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• How can I "reset" styles for a given HTML element?

  - by Sambo

  I am working on an embeddable javascript which inserts HTML elements onto unknown pages. I have no control of the stylesheets of the pages I'll be inserting HTML into. The problem is that the HTML I insert will mistakenly stylized by the page, and I want to prevent that. What's the least verbose and/or resource intensive to go about ensuring the elements I insert are exactly as I'd like them to be? Is there an easy way to clear all styling for a given HTML element and children? In firebug, for instance, you can remove all styling. I feel like there must, and the very least should, be a native way to exempt certain HTML elements from stylesheet rules? Example: var myHTML = $("<div>my html in here</div>"); myHTML.resetAllStyles(); //<--- what would this function do? myHTML.appendTo("body"); I really want to avoid explicitly stating the attributes I want for each element I insert... PS: I have a lot of experience with JS and CSS, so you can assume that I'll understand pretty much anything you're going to tell me.

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• Does using functional languages help against computing values repeatedly?

  - by sharptooth

  Consider a function f(x,y): f(x,0) = x*x; f(0,y) = y*(y + 1); f(x,y) = f(x,y-1) + f(x-1,y); If one tries to implement that recursively in some language like C++ he will encounter a problem. Suppose the function is first called with x = x0 and y = y0. Then for any pair (x,y) where 0 <= x < x0 and 0 <= y < y0 the intermediate values will be computed multiple times - recursive calls will form a huge tree in which multiple leaves will in fact contain the same pairs (x,y). For pairs (x,y) where x and y are both close to 0 values will be computed numerous times. For instance, I tested a similar function implemented in C++ - for x=20 and y=20 its computation takes about 4 hours (yes, four Earth hours!). Obviously the implementation can be rewritten in such way that repeated computation doesn't occur - either iteratively or with a cache table. The question is: will functional languages perform any better and avoid repeated computations when implementing a function like above recursively?

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• stop form during submission if it validates incorrectly

  - by muqman

  I am trying to use JavaScript to validate forms but if the form doesn't validate, I don't want the form to be sent to the "action" page. The validator: <script> function formSubmit() { document.getElementById("signup_form").submit(); var x=document.forms["signup_form"]["tname"].value; if (x==null || x=="") { alert("First name must be filled out"); return false; } } </script> The form itself: <form action="some_file.php" method="post" id="signup_form" name="signup_form" onsubmit="return formSubmit()"> But all this does is if the tname field empty, it will return an alert but as soon as the user hits ok, the form then redirects to some_file.php. What have I missed here? The submit button: <a href="" onclick="return formSubmit(); return false" class="purplebutton">Signup</a> So what have I missed? How do I avoid this in the future?

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• updating a column in a table only if after the update it won't be negative and identifying all updat

  - by Azeem

  Hello all, I need some help with a SQL query. Here is what I need to do. I'm lost on a few aspects as outlined below. I've four relevant tables: Table A has the price per unit for all resources. I can look up the price using a resource id. Table B has the funds available to a given user. Table C has the resource production information for a given user (including the number of units to produce everyday). Table D has the number of units ever produced by any given user (can be identified by user id and resource id) Having said that, I need to run a batch job on a nightly basis to do the following: a. for all users, identify whether they have the funds needed to produce the number of resources specified in table C and deduct the funds if they are available from table B (calculating the cost using table A). b. start the process to produce resources and after the resource production is complete, update table D using values from table C after the resource product is complete. I figured the second part can be done by using an UPDATE with a subquery. However, I'm not sure how I should go about doing part a. I can only think of using a cursor to fetch each row, examine and update. Is there a single sql statement that will help me avoid having to process each row manually? Additionally, if any rows weren't updated, the part b. SQL should not produce resources for that user. Basically, I'm attempting to modify the sql being used for this logic that currently is in a stored procedure to something that will run a lot faster (and won't process each row separately). Please let me know any ideas and thoughts. Thanks! - Azeem

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• Trouble deciding how to add popup menu to eclipse plugin using either action ObjectContributions or command handlers

  - by user1808408

  The issue is this: Most things I read on the web says that we should avoid actions when creating popup menus because the command framework allows for more decoupling. Example: http://wiki.eclipse.org/FAQ_What_is_the_difference_between_a_command_and_an_action%3F Fair enough. But I am having a heck of a time getting the command framework to add my menu when I right click on a .java file inside the editor, and only when I click inside the editor. I can get the menu to show (using 'with' and the activeEditor variable), but it also shows when I right click on the java file inside the package explorer, which I don't want. I suspect it's because the file is already open inside the editor. I also have a menu that gets added when I right click on the java file inside the package explorer, using IComplilationUnit. That works fine. So my problem is solved using a popup menu action for when I click inside the file. I also get access to to all the ISelection stuff there. But the coupling is to high and I lose the flexability of using handlers. I'm looking for either: Tell me I'm doing it the only way possible; or Tell me how to have my popup appear only when I right click on the java file editor. Regards

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• Why are my bound parameters all identical (using Linq)?

  - by Scott Stafford

  When I run this snippet of code: string[] words = new string[] { "foo", "bar" }; var results = from row in Assets select row; foreach (string word in words) { results = results.Where(row => row.Name.Contains(word)); } I get this SQL: -- Region Parameters DECLARE @p0 VarChar(5) = '%bar%' DECLARE @p1 VarChar(5) = '%bar%' -- EndRegion SELECT ... FROM [Assets] AS [t0] WHERE ([t0].[Name] LIKE @p0) AND ([t0].[Name] LIKE @p1) Note that @p0 and @p1 are both bar, when I wanted them to be foo and bar. I guess Linq is somehow binding a reference to the variable word rather than a reference to the string currently referenced by word? What is the best way to avoid this problem? (Also, if you have any suggestions for a better title for this question, please put it in the comments.) Note that I tried this with regular Linq also, with the same results (you can paste this right into Linqpad): string[] words = new string[] { "f", "a" }; string[] dictionary = new string[] { "foo", "bar", "jack", "splat" }; var results = from row in dictionary select row; foreach (string word in words) { results = results.Where(row => row.Contains(word)); } results.Dump(); Dumps: bar jack splat

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• How do I pass references as method parameters across AppDomains?

  - by Thiado de Arruda

  I have been trying to get the following code to work(everything is defined in the same assembly) : namespace SomeApp{ public class A : MarshalByRefObject { public byte[] GetSomeData() { // } } public class B : MarshalByRefObject { private A remoteObj; public void SetA(A remoteObj) { this.remoteObj = remoteObj; } } public class C { A someA = new A(); public void Init() { AppDomain domain = AppDomain.CreateDomain("ChildDomain"); string currentAssemblyPath = Assembly.GetExecutingAssembly().Location; B remoteB = domain.domain.CreateInstanceFromAndUnwrap(currentAssemblyPath,"SomeApp.B") as B; remoteB.SetA(someA); // this throws an ArgumentException "Object type cannot be converted to target type." } } } What I'm trying to do is pass a reference of an 'A' instance created in the first AppDomain to the child domain and have the child domain execute a method on the first domain. In some point on 'B' code I'm going to call 'remoteObj.GetSomeData()'. This has to be done because the 'byte[]' from 'GetSomeData' method must be 'calculated' on the first appdomain. What should I do to avoid the exception, or what can I do to achieve the same result?

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• Why is no encoding set in reponse by tomcat? How can I deal with it?

  - by Dishayloo

  I had recently a problem with encoding of websites generated by servlet, that occured if the servlets were deployed under tomcat, but not under jetty. I did a little bit of research about it and simplified the problem to the following servlet: public class TestServlet extends HttpServlet implements Servlet { @Override public void service(HttpServletRequest request, HttpServletResponse response) throws IOException { response.setContentType("text/plain"); Writer output = response.getWriter(); output.write("öäüÖÄÜß"); output.flush(); output.close(); } } If I deploy this under Jetty and direct the browser to it, it returns the expected result. The data is returned as ISO-8859-1 and if I take a look into the headers, then Jetty returns: Content-Type: text/plain; charset=iso-8859-1 The browser detects the encoding from this header. If I deploy the same servlet in a tomcat, the browser shows up strange characters. But Tomcat also returns the data as ISO-8859-1, the difference is, that no header tells about it. So the browser has to guess the encoding, and that goes wrong. My question is, is that behaviour of tomcat correct or a bug? And if it is correct, how can I avoid this problem? Sure, I can always add response.setCharacterEncoding("UTF-8"); to the servlet, but that means I set a fixed encoding, that the browser might or might not understand. The problem is more relevant, if no browser but another service accesses the servlet. So how I should deal with the problem in the most flexible way?

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• Doing a virus check on a file from a build script

  - by the_mandrill

  I would like to be be able to invoke a virus check as the final stage of the build process (please don't question why a dev machine would get a virus, it's just a belt-and-braces approach to avoid the risk of getting sued by customers...). Also I'd like the option of having AV on a machine but switching the auto file system protection off (at least for the build directories). What I would like is a generic way of scanning a file using whatever AV system is in place. I'm assuming that there's an Windows API to do this, given that Windows detects the presence of an AV system, and browsers such as Firefox invoke a virus scan whenever a file is downloaded. So what's the API that they're using? There's the Microsoft AntiVirus API but that seems to be specific to Office documents. Does the approach involve using WMI? (and if you can detect the AV provider from there, how do you then invoke it to scan a file?) I know that I could write the script to manually call the AV scanner that I know to be installed, but as an intellectual exercise I'm more interested to know how apps like Firefox are doing this.

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• Question about array subscripting in C#

  - by Michael J

  Back in the old days of C, one could use array subscripting to address storage in very useful ways. For example, one could declare an array as such. This array represents an EEPROM image with 8 bit words. BYTE eepromImage[1024] = { ... }; And later refer to that array as if it were really multi-dimensional storage BYTE mpuImage[2][512] = eepromImage; I'm sure I have the syntax wrong, but I hope you get the idea. Anyway, this projected a two dimension image of what is really single dimensional storage. The two dimensional projection represents the EEPROM image when loaded into the memory of an MPU with 16 bit words. In C one could reference the storage multi-dimensionaly and change values and the changed values would show up in the real (single dimension) storage almost as if by magic. Is it possible to do this same thing using C#? Our current solution uses multiple arrays and event handlers to keep things synchronized. This kind of works but it is additional complexity that we would like to avoid if there is a better way.

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• "pseudo-atomic" operations in C++

  - by dan

  So I'm aware that nothing is atomic in C++. But I'm trying to figure out if there are any "pseudo-atomic" assumptions I can make. The reason is that I want to avoid using mutexes in some simple situations where I only need very weak guarantees. 1) Suppose I have globally defined volatile bool b, which initially I set true. Then I launch a thread which executes a loop while(b) doSomething(); Meanwhile, in another thread, I execute b=true. Can I assume that the first thread will continue to execute? In other words, if b starts out as true, and the first thread checks the value of b at the same time as the second thread assigns b=true, can I assume that the first thread will read the value of b as true? Or is it possible that at some intermediate point of the assignment b=true, the value of b might be read as false? 2) Now suppose that b is initially false. Then the first thread executes bool b1=b; bool b2=b; if(b1 && !b2) bad(); while the second thread executes b=true. Can I assume that bad() never gets called? 3) What about an int or other builtin types: suppose I have volatile int i, which is initially (say) 7, and then I assign i=7. Can I assume that, at any time during this operation, from any thread, the value of i will be equal to 7? 4) I have volatile int i=7, and then I execute i++ from some thread, and all other threads only read the value of i. Can I assume that i never has any value, in any thread, except for either 7 or 8? 5) I have volatile int i, from one thread I execute i=7, and from another I execute i=8. Afterwards, is i guaranteed to be either 7 or 8 (or whatever two values I have chosen to assign)?

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• global variables doesn't change value in Javascript

  - by user1856906

  My project is composed by 2 html pages: 1)index.html, wich contains the login and the registration form. 2)user_logged.html, wich contains all the features of a logged user. Now, what I want to do is a control if the user is really logged, to avoid the case where a user paste a url in the browser and can see the pages of another user. hours as now, if a user paste this url in the browser: www.user_loggato.html?user=x#profile is as if logged in as user x and this is not nice. My html pages both use js files that contains scripts. I decided to create a global variable called logged inizialized to false and change the variable to true when the login is succesfull. The problem is that the variable, remains false. here is the code: var logged=false; (write in the file a.js) while in the file b.js I have: function login() { //if succesfull logged=true; window.location.href = "user_loggato.html?user="+ JSON.parse(str).username + #profilo"; Now with some alerts I found that my variable logged is always false. Why? if I have not explained well or if there is not some information in order to respond to my question let me know.

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• Passing XML data and user from coldfusion page to .NET page

  - by Mark Rullo

  I'd appreciate some input on this situation, I can't figure out the best way to do this. I have some data that's being prepared for me in a ColdFusion app and in an IFrame within the CF app we want to display some graphs (not strictly an image, it's an entire page) being generated on the .NET side of things. I'd like to pass XML data from the CF side to .NET as well as the user. On the .NET side I'm putting the data in a session so the user can sift through it without the need to have it re-queried and re-passed from CF. What I've tried: Generating XML with CF, putting it in a hidden form field, auto-submitting (with JS) a the form to the .NET side. The issue I'm having with this approach is the encoding being done on the form post. The data has entries like <entry data="hello &amp; goodbye">. It's an issue because it's being URL encdeded, Posted, and when I get it on the .NET side I get <entry data="hello & goodbye"> which isn't properly formed XML. What I'd like to avoid: An intermediary DB approach (dropping the data in a DB on CF, picking it up with .NET) I'd like to only display what is passed to the page. I have security concerns with the data, it's very sensitive. Passing the data to a webservice, returning a GUID, forwarding the user with a URL Parameter to access the passed in data. I think that'd be risky if someone happened on a link to that data. I can't take that risk. I was thinking of passing the data with JSON, but I'm very unfamiliar with it. Thoughts? Thanks for your time folks.

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• The right approach to loading dynamic content into a UITableView in iOS

  - by OS.

  ok, I've read tons of bits and pieces on the subject of loading dynamic content (from the web) into a UITableView and the problem with calculating cell height upfront. I've tried different simple implementations but the problem persists... Assuming I need to read a JSON file from the web, parse it into 'item' objects, each with variable size image and various text labels, here is what I believe would be the right approach to avoid long hang time of the app while everything is loading: on app load read JSON file and parse into items array provide only small part of the items array to the tableview (about 10 items) - since I need to load the images associated with each item to calculate cell height - I don't want the view to go through the whole items list and load all images - this hangs the app until every image is loaded display the tableview with the available cells (assuming I load a few 'spare' ones, user can even scroll to more items) in the background using Grand Central Dispatch download images for all/some of the remaining items and then reload the tableview with the new data (repeat step 4 if item list is very long) Step 2 above is necessary since I have no way to calculate the cell height without loading the images first, and since tableview first calculates height of all cells it may take a very long time to download all images for all items. Would you say this is the right approach? am I missing something?

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• SQL Server 2005: Internal Query Processor Error:

  - by Geetha

  I am trying to execute this following procedure in SQL Server 2005. I was able to execute this in my development server and when i tried to use this in the Live Server I am getting an Error "Internal Query Processor Error: The query processor could not produce a query plan. For more information, contact Customer Support Services". am using the same Database and the same format. when we searched in the web it shows some fixes to be used in sql server 2005 to avoid this error but my DBA has confirmed that all the patches are updated in our server. can anyone give me some clue on this. Query: create Procedure [dbo].[sample_Select] @ID as varchar(40) as Declare @Execstring as varchar(1000) set @Execstring = ' Declare @MID as varchar(40) Set @MID = '''+@ID+''' select * from ( select t1.field1, t1.field2 AS field2 , t1.field3 AS field3 , L.field1 AS field1 , L. field2 AS field2 from table1 AS t1 INNER JOIN MasterTable AS L ON L. field1 = t1. field2 where t1. field2 LIKE @MID ) as DataTable PIVOT ( Count(field2) FOR field3 IN (' Select @Execstring=@Execstring+ L.field2 +',' FROM MasterTable AS L inner join table1 AS t1 ON t1.field1= L.field2 Where t1.field2 LIKE @ID set @Execstring = stuff(@Execstring, len(@Execstring), 1, '') set @Execstring =@Execstring +')) as pivotTable' exec (@Execstring)

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• Cursor loops; How to perform something at start/end of loop 1 time only?

  - by James.Elsey

  I've got the following in one of my Oracle procedures, I'm using it to generate XML -- v_client_addons is set to '' to avoid null error OPEN C_CLIENT_ADDONS; LOOP FETCH C_CLIENT_ADDONS INTO CLIENT_ADDONS; EXIT WHEN C_CLIENT_ADDONS%NOTFOUND; BEGIN v_client_addons := v_client_addons || CLIENT_ADDONS.XML_DATA; END; END LOOP; CLOSE C_CLIENT_ADDONS; -- Do something later with v_client_addons The loop should go through my cursor and pick out all of the XML values to display, such as : <add-on name="some addon"/> <add-on name="another addon"/> What I would like to achieve is to have an XML start/end tag inside this loop, so I would have the following output <addons> <add-on name="some addon"/> <add-on name="another addon"/> </addons> How can I do this without having the <addons> tag after every line? If there are no addons in the cursor (cursor is empty), then I would like to skip this part enitrely

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• Color banding only on Android 4.0+

  - by threeshinyapples

  On emulators running Android 4.0 or 4.0.3, I am seeing horrible colour banding which I can't seem to get rid of. On every other Android version I have tested, gradients look smooth. I have a SurfaceView which is configured as RGBX_8888, and the banding is not present in the rendered canvas. If I manually dither the image by overlaying a noise pattern at the end of rendering I can make the gradients smooth again, though obviously at a cost to performance which I'd rather avoid. So the banding is being introduced later. I can only assume that, on 4.0+, my SurfaceView is being quantized to a lower bit-depth at some point between it being drawn and being displayed, and I can see from a screen capture that gradients are stepping 8 values at a time in each channel, suggesting a quantization to 555 (not 565). I added the following to my Activity onCreate function, but it made no difference. getWindow().setFormat(PixelFormat.RGBA_8888); getWindow().addFlags(WindowManager.LayoutParams.FLAG_DITHER); I also tried putting the above in onAttachedToWindow() instead, but there was still no change. (I believe that RGBA_8888 is the default window format anyway for 2.2 and above, so it's little surprise that explicitly setting that format has no effect on 4.0+.) Which leaves the question, if the source is 8888 and the destination is 8888, what is introducing the quantization/banding and why does it only appear on 4.0+? Very puzzling. I wonder if anyone can shed some light?

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• How to synchronize two (or n) replication processes for SQL Server databases?

  - by Yauheni Sivukha

  There are two master databases and two read-only copies updated by standard transactional replication. It is needed to map some entity from both read-only databases, lets say that A databases contains orders and B databases contains lines. The problem is that replication to one database can lag behind replication of second database, and at the moment of mapping R-databases will have inconsistent data. For example. We stored 2 orders with lines at 19:00 and 19:03. Mapping process started at 19:05, but to the moment of mapping A database replication processed all changes up to 19:03, but B database replication processed only changes up to 19:00. After mapping we will have order entity with order as of 19:03 and lines as of 19:00. The troubles are guaranteed:) In my particular case both databases have temporal model, so it is possible to fetch data for every time slice, but the problem is to identify time of latest replication. Question: How to synchronize replication processes for several databases to avoid situation described above? Or, in other words, how to compare last time of replication in each database? UPD: The only way I see to synchronize is to continuously write timestamps into service tables in each database and to check these timestamps on replicated servers. Is that acceptable solution?

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• C++ map performance - Linux (30 sec) vs Windows (30 mins) !!!

  - by sonofdelphi

  I need to process a list of files. The processing action should not be repeated for the same file. The code I am using for this is - using namespace std; vector<File*> gInputFileList; //Can contain duplicates, File has member sFilename map<string, File*> gProcessedFileList; //Using map to avoid linear search costs void processFile(File* pFile) { File* pProcessedFile = gProcessedFileList[pFile->sFilename]; if(pProcessedFile != NULL) return; //Already processed foo(pFile); //foo() is the action to do for each file gProcessedFileList[pFile->sFilename] = pFile; } void main() { size_t n= gInputFileList.size(); //Using array syntax (iterator syntax also gives identical performance) for(size_t i=0; i<n; i++){ processFile(gInputFileList[i]); } } The code works correctly, but... My problem is that when the input size is 1000, it takes 30 minutes - HALF AN HOUR - on Windows/Visual Studio 2008 Express (both Debug and Release builds). For the same input, it takes only 40 seconds to run on Linux/gcc! What could be the problem? The action foo() takes only a very short time to execute, when used separately. Should I be using something like vector::reserve for the map?

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• wpautop() - when shortcode attributes are on new lines -breaks args array

  - by Luca

  I have a custom shortcode tag with a few attributes, and I would like to be able to display its attributes on new lines - to make it more readable to content editors: [component attr1 ="value1" attr2 ="value of the second one" attr3 ="another" attr4 ="value" ... attrN ="valueN"] The reason behind this requirement is that a few attributes might be quite verbose in content. Unfortunately, wpautop() adds some nasty extra markup that breaks the args array like this (using php print_r($args)): Array ( [0] => attr1 [1] => ="value1" /> [3] => attr2 = [4] => "value [5] => of [6] => the [7] => second [8] => one" /> [10] => "" //...and more like this) I've tried with the attributes inline: [component attr1 ="value1" attr2 ="value of the second one" ="value"... attrN ="valueN"] and the output is as expected: Array ( [attr1] => value1 [attr2] => value of the second one [attr3] => //...and so on) is there any way to have the attributes intented and avoid that extra markup that breaks the $args array?

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• sending address of a variable declared on the stack?

  - by kobac

  I have a doubt concerning declaring variables, their scope, and if their address could be sent to other functions even if they are declared on the stack? class A{ AA a; void f1(){ B b; aa.f2(&b); } }; class AA{ B* mb; f2(B* b){ mb = b; //... } }; Afterwards, I use my AA::mb pointer in the code. So things I would like to know are following. When the program exits A::f1() function, b variable since declared as a local variable and placed on the stack, can't be used anymore afterwards. What happens with the validity of the AA::mb pointer? It contains the address of the local variable which could not be available anymore, so the pointer isn't valid anymore? If B class is a std::<vector>, and AA::mb is not a pointer anymore to that vector, but a vector collection itself for example. I would like to avoid copying all of it's contents in AA::f2() to a member AA::mb in line mb = b. Which solution would you recommend since I can't assign a pointer to it, because it'll be destroyed when the program exits AA::f2()

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• howto catch jQuery for multiple links but not all

  - by user247245

  I'm trying to dig into jQuery but would like some feedback on how to do things the best way, I have a list with items, which each contains a hidden div that should show upon click on it's parent, list div:ed item1 with link hidden div div:ed item2 with link hidden div .. My current solution is to trace the calling link by it's id and then reusing that ID for showing the correct hidden one: $(document).ready(function() { //jQ should only trigger on links with id="cmLinkINT" $("a").click(function() { //see if it's a comment request. var s = $(this).attr("id"); if (s.indexOf('cmLink') != -1) { //ok, it was a 'show'-link, get the id.. var j = s.substring(6); //ok, now I have the id i want to show (detailsINT) return false; } }); }); What's not clear to me is the best approach, Should I use id for requesting a or trace the id of the parent div. How to avoid that the code triggers on any link? Class? Thankful for any feedback, regards //t

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• How can I set paperclip's storage mechanism based on the current Rails environment?

  - by John Reilly

  I have a rails application that has multiple models with paperclip attachments that are all uploaded to S3. This app also has a large test suite that is run quite often. The downside with this is that a ton of files are uploaded to our S3 account on every test run, making the test suite run slowly. It also slows down development a bit, and requires you to have an internet connection in order to work on the code. Is there a reasonable way to set the paperclip storage mechanism based on the Rails environment? Ideally, our test and development environments would use the local filesystem storage, and the production environment would use S3 storage. I'd also like to extract this logic into a shared module of some kind, since we have several models that will need this behavior. I'd like to avoid a solution like this inside of every model: ### We don't want to do this in our models... if Rails.env.production? has_attached_file :image, :styles => {...}, :storage => :s3, # ...etc... else has_attached_file :image, :styles => {...}, :storage => :filesystem, # ...etc... end Any advice or suggestions would be greatly appreciated! :-)

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• Resource allocation and automatic deallocation

  - by nabulke

  In my application I got many instances of class CDbaOciNotifier. They all share a pointer to only one instance of class OCIEnv. What I like to achieve is that allocation and deallocation of the resource class OCIEnv will be handled automatically inside class CDbaOciNotifier. The desired behaviour is, with the first instance of class CDbaOciNotifier the environment will be created, after that all following notifiers use that same environment. With the destruction of the last notifier, the environment will be destroyed too (call to custom deleter). What I've got so far (using a static factory method to create notifiers): #pragma once #include <string> #include <memory> #include "boost\noncopyable.hpp" class CDbaOciNotifier : private boost::noncopyable { public: virtual ~CDbaOciNotifier(void); static std::auto_ptr<CDbaOciNotifier> createNotifier(const std::string &tnsName, const std::string &user, const std::string &password); private: CDbaOciNotifier(OCIEnv* envhp); // All notifiers share one environment static OCIEnv* m_ENVHP; // Custom deleter static void freeEnvironment(OCIEnv *env); OCIEnv* m_envhp; }; CPP: #include "DbaOciNotifier.h" using namespace std; OCIEnv* CDbaOciNotifier::m_ENVHP = 0; CDbaOciNotifier::~CDbaOciNotifier(void) { } CDbaOciNotifier::CDbaOciNotifier(OCIEnv* envhp) :m_envhp(envhp) { } void CDbaOciNotifier::freeEnvironment(OCIEnv *env) { OCIHandleFree((dvoid *) env, (ub4) OCI_HTYPE_ENV); *env = null; } auto_ptr<CDbaOciNotifier> CDbaOciNotifier::createNotifier(const string &tnsName, const string &user, const string &password) { if(!m_ENVHP) { OCIEnvCreate( (OCIEnv **) &m_ENVHP, OCI_EVENTS|OCI_OBJECT, (dvoid *)0, (dvoid * (*)(dvoid *, size_t)) 0, (dvoid * (*)(dvoid *, dvoid *, size_t))0, (void (*)(dvoid *, dvoid *)) 0, (size_t) 0, (dvoid **) 0 ); } //shared_ptr<OCIEnv> spEnvhp(m_ENVHP, freeEnvironment); ...got so far... return auto_ptr<CDbaOciNotifier>(new CDbaOciNotifier(m_ENVHP)); } I'd like to avoid counting references (notifiers) myself, and use something like shared_ptr. Do you see an easy solution to my problem?

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• How to handle ids and polymorphic associations in views if compound keys are not supported?

  - by duncan

  I have a Movie plan table: movie_plans (id, description) Each plan has items, which describe a sequence of movies and the duration in minutes: movie_plan_items (id, movie_plan_id, movie_id, start_minutes, end_minutes) A specific instance of that plan happens in: movie_schedules (id, movie_plan_id, start_at) However the schedule items can be calculated from the movie_plan_items and the schedule start time by adding the minutes create view movie_schedule_items as select CONCAT(p.id, '-', s.id) as id, s.id as movie_schedule_id, p.id as movie_plan_item_id, p.movie_id, p.movie_plan_id, (s.start_at + INTERVAL p.start_minutes MINUTE) as start_at, (s.start_at + INTERVAL p.end_minutes MINUTE) as end_at from movie_plan_items p, movie_schedules s where s.movie_plan_id=p.movie_plan_id; I have a model over this view (readonly), it works ok, except that the id is right now a string. I now want to add a polymorphic property (like comments) to various of the previous tables. Therefore for movie_schedule_items I need a unique and persistent numeric id. I have the following dilemma: I could avoid the id and have movie_schedule_items just use the movie_plan_id and movie_schedule_id as a compound key, as it should. But Rails sucks in this regard. I could create an id using String#hash or a md5, thus making it slower or collision prone (and IIRC String#hash is no longer persistent across processes in Ruby 1.9) Any ideas on how to handle this situation?

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