W3C EBNF from Colin’s application then being run through the Railroad diagram generator. create_trigger: dml_trigger_option: method_specifier:   Now that’s much better, you’ll agree. This is pretty easy to understand, and at this point any error is immediately obvious. This should be seriously useful, and it is to me. However  there is that snag. The BNF is generally incorrect, and you can’t expect the average visitor to mess about with it. The answer is, of course, to correct the BNF on MSDN and maybe even add railroad diagrams for the syntax. Stop giggling! I agree it won’t happen. In the meantime, we need to collaboratively store and publish these corrected syntaxes ourselves as we do them. How? GitHub?  SQL Server Central?  Simple-Talk? What should those of us who use the system  do with our corrected EBNF so that anyone can use them without hassle?

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  • SSAS DMVs: useful links

    - by Davide Mauri
    From time to time happens that I need to extract metadata informations from Analysis Services DMVS in order to quickly get an overview of the entire situation and/or drill down to detail level. As a memo I post the link I use most when need to get documentation on SSAS Objects Data DMVs: SSAS: Using DMV Queries to get Cube Metadata http://bennyaustin.wordpress.com/2011/03/01/ssas-dmv-queries-cube-metadata/ SSAS DMV (Dynamic Management View) http://dwbi1.wordpress.com/2010/01/01/ssas-dmv-dynamic-management-view/ Use Dynamic Management Views (DMVs) to Monitor Analysis Services http://msdn.microsoft.com/en-us/library/hh230820.aspx

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