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  • Error while setting UserAcces permission for WebForms?

    - by ksg
    I've created a class named BaseClass.cs and I've written a function in its constructor. Here's how it looks public class BasePage:Page { public BasePage() { setUserPermission(); } private void setUserPermission() { String strPathAndQuery = HttpContext.Current.Request.Url.PathAndQuery; string strulr = strPathAndQuery.Replace("/SGERP/", "../"); Session["Url"] = strulr; GEN_FORMS clsForm = new GEN_FORMS(); clsForm.Form_Logical_Name = Session["Url"].ToString(); clsForm.User_ID = Convert.ToInt32(Session["User_ID"]); DataSet dsPermission = clsForm.RETREIVE_BUTTON_PERMISSIONS(); if (dsPermission.Tables.Count > 0) { if (dsPermission.Tables[1].Rows.Count > 0) { Can_Add = Convert.ToBoolean(dsPermission.Tables[1].Rows[0]["Can_Add"].ToString()); Can_Delete = Convert.ToBoolean(dsPermission.Tables[1].Rows[0]["Can_Delete"].ToString()); Can_Edit = Convert.ToBoolean(dsPermission.Tables[1].Rows[0]["Can_Edit"].ToString()); Can_Print = Convert.ToBoolean(dsPermission.Tables[1].Rows[0]["Can_Print"].ToString()); Can_View = Convert.ToBoolean(dsPermission.Tables[1].Rows[0]["Can_Print"].ToString()); } } } } I've inherited this class on my webform so that when the page loads, the setUserPermission function is executed. My webpage looks like this public partial class Setting_CompanyDetails : BasePage My problem is that I cannot access Session["Url"] in my BasePage. I'm getting the following error Session state can only be used when enableSessionState is set to true, either in a configuration file or in the Page directive. Please also make sure that System.Web.SessionStateModule or a custom session state module is included in the <configuration>\<system.web>\<httpModules> section in the application configuration. How can I solve this issue? Is this the right way to set UserPermission access?

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  • How do I set a focus property on a TextInput that is built using AddChild?

    - by Huuuze
    I have the following MXML: <mx:State name="myState"> <mx:AddChild relativeTo="{myhbox}" position="after"> <mx:Box verticalAlign="middle" horizontalAlign="center" width="100%" height="100%"> <mx:Form id="myForm" width="479" verticalScrollPolicy="off" horizontalScrollPolicy="off"> <mx:FormItem label="My Label:" fontWeight="bold" id="myLabel" direction="vertical"> <mx:TextInput id="myTextInput" width="282" /> <mx:HBox> <mx:Button label="Go" click="go();" id="goButton" /> </mx:HBox> </mx:FormItem> </mx:Form> </mx:Box> </mx:AddChild> </mx:State> How do I set focus on the TextInput field using <mx:SetProperty/>? I've tried the following, but it only results in the field being highlighted -- the cursor does not appear in the TextInput: <mx:SetProperty target="{stage}" name="focus" value="{myTextInput}"/> Long story short, I want the cursor to appear in the field. UPDATE: I figured it out. See comments for solution.

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  • Why am I unable to prevent the animation queue from stacking without breaking my code?

    - by user1888886
    I am attempting to use jquery and CSS to animate the buttons of a navigation sidebar I am using to signify which button is selected when the mouse is hovered over each. Currently, my code for the CSS appears as such: #navbutton {position:relative; width:178px; height:35px; border:1px #FFF solid; z-index:+3; font-family:'Capriola', sans-serif; font-size:18px; text-align:center;} #navbutton.button {color:#77D; background-color: #F0B0D0;} #navbutton.button_hover {color:#66C; background-color: #FCF; padding:10px;} And my jquery: <script type="text/javascript"> $(document).ready(function(){ $("#sidebar div").mouseenter(buttonHover) function buttonHover(){ $(this).stop().switchClass('button','button_hover',500); } $("#sidebar div").mouseleave(button) function button(){ $(this).stop().switchClass('button_hover','button',500); } }); </script> Before I added the .stop() to each part of the animation, the animation queue would stack up for each time the mouse was moved over each button and then removed. Now that the .stop() has been applied, however, if the mouse is moved away from a button during its animation, the button will freeze and remain in its mid-animation state, unable to be fixed by being hovered over until the page is reloaded, rather than reverting to its original mouseleave state. From everything I've read, this should not be the case. Might anyone be able to tell why my animation queue becomes broken once the .stop() is applied?

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  • Empty Datagrid problem in VB6

    - by Hybrid SyntaX
    Hello Recently, i encountered a problem; when I bind a recordset to datagrid ,and run the application the datagrid is not populated even though recordset has data I use the following code Option Explicit Dim conn As New ADODB.Connection Dim cmd As New ADODB.Command Dim recordset As New ADODB.recordset Private Sub InitializeConnection() Dim str As String str = _ "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=" + App.Path + "\phonebook.mdb;" & _ "Persist Security Info=False" conn.CursorLocation = adUseClient conn.ConnectionString = str conn.Open (conn.ConnectionString) End Sub Private Sub AbandonConnection() If conn.State <> 0 Then conn.Close End If End Sub Private Sub Persons_Read() Dim qry_all As String ' qry_all = "select * from person,web,phone Where web.personid = person.id And phone.personid = person.id" qry_all = "SELECT * FROM person" Call InitializeConnection cmd.CommandText = qry_all cmd.CommandType = adCmdText Set cmd.ActiveConnection = conn If conn.State = 1 Then Set recordset = cmd.Execute() End If Call BindDatagrid Call AbandonConnection End Sub Private Function Person_Add() End Function Private Function Person_Delete() End Function Private Function Person_Update() End Function Private Sub BindDatagrid() Set dg_Persons.DataSource = recordset dg_Persons.Refresh End Sub Private Sub cmd_Add_Click() Person_Add End Sub Private Sub cmd_Delete_Click() Person_Delete End Sub Private Sub cmd_Update_Click() Person_Update End Sub Private Sub Form_Load() Call Persons_Read End Sub Private Sub mnu_About_Click() frm_About.Show End Sub Thanks in advance

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  • Multisite Enabling a Table

    - by Joe Fitzgibbons
    I am creating a table (table A) that will have a number of columns(of course) and there will be another table (table B) that holds metadata associated to rows in table A. I am working with a multi site implementation that has one database for the whole shabang. Rows in table A could belong to any number of sites but must belong to at least one. The problem I have is I am not sure what the best practice is for defining what site each row in table A belongs to. I want performance and scalability. There is no finite number of sites going forward. Rows in table A could belong to any number of sites in the future. Right now there are only 3. My initial thoughts are to have a primary site ID in Table A and then metadata in table B will have rows defining additional sites as needed. Another thought is to have a column in Table A for each site and it is a boolean as to wether it belongs to that site. Lastly I have thought about having another table to map rows in Table A to each site. What is the best way to associate rows in a table with any number of sites with performance and scalability in mind?

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  • [PHP] MySql Proccesslist filled with "Sleep" Entries leading to "To many Connections" ?

    - by edorian
    Hi, i'd like to ask your help on a longstanding issue with php/mysql connections. Every time i execute a "SHOW PROCESSLIST" command it shows me about 400 idle (Status: Sleep) connections to the database Server emerging from our 5 Webservers. That never was much of a problem (and i didn't find a quick solution) until recently traffic numbers increased and since then MySql reports the "to many connections" Problems repeatedly, even so 350+ of those connections are in "sleep" state. Also a server can't get a mysql connection even if there are sleeping connection to that same server. All those connections vanish when a apache server is restated. The PHP Code used to create the Database connections uses the normal "mysql" Module, the "mysqli" Module, PEAR::DB and Zend Framework Db Adapter. (Different projects). NONE of the projects uses persistent connections. Raising the connection-limit is possible but doesn't seem like a good solution since it's 450 now and there are only 20-100 "real" connections at a time anyways. My question: Why are there so many connections in sleep state and how can i prevent that. Thank you for your time, if theres anything unclear or missing please let me know

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  • Should convert String to Int in java @ 1.5 or use other method?

    - by NiksBestJPro
    I'm writing a program in which I want to terminate program by pressing any key(whether character or numbers), so I did a conversion from string to int using Integer.parseInt(variable) method and compare choices if it is not desired choice it should terminate the program but it show an error Exception in thread "main" java.lang.NumberFormatException: for input string: "d". program code is as follows:- public class mainClass { public static void main(String[]ar) { double res=0; Scanner in = new Scanner(System.in); Tdata td1 = new Tdata(); //another class object System.out.println("*Temperature Conversion*"); System.out.println("------------------------------"); System.out.println("Press 1- C2F"); System.out.println("Press 2- F2C"); System.out.println("<- Press aNY kEY TO Exit -"); String choice = in.nextLine(); //==================================================================== int ch = Integer.parseInt(choice); System.out.println("String has converted: " +ch); //verifying if converted into int if(ch == 1 || ch == 2) { if(ch == 1) { td1.getVal(37.4); res = td1.C2F(); System.out.println("Resulted Temperature: "+res); } else if(ch == 2) { td1.getVal(104.2); res = td1.F2C(); System.out.println("Resulted Temperature: "+res); } else { System.out.println("mind your input plz"); } } else { System.out.println("<- You select to exit ->"); System.exit(0); } //========================================================================================= }//end of main }//end of public class Now I think that I should convert undesired input to its previous state ie. String state.. is it right way or should Try another predefined method available in api. -Thanks! Niks

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  • alternative in .Net to building Tables/TR/TD manually?

    - by egrunin
    I've got a pile of code here that looks like this: if (stateTax > 0) { tr = new TableRow(); tbl.Rows.Add(tr); td = new TableCell(); td.CssClass = "stdLabel"; td.Text = "NY State Tax"; tr.Cells.Add(td); td = new TableCell(); td.Text = string.Format("{0:C}", stateTax); td.CssClass = "justRight"; tr.Cells.Add(td); } This is a horrible hash of data and layout, but creating a special class or control every time something like this comes up seems almost as bad. What I usually do is write a helper function, which is concise but ugly: if (stateTax > 0) MakeRow(tbl, "NY State Tax", "stdLabel", string.Format("{0:C}", stateTax), "justRight"); And now I'm thinking: haven't I done this 100 times before? Isn't there a more modern way? Just to be explicit: it's a whole list of miscellaneous labels and values. They don't come from any particular data source, and the rules for when rows should be suppressed vary. This example has only two columns, but I have other places with more.

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  • How to check Isavailablity in ajax?

    - by udaya
    Hi This is what i have in my view page <td width=""><input type="text" name="txtUserName" id="txtUserName" /></td> <td><input type="button" name="CheckUsername" id="CheckUsername" value="Check Availablity" onclick="Check_User_Name();"/></td> Onclick of the button the Check_User_Name function in my ajax.js loads This is the Check_User_Name function function Check_User_Name(source) { var UserName = document.getElementById('txtUserName').value; if(window.ActiveXObject) User_Name = new ActiveXObject("Microsoft.XMLHTTP"); else if(window.XMLHttpRequest) User_Name = new XMLHttpRequest(); var URL = newURL+"ssit/system/application/views/ssitAjax.php"; URL = URL +"?CheckUsername="+UserName; User_Name.onreadystatechange = User_Name_Fun; User_Name.open("GET",URL,true); User_Name.send(null); } function User_Name_Fun() { document.getElementById('User_div').innerHTML=User_Name.responseText; } Then I can have the value in echo username then the $result has all the user name Hows can i checkIsavailablity of username from here if(($_GET['CheckUsername']!="") || (isset($_GET['CheckUsername']))) { echo $UserName = $_GET['CheckUsername'];//echo username $_SESSION['state'] = $State; $queryres = "SELECT dUser_name FROM tbl_login WHERE dIsDelete='0'"; $result = mysql_query($queryres,$cn) or die("Selection Query Failed !!!");

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  • Programming Practice

    - by deepti
    public DataTable UserUpdateTempSettings(int install_id, int install_map_id, string Setting_value,string LogFile) { SqlConnection oConnection = new SqlConnection(sConnectionString); DataSet oDataset = new DataSet(); DataTable oDatatable = new DataTable(); SqlDataAdapter MyDataAdapter = new SqlDataAdapter(); try { oConnection.Open(); cmd = new SqlCommand("SP_HOTDOC_PRINTTEMPLATE_PERMISSION", oConnection); cmd.Parameters.Add(new SqlParameter ("@INSTALL_ID", install_id)); cmd.Parameters.Add(new SqlParameter ("@INSTALL_MAP_ID", install_map_id)); cmd.Parameters.Add(new SqlParameter("@SETTING_VALUE", Setting_value)); if (LogFile != "") { cmd.Parameters.Add(new SqlParameter("@LOGFILE",LogFile)); } cmd.CommandType = CommandType.StoredProcedure; MyDataAdapter.SelectCommand = cmd; cmd.ExecuteNonQuery(); MyDataAdapter.Fill(oDataset); oDatatable = oDataset.Tables[0]; return oDatatable; } catch (Exception ex) { Utils.ShowError(ex.Message); return oDatatable; } finally { if ((oConnection.State != ConnectionState.Closed) || (oConnection.State != ConnectionState.Broken)) { oConnection.Close(); } oDataset = null; oDatatable = null; oConnection.Dispose(); oConnection = null; } } i have used execute non query.. normally its not used with data adapter... if iam not using its giving me error.. is it bad programming practice to use execute non query with data adapter

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  • Fatal error: Allowed memory size exhausted...

    - by Nano HE
    HI, I upload my php testing script to online vps server just now. The script used to parse a big size XML file(about 4M, 7000Lines). But my IE explorer show the online error message below. Fatal error: Allowed memory size of 16777216 bytes exhausted (tried to allocate 77 bytes) in /var/www/test/result/index.php on line 26 I am sure I already tested the php script on localhost successfully. Is there any configuration need be enable/modify on my VPS? Such as php.ini or some setting for apache server? I just verified there are about 200M memory usage are avaliable for my VPS. How can I fix this? ...... function startElementHandler ($parser,$name,$attrib){ global $usercount; global $userdata; global $state; // Line #26; //Debug //print "name is: ".$name."\n"; switch ($name) { case $name=="_ID" : { $userdata[$usercount]["first"] = $attrib["FIRST"]; $userdata[$usercount]["last"] = $attrib["LAST"]; $userdata[$usercount]["nick"] = $attrib["NICK"]; $userdata[$usercount]["title"] = $attrib["TITLE"]; break; } ...... default : {$state=$name;break;} } }

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  • Unnecessary Redundancy with Tables.

    - by Stacey
    My items are listed as follows; This is just a summary of course. But I'm using a method shown for the "Detail" table to represent a type of 'inheritence', so to speak - since "Item" and "Downloadable" are going to be identical except that each will have a few additional fields relevant only to them. My question is in this design pattern. This sort of thing appears many, many times in our projects - is there a more intelligent way to handle it? I basically need to normalize the tables as much as possible. I'm extremely new to databases and so this is all very confusing to me. There are 5 items. Awards, Items, Purchases, Tokens, and Downloads. They are all very, very similar, except each has a few pieces of data relevant only to itself. I've tried to use a declaration field (like an enumerator 'Type' field) in conjunction with nullable columns, but I was told that is a bad approach. What I have done is take everything similar and place it in a single table, and then each type has its own table that references a column in the 'base' table. The problem occurs with relationships, or junctions. Linking all of these back to a customer. Each type takes around 2 additional tables to properly junction all of the data together- and as such, my database is growing very, very large. Is there a smarter practice for this kind of behavior? Item ID | GUID Name | varchar(64) Product ID | GUID Name | varchar(64) Store | GUID [ FK ] Details | GUID [FK] Downloadable ID | GUID Name | varchar(64) Url | nvarchar(2048) Details | GUID [FK] Details ID | GUID Price | decimal Description | text Peripherals [ JUNCTION ] ID | GUID Detail | GUID [FK] Store ID | GUID Addresses | GUID Addresses ID | GUID Name | nvarchar(64) State | int [FK] ZipCode | int Address | nvarchar(64) State ID | int Name | varchar(32)

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  • Improving the efficiency of multiple concurrent Core Animation animations

    - by Alex
    I have a view in my app that is very similar to the month view in the built-in Calendar app. There's a subview that holds the individual cells (a custom UIView subclass that draws text into its layer), and when the user navigates to the next "month", I create the new cells and slide the view to show them. When the animation stops, I remove the old, hidden cells and set things up so it's ready to go for the next animation. This all works nicely. However, I'd like to animate the cells' text color, as in the Calendar app, so that the outgoing ones transition to a lighter color and the incoming ones transition to a darker color. The problems is that I can have as many as 70 cells, so doing individual animations is very slow -- between 5-10 fps on my iPhone 3GS. I'm trying to find a less computationally intense way of doing this. My reading of the Shark results is that the majority of the time is spent redrawing the text for each frame for each frame. This makes sense, since text rendering is hardly the cheapest operation. I've considered creating a second view -- one holding the "outgoing" state and one holding the "incoming" state and using a single opacity animation to gradually reveal the updated cells while both are sliding. I'm concerned that instead of having 70 cells, I'll have 140, which seems like a lot of views. So, is that too many views or would there be a better way of doing this?

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  • Query table value aliasing in Oracle SQL

    - by Strata
    I have a homework assignment in SQL for Oracle 10g where I have to apply union to two different select statements, to return two columns. I need the values of each cell under vendor_state to indicate CA and every other value in another state to return "Outside CA", to indicate they're elsewhere. I applied the union and produced the two columns and the listings for CA, but many other state IDs were listed and I couldn't find an explanation for how to change the actual values in the query itself. Eventually, I stumbled on an answer, but I can't explain why this works. The code is as follows: SELECT vendor_name, vendor_state FROM vendors WHERE vendor_state IN 'CA' UNION SELECT vendor_name, 'Outside CA' AS vendor_state FROM vendors WHERE vendor_state NOT IN 'CA' ORDER BY vendor_name This gives me the exact answer I need, but I don't know why the aliasing in the second select statement can behave this way....no explanation is given in my textbook and nothing I've read indicates that column aliasing can be done like this. But, by switching the column name and the alias value, I have replaced the value being returned rather than the column name itself...I'm not complaining about the result, but it would help if I knew how I did it.

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  • "javascript: void(0)" links sometimes break event handlers in internet explorer

    - by internet man
    A while back I ran in to a problem where after clicking an anchor with "javascript: void(0)" events just stopped firing. I read that following a link puts the page in a different state and in that different state events don't fire. Even though the link is not real, it sometimes confuses IE. Anyway, I removed the "javascript: void(0)"'s and the problem has not been seen again. Now, in a different application I am seeing the same thing... kinda. Clicking the "javascript: void(0)" sometimes has no ill effect. But then for some reason or another after clicking the bad link the page will stop working. Once this happens it will continue to happen consistently until the client machine is rebooted. After reboot, you are back to it sometimes happening. Crazy right? Reboot fixing a web page!?!?! So, my question is has anyone seen this before? Can anyone give an explanation for this issue? Any documentation on this issue? I can't seem to find anything on it again. Does this even make sense? I already know "javascript: void(0)" is bad practice... I am just looking to understand the issue. Specifically, this is IE7. Thanks for reading!

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  • Why are some classes created on the fly and others aren't in CakePHP 1.2.7?

    - by JoseMarmolejos
    I have the following model classes: class User extends AppModel { var $name= 'User'; var $belongsTo=array('SellerType' => array('className' => 'SellerType'), 'State' => array('className' => 'State'), 'Country' => array('className' => 'Country'), 'AdvertMethod' => array('className' => 'AdvertMethod'), 'UserType' => array('className' => 'UserType')); var $hasMany = array('UserQuery' => array('className' => 'UserQuery'));} And: class UserQuery extends AppModel { var $name = 'UserQuery'; var $belongsTo = array('User', 'ResidenceType', 'HomeType');} Everything works fine with the user class and all its associations, but the UserQuery class is being completely ignored by the orm (table name user_queries and the generated queries do cast it as UserQuery. Another weird thing is that if I delete the code inside the User class I get an error, but if I do the same for the UserQuery class I get no errors. So my question is why does cakephp generate a class on the fly for the UserQuery and ignores my class, and why doesn't it generate a class on the fly for the User as well ?

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  • Multiple Rectangle Generation

    - by user1610541
    In my code i wrote a method that creates a rectangle at mouseX, mouseY. but all it does is update the position of that rectangle so it follows the mouse, i want it to create a new one at the mouse every time the method runs, can someone please help? this is my method public void drawParticle(float x, float y){ g.drawRect(x, y, 4, 4); } The main class Control call the drawParticle method; import java.awt.Point; import java.awt.geom.Point2D; import org.newdawn.slick.GameContainer; import org.newdawn.slick.Graphics; import org.newdawn.slick.SlickException; import org.newdawn.slick.state.BasicGameState; import org.newdawn.slick.state.StateBasedGame; public class Control extends BasicGameState { public static final int ID = 1; public Methods m = new Methods(); public Graphics g = new Graphics(); int mouseX; int mouseY; public void init(GameContainer container, StateBasedGame game) throws SlickException{ } public void render(GameContainer container, StateBasedGame game, Graphics g) throws SlickException { m.drawParticle(mouseX, mouseY); } public void update(GameContainer container, StateBasedGame game, int delta) { } public void mousePressed(int button, int x, int y) { mouseX = x; mouseY = y; } public int getID() { return ID; } } Thanks - Shamus

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  • Why are my thread being terminated ?

    - by Sephy
    Hi, I'm trying to repeat calls to methods through 3 differents threads. But after I start my threads, during the next iteration of my loop, they are all terminated so nothing is executed... The code is as follows : public static void main(String[] args) { main = new Main(); pollingThread.start(); } static Thread pollingThread = new Thread() { @Override public void run() { while (isRunning) { main.poll(); // test the state of the threads try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } } }; }; public void poll() { if (clientThread == null) { clientThread = new Thread(new Runnable() { @Override public void run() { //create some objects } }); clientThread.start(); } else if (clientThread.isAlive()) { // do some treatment } if (gestionnaireThread == null) { gestionnaireThread = new Thread(new Runnable() { @Override public void run() { //create some objects }; }); gestionnaireThread.start(); } else if (gestionnaireThread.isAlive()) { // do some treatment } if (marchandThread == null) { marchandThread = new Thread(new Runnable() { @Override public void run() { // create some objects }; }); marchandThread.start(); } else if (marchandThread.isAlive()) { // do some treatment } } And for some reason, when I test the state of my different threads, they appear as runnable and then a the 2nd iteration, they are all terminated... What am I doing wrong? I actually have no error, but the threads are terminated and so my loop keeps looping and telling me the threads are terminated.... Thanks for any help.

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  • Ruby on Rails: temporarily update an attribute into cache without saving it?

    - by randombits
    I have a bit of code that depicts this hypothetical setup below. A class Foo which contains many Bars. Bar belongs to one and only one Foo. At some point, Foo can do a finite loop that lapses 2+ iterations. In that loop, something like the following happens: bar = Bar.find_where_in_use_is_zero bar.in_use = 1 Basically what find_where_in_use_is_zero does something like this in as far as SQL goes: SELECT * from bars WHERE in_use = 0 Now the problem I'm facing is that I cannot run the following line of code after bar.in_use =1 is invoked: bar.save The reason is clear, I'm still looping and the new Foo hasn't been created, so we don't have a foo_id to put into bars.foo_id. Even if I set to allow foo_id to be NULL, we have a problem where one of the bars can fail validation and the existing one was saved to the database. In my application, that doesn't work. The entire request is atomic, either all succeeds or fails together. What happens next, is that in my loop, I have the potential to select the same exact bar that I did on a previous iteration of the loop since the in_use flag will not be set to 1 until @foo.save is called. Is there anyway to work around this condition and temporarily set the in_use attribute to 1 for subsequent iterations of the loop so that I retrieve an available bar instance?

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  • Assigning address to array from heap

    - by Schaltfehler
    I want to save the state of my structs as a binary file and load them again. My structs look like this: typedef struct { uint8_t pointerLength; uint8_t *pointer; uint8_t NumBla; uinT16 Bla[MAX_NUM_Bla]; ... } BAR_STRUCT, *BAR; typedef struct { int numBar; BAR bars[MAX_NUM_BAR]; } FOO_STRUCT, *FOO; Saving is no problem, but restoring the state. Iam at the point where the bytestring from the file is on the heap and a pointer is pointing to the first adress of this string. And I do as follows: const void* dataPointer //points to adress in heap unsigned char* bytePointer = (unsigned char*)dataPointer; FOO foo = (FOO_STRUCT*)bytePointer; bytePointer += sizeof(FOO_STRUCT); for (int i=0; i < MAX_NUM_BAR; i++) { foo->bars[i] = (BAR_STRUCT*)bytePointer; } The last assignment doesn't work and I get an EXC_BAD_ACCESS. Because bars is an array of pointers i need to correct the adresses of each element is pointing to. Because they are not valid anymore. So I try to assign the adress of the object I saved in the bytesteam to foo-bars[i]; But I can not change foo-bars[i] at all. Accessing works but but assigning a new adress doesn't. I wonder why.

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  • MS SQL: How to get the newest date in a table with several equal keys

    - by Qohelet
    Unfortunately my knowledge related to statements like "group by" and "having" is quite limited, so hopefully you can help me: I have a view -here's an excerpt- (if we have some Europeans here - it's v021 of Winline/Mesonic): ID | Artikelbezeichnung1 | Bez2 | mesoyear _____________________________________________________________________ 1401MA70 | Marga ,Saracena grigio,1S,33,3/33,3 | Marazzi | 1344 1401MA70 | Marga ,Saracena grigio,1S,33,3/33,3 | Marazzi | 1356 1401MA70 | Marga ,Saracena grigio,1S,33,3/33,3 | Marazzi | 1356 1401MA71 | Marga ,Saracena beige,1S,33,3/33,3 | Marazzi | 1344 1401MA71 | Marga ,Saracena beige,1S,33,3/33,3 | Marazzi | 1356 1401MA71 | Marga ,Saracena beige,1S,33,3/33,3 | Marazzi | 1356 2401CR13 | Crista,Mahon rojo,1S,33,3/33,3 | Cristacer | 1332 2401CR13 | Crista,Mahon rojo,1S,33,3/33,3 | Cristacer | 1344 So the ID is not unique and I just need the one with the highest val in "mesoyear". My fist solution was: Select c015 as ID, c003 as Artikelbezeichnung1, c074 as Bez2, mesoyear from CWLDATEN_91.dbo.v021 group by c015 having mesoyear = max(mesoyear) But this doesn't work at all... Msg 8121, Level 16, State 1, Line 8 Column 'CWLDATEN_91.dbo.v021.mesoyear' is invalid in the HAVING clause because it is not contained in either an aggregate function or the GROUP BY clause. So I just removed the "having" statement and it went "better": Msg 8120, Level 16, State 1, Line 2 Column 'CWLDATEN_91.dbo.v021.c003' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause. So I tried to remove the error just by adding things to the "group by". And it worked. Select c015 as ID, c003 as Artikelbezeichnung1, c074 as Bez2, max(mesoyear) from CWLDATEN_91.dbo.v021 group by c015,c003,c074 gives me exactly what I want. But the correct Select contains about 24 columns and some calculations as well. The problem can't be solved just by adding all the columns to the "group by"...? Can someone please help me to find a proper command? Thank you!

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  • What encoding does c32rtomb convert to?

    - by R. Martinho Fernandes
    The functions c32rtomb and mbrtoc32 from <cuchar>/<uchar.h> are described in the C Unicode TR (draft) as performing conversions between UTF-321 and "multibyte characters". (...) If s is not a null pointer, the c32rtomb function determines the number of bytes needed to represent the multibyte character that corresponds to the wide character given by c32 (including any shift sequences), and stores the multibyte character representation in the array whose first element is pointed to by s. (...) What is this "multibyte character representation"? I'm actually interested in the behaviour of the following program: #include <cassert> #include <cuchar> #include <string> int main() { std::u32string u32 = U"this is a wide string"; std::string narrow = "this is a wide string"; std::string converted(1000, '\0'); char* ptr = &converted[0]; std::mbstate_t state {}; for(auto u : u32) { ptr += std::c32rtomb(ptr, u, &state); } converted.resize(ptr - &converted[0]); assert(converted == narrow); } Is the assertion in it guaranteed to hold1? 1 Working under the assumption that __STDC_UTF_32__ is defined.

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  • Objective-measures of the expressiveness of programming languages [closed]

    - by Casebash
    I am very interested in the expressiveness of different languages. Everyone who has programmed in multiple languages knows that sometimes a language allows you to express concepts which you can't express in other languages. You can have all kinds of subjective discussion about this, but naturally it would be better to have an objective measure. There do actually exist objective measures. One is Turing-Completeness, which means that a language is capable of generating any output that could be generated by following a sequential set of steps. There are also other lesser levels of expressiveness such as Finite State Automata. Now, except for domain specific languages, pretty much all modern languages are Turing complete. It is therefore natural to ask the following question: Can we can define any other formal measures of expressiveness which are greater than Turing completeness? Now of course we can't define this by considering the output that a program can generate, as Turing machines can already produce the same output that any other program can. But there are definitely different levels in what concepts can be expressed - surely no-one would argue that assembly language is as powerful as a modern object oriented language like Python. You could use your assembly to write a Python interpreter, so clearly any accurate objective measure would have to exclude this possibility. This also causes a problem with trying to define the expressiveness using the minimum number of symbols. How exactly to do so is not clear and indeed appears extremely difficult, but we can't assume that just because we don't know how to solve a problem, that nobody know how to. It is also doesn't really make sense to demand a definition of expressiveness before answering the question - after all the whole point of this question is to obtain such a definition. I think that my explanation will be clear enough for anyone with a strong theoretical background in computer science to understand what I am looking for. If you do have such a background and you disagree, please comment why, but if you don't thats probably why you don't understand the question.

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  • From Binary to Data Structures

    - by Cédric Menzi
    Table of Contents Introduction PE file format and COFF header COFF file header BaseCoffReader Byte4ByteCoffReader UnsafeCoffReader ManagedCoffReader Conclusion History This article is also available on CodeProject Introduction Sometimes, you want to parse well-formed binary data and bring it into your objects to do some dirty stuff with it. In the Windows world most data structures are stored in special binary format. Either we call a WinApi function or we want to read from special files like images, spool files, executables or may be the previously announced Outlook Personal Folders File. Most specifications for these files can be found on the MSDN Libarary: Open Specification In my example, we are going to get the COFF (Common Object File Format) file header from a PE (Portable Executable). The exact specification can be found here: PECOFF PE file format and COFF header Before we start we need to know how this file is formatted. The following figure shows an overview of the Microsoft PE executable format. Source: Microsoft Our goal is to get the PE header. As we can see, the image starts with a MS-DOS 2.0 header with is not important for us. From the documentation we can read "...After the MS DOS stub, at the file offset specified at offset 0x3c, is a 4-byte...". With this information we know our reader has to jump to location 0x3c and read the offset to the signature. The signature is always 4 bytes that ensures that the image is a PE file. The signature is: PE\0\0. To prove this we first seek to the offset 0x3c, read if the file consist the signature. So we need to declare some constants, because we do not want magic numbers.   private const int PeSignatureOffsetLocation = 0x3c; private const int PeSignatureSize = 4; private const string PeSignatureContent = "PE";   Then a method for moving the reader to the correct location to read the offset of signature. With this method we always move the underlining Stream of the BinaryReader to the start location of the PE signature.   private void SeekToPeSignature(BinaryReader br) { // seek to the offset for the PE signagure br.BaseStream.Seek(PeSignatureOffsetLocation, SeekOrigin.Begin); // read the offset int offsetToPeSig = br.ReadInt32(); // seek to the start of the PE signature br.BaseStream.Seek(offsetToPeSig, SeekOrigin.Begin); }   Now, we can check if it is a valid PE image by reading of the next 4 byte contains the content PE.   private bool IsValidPeSignature(BinaryReader br) { // read 4 bytes to get the PE signature byte[] peSigBytes = br.ReadBytes(PeSignatureSize); // convert it to a string and trim \0 at the end of the content string peContent = Encoding.Default.GetString(peSigBytes).TrimEnd('\0'); // check if PE is in the content return peContent.Equals(PeSignatureContent); }   With this basic functionality we have a good base reader class to try the different methods of parsing the COFF file header. COFF file header The COFF header has the following structure: Offset Size Field 0 2 Machine 2 2 NumberOfSections 4 4 TimeDateStamp 8 4 PointerToSymbolTable 12 4 NumberOfSymbols 16 2 SizeOfOptionalHeader 18 2 Characteristics If we translate this table to code, we get something like this:   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public MachineType Machine; public ushort NumberOfSections; public uint TimeDateStamp; public uint PointerToSymbolTable; public uint NumberOfSymbols; public ushort SizeOfOptionalHeader; public Characteristic Characteristics; } BaseCoffReader All readers do the same thing, so we go to the patterns library in our head and see that Strategy pattern or Template method pattern is sticked out in the bookshelf. I have decided to take the template method pattern in this case, because the Parse() should handle the IO for all implementations and the concrete parsing should done in its derived classes.   public CoffHeader Parse() { using (var br = new BinaryReader(File.Open(_fileName, FileMode.Open, FileAccess.Read, FileShare.Read))) { SeekToPeSignature(br); if (!IsValidPeSignature(br)) { throw new BadImageFormatException(); } return ParseInternal(br); } } protected abstract CoffHeader ParseInternal(BinaryReader br);   First we open the BinaryReader, seek to the PE signature then we check if it contains a valid PE signature and rest is done by the derived implementations. Byte4ByteCoffReader The first solution is using the BinaryReader. It is the general way to get the data. We only need to know which order, which data-type and its size. If we read byte for byte we could comment out the first line in the CoffHeader structure, because we have control about the order of the member assignment.   protected override CoffHeader ParseInternal(BinaryReader br) { CoffHeader coff = new CoffHeader(); coff.Machine = (MachineType)br.ReadInt16(); coff.NumberOfSections = (ushort)br.ReadInt16(); coff.TimeDateStamp = br.ReadUInt32(); coff.PointerToSymbolTable = br.ReadUInt32(); coff.NumberOfSymbols = br.ReadUInt32(); coff.SizeOfOptionalHeader = (ushort)br.ReadInt16(); coff.Characteristics = (Characteristic)br.ReadInt16(); return coff; }   If the structure is as short as the COFF header here and the specification will never changed, there is probably no reason to change the strategy. But if a data-type will be changed, a new member will be added or ordering of member will be changed the maintenance costs of this method are very high. UnsafeCoffReader Another way to bring the data into this structure is using a "magically" unsafe trick. As above, we know the layout and order of the data structure. Now, we need the StructLayout attribute, because we have to ensure that the .NET Runtime allocates the structure in the same order as it is specified in the source code. We also need to enable "Allow unsafe code (/unsafe)" in the project's build properties. Then we need to add the following constructor to the CoffHeader structure.   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public CoffHeader(byte[] data) { unsafe { fixed (byte* packet = &data[0]) { this = *(CoffHeader*)packet; } } } }   The "magic" trick is in the statement: this = *(CoffHeader*)packet;. What happens here? We have a fixed size of data somewhere in the memory and because a struct in C# is a value-type, the assignment operator = copies the whole data of the structure and not only the reference. To fill the structure with data, we need to pass the data as bytes into the CoffHeader structure. This can be achieved by reading the exact size of the structure from the PE file.   protected override CoffHeader ParseInternal(BinaryReader br) { return new CoffHeader(br.ReadBytes(Marshal.SizeOf(typeof(CoffHeader)))); }   This solution is the fastest way to parse the data and bring it into the structure, but it is unsafe and it could introduce some security and stability risks. ManagedCoffReader In this solution we are using the same approach of the structure assignment as above. But we need to replace the unsafe part in the constructor with the following managed part:   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public CoffHeader(byte[] data) { IntPtr coffPtr = IntPtr.Zero; try { int size = Marshal.SizeOf(typeof(CoffHeader)); coffPtr = Marshal.AllocHGlobal(size); Marshal.Copy(data, 0, coffPtr, size); this = (CoffHeader)Marshal.PtrToStructure(coffPtr, typeof(CoffHeader)); } finally { Marshal.FreeHGlobal(coffPtr); } } }     Conclusion We saw that we can parse well-formed binary data to our data structures using different approaches. The first is probably the clearest way, because we know each member and its size and ordering and we have control about the reading the data for each member. But if add member or the structure is going change by some reason, we need to change the reader. The two other solutions use the approach of the structure assignment. In the unsafe implementation we need to compile the project with the /unsafe option. We increase the performance, but we get some security risks.

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  • Using PHP OCI8 with 32-bit PHP on Windows 64-bit

    - by christopher.jones
    The world migration from 32-bit to 64-bit operating systems is gaining pace. However I've seen a couple of customers having difficulty with the PHP OCI8 extension and Oracle DB on Windows 64-bit platforms. The errors vary depending how PHP is run. They may appear in the Apache or PHP log: Unable to load dynamic library 'C:\Program Files (x86)\PHP\ext\php_oci8_11g.dll' - %1 is not a valid Win32 application. or Warning oci_connect(): OCIEnvNlsCreate() failed. There is something wrong with your system - please check that PATH includes the directory with Oracle Instant Client libraries Other than IIS permission issues a common cause seems to be trying to use PHP with libraries from an Oracle 64-bit database on the same machine. There is currently no 64-bit version of PHP on http://php.net/ so there is a library mismatch. A solution is to install Oracle Instant Client 32-bit and make sure that PHP uses these libraries, while not interferring with the 64-bit database on the same machine. Warning: The following hacky steps come untested from a Linux user: Unzip Oracle Instant Client 32-bit and move it to C:\WINDOWS\SYSWOW64\INSTANTCLIENT_11_2. You may need to do this in a console with elevated permissions. Edit your PATH environment variable and insert C:\WINDOWS\SYSTEM32\INSTANTCLIENT_11_2 in the directory list before the entry for the Oracle Home library. Windows makes it so all 32-bit applications that reference C:\WINDOWS\SYSTEM32 actually see the contents of the C:\WINDOWS\SYSWOW64 directory. Your 64-bit database won't find an Instant Client in the real, physical C:\WINDOWS\SYSTEM32 directory and will continue to use the database libraries. Some of our Windows team are concerned about this hack and prefer a more "correct" solution that (i) doesn't require changing the Windows system directory (ii) doesn't add to the "memory" burden about what was configured on the system (iii) works when there are multiple database versions installed. The solution is to write a script which will set the 64-bit (or 32-bit) Oracle libraries in the path as needed before invoking the relevant bit-ness application. This does have a weakness when the application is started as a service. As a footnote: If you don't have a local database and simply need to have 32-bit and 64-bit Instant Client accessible at the same time, try the "symbolic" link approach covered in the hack in this OTN forum thread. Reminder warning: This blog post came untested from a Linux user.

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