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• MYSQL, Subquery Reference in Union

  - by christian

  Is there any way to reference a subquery in a union? I am trying to do something like the following, and would like to avoid a temporary table, but the subquery will be drawn from a much larger dataset so it makes sense to only do it once.. SELECT * FROM (SELECT * FROM ads WHERE state='FL' AND city='Maitland' AND page='home' ORDER BY RAND()) AS sq WHERE spot = 'full-banner' LIMIT 1 UNION SELECT * FROM sq WHERE spot = 'leaderboard' LIMIT 1 UNION SELECT * FROM sq WHERE spot = 'rectangle1' LIMIT 1 UNION SELECT * FROM sq WHERE spot = 'rectangle2' LIMIT 1 .... etc,, It's a shame that DISTINCT can't be specified for a single column of a result set.

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• R- delete rows in multiple columns by unique number

  - by Vincent Moriarty

  Given data like this C1<-c(3,-999.000,4,4,5) C2<-c(3,7,3,4,5) C3<-c(5,4,3,6,-999.000) DF<-data.frame(ID=c("A","B","C","D","E"),C1=C1,C2=C2,C3=C3) How do I go about removing the -999.000 data in all of the columns I know this works per column DF2<-DF[!(DF$C1==-999.000 | DF$C2==-999.000 | DF$C3==-999.000),] But I'd like to avoid referencing each column. I am thinking there is an easy way to reference all of the columns in a particular data frame aka: DF3<-DF[!(DF[,]==-999.000),] or DF3<-DF[!(DF[,(2:4)]==-999.000),] but obviously these do not work And out of curiosity, bonus points if you can me why I need that last comma before the ending square bracket as in: ==-999.000),]

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• GUID.TryParse() ?

  - by Jack Marchetti

  Obviously there is no public GUID.TryParse() in .NET CLR 2.0. So, I was looking into regular expressions [aka googling around to find one] and each time I found one there was a heated argument in the comments section about RegEx A doesn't work, use RegEx B. Then someone would write Regex C yadda yadda So anyway, What I decided to do was this, but I feel bad about it. public static bool IsGuid (string possibleGuid) { try { Guid gid = new Guid(possibleGuid); return true; } catch (Exception ex) { return false; } } Obviously I don't really like this since it's been drilled into me since day one to avoid throwing exceptions if you can defensibly code around it. Does anyonek now why there is no public Guid.TryParse() in the .NET Framework? Does anyone have a real Regular Expression that will work for all GUIDs?

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• [C#] How to create a constructor of a class that return a collection of instances of that class?

  - by codemonkie

  My program has the following class definition: public sealed class Subscriber { private subscription; public Subscriber(int id) { using (DataContext dc = new DataContext()) { this.subscription = dc._GetSubscription(id).SingleOrDefault(); } } } ,where _GetSubscription() is a sproc which returns a value of type ISingleResult<_GetSubscriptionResult> Say, I have a list of type List<int> full of 1000 ids and I want to create a collection of subscribers of type List<Subscriber>. How can I do that without calling the constructor in a loop for 1000 times? Since I am trying to avoid switching the DataContext on/off so frequently that may stress the database. TIA.

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• Import data from an SSRS report via SSIS package

  - by Chris

  First, I ask that you not ask 'why.' In the famous words of Tennyson "Ours is not to reason why. Ours is but to do and die." It's one of those, "This is what you have, deal with it." situations. The source data comes from SSRS report. The goal is to load the data into a database via SSIS. The hopeful goal is to avoid human intervention in having to download the SSRS report into Excel or CSV. There will be complex SSIS processing from there on out. Any suggestions are humbly appreciated.

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• Options for header in raw byte file.

  - by Tim

  I have a large raw data file (up to 1GB) which contains raw samples from a USB data logger. I need to store extra information relating to the file (sample rate, description, trigger point, last seek position etc) and was looking into adding this as a some sort of header. The header file should ideally be human readable and flexible so I've so far ruled out some sort of binary serialization into a header. I also want to avoid two separate files as they could end up separated when copied or backed up. I remembered somebody telling me that newer *.*x Microsoft Office documents are actually a number of files in a zip. Is there a simple way to achieve this? Could I still keep the quick seek times to the raw file?

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• WebKit gets blank when clicking on the menu toolbar

  - by Miguel Ángel Ortuño

  Hi y'all. I've embebed a WebKit view into a modal dialog using Carbon and appereantly everything works fine. However there's a little problem. When I click on the menu toolbar the view gets completely blank getting visible only when I interact with it. Seems like the control stops reciving the 'paint window' event when I call MenuSelect function. All the events are managed by the parent window because of the nature of the application (videogame). Does anybody know what this behaviour is due to and how can I avoid it? Thanks for all.

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• Use HTML markup into web.config file

  - by stighy

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

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• Python: Pickling highly-recursive objects without using `setrecursionlimit`

  - by cool-RR

  I've been getting RuntimeError: maximum recursion depth exceeded when trying to pickle a highly-recursive tree object. Much like this asker here. He solved his problem by setting the recursion limit higher with sys.setrecursionlimit. But I don't want to do that: I think that's more of a workaround than a solution. Because I want to be able to pickle my trees even if they have 10,000 nodes in them. (It currently fails at around 200.) (Also, every platform's true recursion limit is different, and I would really like to avoid opening this can of worms.) Is there any way to solve this at the fundamental level? If only the pickle module would pickle using a loop instead of recursion, I wouldn't have had this problem. Maybe someone has an idea how I can cause something like this to happen, without rewriting the pickle module? Any other idea how I can solve this problem will be appreciated.

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• Persisting sensitve data in asp.net, odd implementation

  - by rawsonstreet

  For reasons not in scope of this question I have implemented a .net project in an iframe which runs from a classic asp page. The classic asp site persisted a few sensitive values by hitting the db on each page. I have passed there variables as xml to the aspx page, now I need to make these values available on any page of this .net site. I've looked into the cache object but we are on a web farm so I am not sure it would work. Is there a way I can can instantiate an object in a base page class and have other pages inherit from the base page to access these values? What is the best way to persist these values? A few more points to consider the site runs in https mode and I cannot use session variables, and I would like to avoid cookies if possible..

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• Copy and pasting code into the Python interpreter

  - by wpeters

  There is a snippet of code that I would like to copy and paste into my Python interpreter. Unfortunately due to Python's sensitivity to whitespace it is not straightforward to copy and paste it a way that makes sense. (I think the whitespace gets mangled) Is there a better way? Maybe I can load the snippet from a file. This is just an small example but if there is a lot of code I would like to avoid typing everything from the definition of the function or copy and pasting line by line. class bcolors: HEADER = '\033[95m' OKBLUE = '\033[94m' OKGREEN = '\033[92m' WARNING = '\033[93m' FAIL = '\033[91m' ENDC = '\033[0m' def disable(self): self.HEADER = '' # I think stuff gets mangled because of the extra level of indentation self.OKBLUE = '' self.OKGREEN = '' self.WARNING = '' self.FAIL = '' self.ENDC = ''

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• What are the likely main reasons my website is very slow on IE?

  - by Bhupi

  Hi, I need to know what can be the main reasons (apart from the basics like grouping CSS selectors, reducing image size, using image sprite etc.) which makes a website slow on Internet Explorer, because my website works fine on the others like FF, chrome etc. Is it the huge use of Javascript framework (ie. jQuery, extjs, prototype)? Is it because of the use of plugins based on JS framework? Should I use core javascript and remove the use of any js framework? Should I try to avoid using jQuery(document).ready()? in case of jQuery framework? Above some of the questions which I know and please answer the questions which I couldn't ask because of lesser knowledge about these. I need to make my website perform well on IE (6,7,8) also please suggest. Thanks

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• Download and replace Android resource files

  - by Casebash

  My application will have some customisation for each company that uses it. Up until now, I have been loading images and strings from resource files. The idea is that the default resources will be distributed with the application and company specific resources will be loaded from our server after they click on a link from an email to launch the initialisation intent. Does anyone know how to replace resource files? I would really like to keep using resource files to avoid rewriting a lot of code/XML. I would distribute the application from our own server, rather than through the app store, so that we could have one version per company, but unfortunately this will give quite nasty security warnings that would concern our customers.

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• What's the easiest way to implement background downloading in Wicket?

  - by David Moles

  I've got a simple Wicket form that lets users select some data and then download a ZIP file (generated on the fly) containing what they asked for. Currently the form button's onSubmit() method looks something like this: public void onSubmit() { IResourceStream stream = /* assemble the data they asked for ... */ ; ResourceStreamRequestTarget target = new ResourceStreamRequestTarget(stream); target.setFileName("download.zip"); RequestCycle.get().setRequestTarget(target); } This works, but of course the request stops there and it's impossible to display any other feedback to the user. What I'd like to have is something like the typical "Your requested download [NAME] should begin automatically. If not, click this link." Ideally, still displaying the same page, so the user can immediately select some different data and download that as well. I imagine it's possible to do this using Wicket's Ajax classes, but I've managed to avoid having to use them so far, and it's not immediately obvious to me how. What's my quickest way out, here?

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• Android / Java rare and seemingly impossible exception causing force close

  - by Guzba

  Hello all, I have an interesting problem being reported to me from an android application I have published. I have a two-dimensional array that I am iterating through using two for loops like so: for (int i = 0; i < arr.length; ++i) { for (int j = 0; j < arr[i].length; ++j) { if (arr[i][j] != 0) // does stuff } } The problem is, somehow arr[i][j] != 0 is throwing an ArrayIndexOutOfBoundsException. But very rarely. I have thousands of people use the app on a daily basis and get maybe twenty force close reports. Is this something I can't avoid, maybe a problem with the phones memory, etc. or is there something I can do that I haven't thought of yet? Thanks.

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

  - by Pangea

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

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

  - by loursonwinny

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

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• J2EE/EJB + service locator: is it safe to cache EJB Home lookup result ?

  - by Guillaume

  In a J2EE application, we are using EJB2 in weblogic. To avoid losing time building the initial context and looking up EJB Home interface, I'm considering the Service Locator Pattern. But after a few search on the web I found that event if this pattern is often recommended for the InitialContext caching, there are some negative opinion about the EJB Home caching. Questions: Is it safe to cache EJB Home lookup result ? What will happen if one my cluster node is no more working ? What will happen if I install a new version of the EJB without refreshing the service locator's cache ?

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• What is faster: multiple `send`s or using buffering?

  - by dauerbaustelle

  I'm playing around with sockets in C/Python and I wonder what is the most efficient way to send headers from a Python dictionary to the client socket. My ideas: use a send call for every header. Pros: No memory allocation needed. Cons: many send calls -- probably error prone; error management should be rather complicated use a buffer. Pros: one send call, error checking a lot easier. Cons: Need a buffer :-) malloc/realloc should be rather slow and using a (too) big buffer to avoid realloc calls wastes memory. Any tips for me? Thanks :-)

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• .htaccess stupid issue

  - by justnoone

  I have a server where I can only configure httpd using .htaccess, a cannot access global configuration. I want to rewrite almost every non-existing path to index.php, so I did something like: RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule ^(.*)$ index.php?path=$1 [L,QSA] And that is ok. But another thing I want to do is to prevent access to path where I keep PHP files (I cannot store them somewhere else) which is for example /php. I would like that anything starting with /php rewrites to index.php?path=php... so I did something like: RewriteCond %{REQUEST_URI} ^/php.* RewriteRule ^(.*)$ /index.php?path=$1 [L,QSA] And that also would work ok if I had access to global configuration. In case of per-directory configuration, when I access /php it rewrites it to index.php?path=php and than puts directory name before that: /php/index.php?path=php. I read documentation and I realize that it uses internal redirects when per-directory confoguration is used. How can I avoid this behavior?

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• c++ polymorphism and other function question

  - by aharont

  i have got this code: class father{ public: virtual void f() { cout<<1;} }; class son:public father{ public: void f() {cout<<2;} }; void test (father x){x.f();} int main(){ son s; test(s); } the question says: the output is '1', what is the rule about polymorphism that the programmer forgot and how can i fix it so the output would be '2'? there is another rule that the programmer forgot when he wrote the father class, and he need to add an empty function to avoid problems from other sons of the father class. what is the rule and what is the missing function? another question write the g function so the next code would run with no crashes int x=11; g(x)=22;

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• Safari on the iPhone & iPad gives colour feedback on touch, I want to stop this.

  - by Owen

  Clicking on an element which has a Javascript handler makes the element go have a 'grey overlay'. This is normally fine but I'm using event delegation to handle the touchdown events of many child elements. Because of the delegation the 'grey overlay' is appearing over the parent element and looks bad and confusing. I could attach event handlers to the individual elements to avoid the problem but this would be computationally very wasteful. I'd rather have some webkit css property that I can override to turn it off. I already have visual feedback in my app so the 'grey overlay' is not needed. Any ideas?

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• text between lines in css

  - by Tom91136

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

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• C# cross class enum visibility - Possible?

  - by 537mfb

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

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• Linq to SQL inheritance and Table per Class - approach needed for multiple roles

  - by Ash Machine

  I am using L2S and an inheritance model for mapping Persons against certain roles. Guy Burstein's excellent blog post explains how to accomplish this: http://blogs.microsoft.co.il/blogs/bursteg/archive/2007/10/01/linq-to-sql-inheritance.aspx However, I have a specific case where a Person has multiple roles. For example 'Jane Doe' is a Contact and a Programmer. In this model, she would need two rows in the People table, one as Contact (PersonType = 1) and one as Programmer (PersonType = 3). If she changes her last name, and that update happens in her role as Contact, I would need to change all instances of 'Jane Doe' to reflect the name change everywhere. What sort of best approach (improved data structure) could be used to change last name within all roles? Finally, I am hoping to avoid overriding each general form update events to include all instances, but that may be the only way. Any suggestions or approaches appreciated.

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