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  • Extending EF4 SQL Generation

    - by Basiclife
    Hi, We're using EF4 in a fairly large system and occasionally run into problems due to EF4 being unable to convert certain expressions into SQL. At present, we either need to do some fancy footwork (DB/Code) or just accept the performance hit and allow the query to be executed in-memory. Needless to say neither of these is ideal and the hacks we've sometimes had to use reduce readability / maintainability. What we would ideally like is a way to extend the SQL generation capabilities of the EF4 SQL provider. Obviously there are some things like .Net method calls which will always have to be client-side but some functionality like date comparisons (eg Group by weeks in Linq to Entities ) should be do-able. I've Googled but perhaps I'm using the wrong terminology as all I get is information about the new features of EF4 SQL Generation. For such a flexible and extensible framework, I'd be surprised if this isn't possible. In my head, I'm imagining inheriting from the [SQL 2008] provider and extending it to handle additional expressions / similar in the expression tree it's given to convert to SQL. Any help/pointers appreciated. We're using VS2010 Ultimate, .Net 4 (non-client profile) and EF4. The app is in ASP.Net and is running in a 64-Bit environment in case it makes a difference.

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  • Array property in Phing

    - by Jahangir
    I have a phing build file that checks the permission of certain files using the <touch> task. <target description="list of files to check permission" name="files-to-test"> <property name="filesToCheck" value=""/> <php expression="file_get_contents('filesToCheck.txt')" returnProperty="filesToCheck"/> <foreach list="${filesToCheck}" param="file" target="permission-test"/> </target> <target description="Test the permission of files that needs to be written" name="permission-test"> <touch file="${file}"/> </target> It calls an extenal file(filesToCheck.txt) which is just a list of different file locations. This works fine. But it prevents me from reusing the same list in my PHP code when I want to access a particular file based on a certain key from the same external file(filesToCheck.txt). I looked through Phing's documentation but didn't find any array Task. Does anyone know of a work around or is creating a new task the only solution for handling an array property in Phing ?

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  • Best approach for a multi-tab ASP.NET AJAX control?

    - by NovaJoe
    Looking for some implementation advice: I have a page that has a 3-tab ajaxToolkit:TabContainer. The purpose of the page is to expose a calculator that has two basic inputs: geo-location and date. The three tabs are labeled "City and State", "Postal Code", and "GPS Coordinates". The layout of each tab container is the same for each tab, with the exception of the location section; the location section changes because each type of location has different inputs. For example, to specify city/state, there will be three fields: city, country, and state (country and state will use cascading drop-down lists). But Postal code requires only one field (which will validate via regular expression for allowed countries). See the example design mockup: So, what I WOULD LIKE to do (in order to minimize duplicate code), is to have a common control that contains the layout and structure of the calculator without specifying anything about the location section. Then, I'd like to be able to pull in each of the unique location controls based on what tab is selected. The tab structure exists at the page level, not in a control. Any advice? I was looking at templated controls (see MSDN article here), but I'm not convinced that it's the right solution. If I HAVE to create three separate controls with similar layouts and common elements, then that's what I have to do. But REALLY, I'd prefer a more elegant, inheritance-based solution. Any advice would be greatly appreciated. Thanks.

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  • Best approach, Dynamic OpenXML in T-SQL

    - by Martin Ongtangco
    hello, i'm storing XML values to an entry in my database. Originally, i extract the xml datatype to my business logic then fill the XML data into a DataSet. I want to improve this process by loading the XML right into the T-SQL. Instead of getting the xml as string then converting it on the BL. My issue is this: each xml entry is dynamic, meaning it can be any column created by the user. I tried using this approach, but it's giving me an error: CREATE PROCEDURE spXMLtoDataSet @id uniqueidentifier, @columns varchar(max) AS BEGIN -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. SET NOCOUNT ON; DECLARE @name varchar(300); DECLARE @i int; DECLARE @xmlData xml; (SELECT @xmlData = data, @name = name FROM XmlTABLES WHERE (tableID = ISNULL(@id, tableID))); EXEC sp_xml_preparedocument @i OUTPUT, @xmlData DECLARE @tag varchar(1000); SET @tag = '/NewDataSet/' + @name; DECLARE @statement varchar(max) SET @statement = 'SELECT * FROM OpenXML(@i, @tag, 2) WITH (' + @columns + ')'; EXEC (@statement); EXEC sp_xml_removedocument @i END where i pass a dynamically written @columns. For example: spXMLtoDataSet 'bda32dd7-0439-4f97-bc96-50cdacbb1518', 'ID int, TypeOfAccident int, Major bit, Number_of_Persons int, Notes varchar(max)' but it kept on throwing me this exception: Msg 137, Level 15, State 2, Line 1 Must declare the scalar variable "@i". Msg 319, Level 15, State 1, Line 1 Incorrect syntax near the keyword 'with'. If this statement is a common table expression or an xmlnamespaces clause, the previous statement must be terminated with a semicolon.

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  • Regex to ensure group match doesn't end with a specific character

    - by AJ
    I'm having trouble coming up with a regular expression to match a particular case. I have a list of tv shows in about 4 formats: Name.Of.Show.S01E01 Name.Of.Show.0101 Name.Of.Show.01x01 Name.Of.Show.101 What I want to match is the show name. My main problem is that my regex matches the name of the show with a preceding '.'. My regex is the following: "^([0-9a-zA-Z\.]+)(S[0-9]{2}E[0-9]{2}|[0-9]{4}|[0-9]{2}x[0-9]{2}|[0-9]{3})" Some Examples: >>> import re >>> SHOW_INFO = re.compile("^([0-9a-zA-Z\.]+)(S[0-9]{2}E[0-9]{2}|[0-9]{4}|[0-9]{2}x[0-9]{2}|[0-9]{3})") >>> match = SHOW_INFO.match("Name.Of.Show.S01E01") >>> match.groups() ('Name.Of.Show.', 'S01E01') >>> match = SHOW_INFO.match("Name.Of.Show.0101") >>> match.groups() ('Name.Of.Show.0', '101') >>> match = SHOW_INFO.match("Name.Of.Show.01x01") >>> match.groups() ('Name.Of.Show.', '01x01') >>> match = SHOW_INFO.match("Name.Of.Show.101") >>> match.groups() ('Name.Of.Show.', '101') So the question is how do I avoid the first group ending with a period? I realize I could simply do: var.strip(".") However, that doesn't handle the case of "Name.Of.Show.0101". Is there a way I could improve the regex to handle that case better? Thanks in advance.

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  • How do you localize/internationalize an MVC Controller when using a SQL based localization provider?

    - by EBarr
    Hopefully this isn't too silly of a question. In MVC there appears to be plenty of localization support in the views. Once I get to the controller, however, it becomes murky. Using meta:resourcekey="blah" is out, same with <%$ Resources:PageTitle.Text%. ASP.NET MVC - Localization Helpers -- suggested extensions for the Html helper classes like Resource(this Controller controller, string expression, params object[] args). Similarly, Localize your MVC with ease suggested a slightly different extension like Localize(this System.Web.UI.UserControl control, string resourceKey, params object[] args) None of these approaches works while in a controller. I put together the below function and I'm using the controllers full class name as my VirtualPath. But I'm new to MVC and assume there's a better way. public static string Localize (System.Type theType, string resourceKey, params object[] args) { string resource = (HttpContext.GetLocalResourceObject(theType.FullName, resourceKey) ?? string.Empty).ToString(); return mergeTokens(resource, args); } Thoughts? Comments?

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  • How to render a DateTime in a specific format in ASP.NET MVC 3?

    - by Slauma
    If I have in my model class a property of type DateTime how can I render it in a specific format - for example in the format which ToLongDateString() returns? I have tried this... @Html.DisplayFor(modelItem => item.MyDateTime.ToLongDateString()) ...which throws an exception because the expression must point to a property or field. And this... @{var val = item.MyDateTime.ToLongDateString(); Html.DisplayFor(modelItem => val); } ...which doesn't throw an exception, but the rendered output is empty (although val contains the expected value, as I could see in the debugger). Thanks for tips in advance! Edit ToLongDateString is only an example. What I actually want to use instead of ToLongDateString is a custom extension method of DateTime and DateTime?: public static string FormatDateTimeHideMidNight(this DateTime dateTime) { if (dateTime.TimeOfDay == TimeSpan.Zero) return dateTime.ToString("d"); else return dateTime.ToString("g"); } public static string FormatDateTimeHideMidNight(this DateTime? dateTime) { if (dateTime.HasValue) return dateTime.Value.FormatDateTimeHideMidNight(); else return ""; } So, I think I cannot use the DisplayFormat attribute and DataFormatString parameter on the ViewModel properties.

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  • BindingFlags.DeclaredOnly alternative to avoid ambiguous properties of derived classes

    - by JoeBilly
    I'am looking for a solution to access 'flatten' (lowest) properties values of a class and its derived via reflection by property names. ie access either Property1 or Property2 from the ClassB or ClassC type : public class ClassA { public virtual object Property1 { get; set; } public object Property2 { get; set; } } public class ClassB : ClassA { public override object Property1 { get; set; } } public class ClassC : ClassB { } Using simple reflection works until you have virtual properties that are overrired (ie Property1 from ClassB). Then you get a AmbiguousMatchException because the searcher don't know if you want the property of the main class or the derived. Using BindingFlags.DeclaredOnly avoid the AmbiguousMatchException but unoverrided virtual properties or derived classes properties are ommited (ie Property2 from ClassB). Is there an alternative to this poor workaround : // Get the main class property with the specified propertyName PropertyInfo propertyInfo = _type.GetProperty(propertyName, BindingFlags.DeclaredOnly | BindingFlags.Public | BindingFlags.Instance | BindingFlags.Static); // If not found, get the property wherever it is if (propertyInfo == null) propertyInfo = _type.GetProperty(propertyName); Furthermore, this workaround not resolve the reflection of 2nd level properties : getting Property1 from ClassC and AmbiguousMatchException is back. My thoughts : I have no choice except loop... Erk... ?? I'am open to Emit, Lambda (is the Expression.Call can handle this?) even DLR solution. Thanks !

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  • adding multiple <asp:Hyperlink>s into a repeater

    - by Colin Pickard
    I have a repeater control, and I want to put an unknown number of <asp:Hyperlink>s into the template, for example if you start with this: <asp:Repeater runat="server" ID="PetsRepeater"> <ItemTemplate> <%#DataBinder.Eval(Container.DataItem, "Owner")%> <%#this.ListPets(Container.DataItem)%> </ItemTemplate> </asp:Repeater> and in code behind: public partial class test1 : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { PetOwner p = new PetOwner() { Owner = "Jimmy", PetNames = new List<String>() { "Nemo", "Dory" } }; List<PetOwner> PetOwners = new List<PetOwner>() { p }; PetsRepeater.DataSource = PetOwners; PetsRepeater.DataBind(); } } protected String ListPets(Object PetOwner) { StringBuilder sb = new StringBuilder(); foreach (String Name in ((PetOwner)PetOwner).PetNames) { if (sb.Length > 0) sb.Append(", "); sb.Append(Name); } return sb.ToString(); } } class PetOwner { public String Owner; public List<String> PetNames; } Now suppose instead of having the string "Nemo, Dory" in my repeater, I want something like this: <asp:HyperLink runat=server Text="Nemo" NavigateUrl="Pet.aspx?Name=Nemo" />, <asp:HyperLink runat=server Text="Dory" NavigateUrl="Pet.aspx?Name=Dory" /> How can I do that? I tried putting a foreach inline in the aspx page, but I get the error Invalid expression term 'foreach'.

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  • Bash and regex problem : check for tokens entered into a Coke vending machine

    - by Michael Mao
    Hi all: Here is a "challenge question" I've got from Linux system programming lecture. Any of the following strings will give you a Coke if you kick: L = { aaaa, aab, aba, baa, bb, aaaa"a", aaaa"b", aab"a", … ab"b"a, ba"b"a, ab"bbbbbb"a, ... } The letters shown in wrapped double quotes indicate coins that would have fallen through (but those strings are still part of the language in this example). Exercise (a bit hard) show this is the language of a regular expression And this is what I've got so far : #!/usr/bin/bash echo "A bottle of Coke costs you 40 cents" echo -e "Please enter tokens (a = 10 cents, b = 20 cents) in a sequence like 'abba' :\c" read tokens #if [ $tokens = aaaa ]||[ $tokens = aab ]||[ $tokens = bb ] #then # echo "Good! now a coke is yours!" #else echo "Thanks for your money, byebye!" if [[ $token =~ 'aaaa|aab|bb' ]] then echo "Good! now a coke is yours!" else echo "Thanks for your money, byebye!" fi Sadly it doesn't work... always outputs "Thanks for your money, byebye!" I believe something is wrong with syntax... We didn't provided with any good reference book and the only instruction from the professor was to consult "anything you find useful online" and "research the problem yourself" :( I know how could I do it in any programming language such as Java, but get it done with bash script + regex seems not "a bit hard" but in fact "too hard" for anyone with little knowledge on something advanced as "lookahead"(is this the terminology ?) I don't know if there is a way to express the following concept in the language of regex: Valid entry would consist of exactly one of the three components : aaaa, aab and bb, regardless of order, followed by an arbitrary sequence of a or b's So this is what is should be like : (a{4}Ua{2}bUb{2})(aUb)* where the content in first braces is order irrelevant. Thanks a lot in advance for any hints and/or tips :)

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  • Munging non-printable characters to dots using string.translate()

    - by Jim Dennis
    So I've done this before and it's a surprising ugly bit of code for such a seemingly simple task. The goal is to translate any non-printable character into a . (dot). For my purposes "printable" does exclude the last few characters from string.printable (new-lines, tabs, and so on). This is for printing things like the old MS-DOS debug "hex dump" format ... or anything similar to that (where additional whitespace will mangle the intended dump layout). I know I can use string.translate() and, to use that, I need a translation table. So I use string.maketrans() for that. Here's the best I could come up with: filter = string.maketrans( string.translate(string.maketrans('',''), string.maketrans('',''),string.printable[:-5]), '.'*len(string.translate(string.maketrans('',''), string.maketrans('',''),string.printable[:-5]))) ... which is an unreadable mess (though it does work). From there you can call use something like: for each_line in sometext: print string.translate(each_line, filter) ... and be happy. (So long as you don't look under the hood). Now it is more readable if I break that horrid expression into separate statements: ascii = string.maketrans('','') # The whole ASCII character set nonprintable = string.translate(ascii, ascii, string.printable[:-5]) # Optional delchars argument filter = string.maketrans(nonprintable, '.' * len(nonprintable)) And it's tempting to do that just for legibility. However, I keep thinking there has to be a more elegant way to express this!

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  • Best Practice - Removing item from generic collection in C#

    - by Matt Davis
    I'm using C# in Visual Studio 2008 with .NET 3.5. I have a generic dictionary that maps types of events to a generic list of subscribers. A subscriber can be subscribed to more than one event. private static Dictionary<EventType, List<ISubscriber>> _subscriptions; To remove a subscriber from the subscription list, I can use either of these two options. Option 1: ISubscriber subscriber; // defined elsewhere foreach (EventType event in _subscriptions.Keys) { if (_subscriptions[event].Contains(subscriber)) { _subscriptions[event].Remove(subscriber); } } Option 2: ISubscriber subscriber; // defined elsewhere foreach (EventType event in _subscriptions.Keys) { _subscriptions[event].Remove(subscriber); } I have two questions. First, notice that Option 1 checks for existence before removing the item, while Option 2 uses a brute force removal since Remove() does not throw an exception. Of these two, which is the preferred, "best-practice" way to do this? Second, is there another, "cleaner," more elegant way to do this, perhaps with a lambda expression or using a LINQ extension? I'm still getting acclimated to these two features. Thanks. EDIT Just to clarify, I realize that the choice between Options 1 and 2 is a choice of speed (Option 2) versus maintainability (Option 1). In this particular case, I'm not necessarily trying to optimize the code, although that is certainly a worthy consideration. What I'm trying to understand is if there is a generally well-established practice for doing this. If not, which option would you use in your own code?

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  • Use auto_ptr in VC6 dll cause crash

    - by Yan Cheng CHEOK
    // dll #include <memory> __declspec(dllexport) std::auto_ptr<int> get(); __declspec(dllexport) std::auto_ptr<int> get() { return std::auto_ptr<int>(new int()); } // exe #include <iostream> #include <memory> __declspec(dllimport) std::auto_ptr<int> get(); int main() { { std::auto_ptr<int> x = get(); } std::cout << "done\n"; getchar(); } The following code run perfectly OK under VC9. However, under VC6, I will experience an immediate crash with the following message. Debug Assertion Failed! Program: C:\Projects\use_dynamic_link\Debug\use_dynamic_link.exe File: dbgheap.c Line: 1044 Expression: _CrtIsValidHeapPointer(pUserData) Is it exporting auto_ptr under VC6 is not allowed? It is a known problem that exporting STL collection classes through DLL. http://stackoverflow.com/questions/2451714/access-violation-when-accessing-an-stl-object-through-a-pointer-or-reference-in-a However, I Google around and do not see anything mention for std::auto_ptr. Any workaround?

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  • How to instantiate spring bean without being referenced from aop:aspect

    - by XDeveloper
    Using Spring and Java; I have a pointcut which works OK. Now I want to remove the pointcut and AOP from the spring and just trigger the event with an event from inside the java code but I want "myAdvice" bean still called via Spring and its properties set. I want to get ridoff all advice things even in java code, no more advice or any trace of AOP, I already have a nice event system working. I just want to instantiate my bean via Spring. When I remove the second code block (one starting with "aop:config") then I noticed the bean "myAdvice" is not called and instantiated anymore. How can i stil call it set its properties without referencing it from the "aop:aspect" ? in my application context ; <bean id="myAdvice" class="com.myclass"> <property name="name1" ref="ref1" /> <property name="name2" ref="ref2" /> </bean> <aop:config proxy-target-class="true"> <aop:aspect id="myAspect" ref="myAdvice"> <aop:pointcut id="myPointcut" expression="execution(* com.myexcmethod" /> <aop:around pointcut-ref="myPointcut" method="invoke" /> </aop:aspect> </aop:config>

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  • Calling PHP functions within HEREDOC strings

    - by Doug Kavendek
    In PHP, the HEREDOC string declarations are really useful for outputting a block of html. You can have it parse in variables just by prefixing them with $, but for more complicated syntax (like $var[2][3]), you have to put your expression inside {} braces. In PHP 5, it is possible to actually make function calls within {} braces inside a HEREDOC string, but you have to go through a bit of work. The function name itself has to be stored in a variable, and you have to call it like it is a dynamically-named function. For example: $fn = 'testfunction'; function testfunction() { return 'ok'; } $string = <<< heredoc plain text and now a function: {$fn()} heredoc; As you can see, this is a bit more messy than just: $string = <<< heredoc plain text and now a function: {testfunction()} heredoc; There are other ways besides the first code example, such as breaking out of the HEREDOC to call the function, or reversing the issue and doing something like: ?> <!-- directly outputting html and only breaking into php for the function --> plain text and now a function: <?PHP print testfunction(); ?> The latter has the disadvantage that the output is directly put into the output stream (unless I'm using output buffering), which might not be what I want. So, the essence of my question is: is there a more elegant way to approach this? Edit based on responses: It certainly does seem like some kind of template engine would make my life much easier, but it would require me basically invert my usual PHP style. Not that that's a bad thing, but it explains my inertia.. I'm up for figuring out ways to make life easier though, so I'm looking into templates now.

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  • Need variable width negative lookbehind replacement

    - by Technoh
    I have looked at many questions here (and many more websites) and some provided hints but none gave me a definitive answer. I know regular expressions but I am far from being a guru. This particular question deals with regex in PHP. I need to locate words in a text that are not surrounded by a hyperlink of a given class. For example, I might have This <a href="blabblah" class="no_check">elephant</a> is green and this elephant is blue while this <a href="blahblah">elephant</a> is red. I would need to match against the second and third elephants but not the first (identified by test class "no_check"). Note that there could more attributes than just href and class within hyperlinks. I came up with ((?<!<a .*class="no_check".*>)\belephant\b) which works beautifully in regex test software but not in PHP. Any help is greatly appreciated. If you cannot provide a regular expression but can find some sort of PHP code logic that would circumvent the need for it, I would be equally grateful.

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  • Combine regular expressions for splitting camelCase string into words

    - by stou
    I managed to implement a function that converts camel case to words, by using the solution suggested by @ridgerunner in this question: Split camelCase word into words with php preg_match (Regular Expression) However, I want to also handle embedded abreviations like this: 'hasABREVIATIONEmbedded' translates to 'Has ABREVIATION Embedded' I came up with this solution: <?php function camelCaseToWords($camelCaseStr) { // Convert: "TestASAPTestMore" to "TestASAP TestMore" $abreviationsPattern = '/' . // Match position between UPPERCASE "words" '(?<=[A-Z])' . // Position is after group of uppercase, '(?=[A-Z][a-z])' . // and before group of lowercase letters, except the last upper case letter in the group. '/x'; $arr = preg_split($abreviationsPattern, $camelCaseStr); $str = implode(' ', $arr); // Convert "TestASAP TestMore" to "Test ASAP Test More" $camelCasePattern = '/' . // Match position between camelCase "words". '(?<=[a-z])' . // Position is after a lowercase, '(?=[A-Z])' . // and before an uppercase letter. '/x'; $arr = preg_split($camelCasePattern, $str); $str = implode(' ', $arr); $str = ucfirst(trim($str)); return $str; } $inputs = array( 'oneTwoThreeFour', 'StartsWithCap', 'hasConsecutiveCAPS', 'ALLCAPS', 'ALL_CAPS_AND_UNDERSCORES', 'hasABREVIATIONEmbedded', ); echo "INPUT"; foreach($inputs as $val) { echo "'" . $val . "' translates to '" . camelCaseToWords($val). "'\n"; } The output is: INPUT'oneTwoThreeFour' translates to 'One Two Three Four' 'StartsWithCap' translates to 'Starts With Cap' 'hasConsecutiveCAPS' translates to 'Has Consecutive CAPS' 'ALLCAPS' translates to 'ALLCAPS' 'ALL_CAPS_AND_UNDERSCORES' translates to 'ALL_CAPS_AND_UNDERSCORES' 'hasABREVIATIONEmbedded' translates to 'Has ABREVIATION Embedded' It works as intended. My question is: Can I combine the 2 regular expressions $abreviationsPattern and camelCasePattern so i can avoid running the preg_split() function twice?

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  • Binding a date string parameter in an MS Access PDO query

    - by harryg
    I've made a PDO database class which I use to run queries on an MS Access database. When querying using a date condition, as is common in SQL, dates are passed as a string. Access usually expects the date to be surrounded in hashes however. E.g. SELECT transactions.amount FROM transactions WHERE transactions.date = #2013-05-25#; If I where to run this query using PDO I might do the following. //instatiate pdo connection etc... resulting in a $db object $stmt = $db->prepare('SELECT transactions.amount FROM transactions WHERE transactions.date = #:mydate#;'); //prepare the query $stmt->bindValue('mydate', '2013-05-25', PDO::PARAM_STR); //bind the date as a string $stmt->execute(); //run it $result = $stmt->fetch(); //get the results As far as my understanding goes the statement that results from the above would look like this as binding a string results in it being surrounded by quotes: SELECT transactions.amount FROM transactions WHERE transactions.date = #'2013-05-25'#; This causes an error and prevents the statement from running. What's the best way to bind a date string in PDO without causing this error? I'm currently resorting to sprintf-ing the string which I'm sure is bad practise. Edit: if I pass the hash-surrounded date then I still get the error as below: Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[22018]: Invalid character value for cast specification: -3030 [Microsoft][ODBC Microsoft Access Driver] Data type mismatch in criteria expression. (SQLExecute[-3030] at ext\pdo_odbc\odbc_stmt.c:254)' in C:\xampp\htdocs\ips\php\classes.php:49 Stack trace: #0 C:\xampp\htdocs\ips\php\classes.php(49): PDOStatement-execute() #1 C:\xampp\htdocs\ips\php\classes.php(52): database-execute() #2 C:\xampp\htdocs\ips\try2.php(12): database-resultset() #3 {main} thrown in C:\xampp\htdocs\ips\php\classes.php on line 49

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  • Getting the first result from a LINQ query - why does ElementAt<T>(0) fails when First<T>() succeeds

    - by Mr Roys
    I have a method AddStudent() which looks for a student with the same name and returns an existing student from the database if there is a student with the same name, otherwise it creates a new student and adds it to the database. I'm curious why se = students.First<StudentEntity>(); succeeds when se = students.ElementAt<StudentEntity>(0); fails when I try to get the first result from the LINQ query. Aren't the two methods the same? The full code for the method is shown below. public Student AddStudent(string name) { using (SchoolEntities db = new SchoolEntities()) { // find student with same name via LINQ var students = from s in db.StudentEntitySet where s.name == name select s; StudentEntity se = default(StudentEntity); // if student with the same name is already present, return // that student if (students.Count<StudentEntity>() > 0) { // if i use ElementAt, if fails with a "LINQ to Entities does not // recognize the method 'StudentEntity ElementAt[StudentEntity] // (System.Linq.IQueryable`1[StudentEntity], Int32)' method, // and this method cannot be translated into a store expression.", // but not when I use First. Why? // se = students.ElementAt<StudentEntity>(0); se = students.First<StudentEntity>(); } else { // passing 0 for first parameter (id) since it's represented by // a BigInt IDENTITY field in the database so any value // doesn't matter. se = StudentEntity.CreateStudentEntity(0, name); db.AddToStudentEntitySet(se); db.SaveChanges(); } // create a Student object from the Entity object return new Student(se); } } Thanks!

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  • rpy2: Converting a data.frame to a numpy array

    - by Mike Dewar
    I have a data.frame in R. It contains a lot of data : gene expression levels from many (125) arrays. I'd like the data in Python, due mostly to my incompetence in R and the fact that this was supposed to be a 30 minute job. I would like the following code to work. To understand this code, know that the variable path contains the full path to my data set which, when loaded, gives me a variable called immgen. Know that immgen is an object (a Bioconductor ExpressionSet object) and that exprs(immgen) returns a data frame with 125 columns (experiments) and tens of thousands of rows (named genes). robjects.r("load('%s')"%path) # loads immgen e = robjects.r['data.frame']("exprs(immgen)") expression_data = np.array(e) This code runs, but expression_data is simply array([[1]]). I'm pretty sure that e doesn't represent the data frame generated by exprs() due to things like: In [40]: e._get_ncol() Out[40]: 1 In [41]: e._get_nrow() Out[41]: 1 But then again who knows? Even if e did represent my data.frame, that it doesn't convert straight to an array would be fair enough - a data frame has more in it than an array (rownames and colnames) and so maybe life shouldn't be this easy. However I still can't work out how to perform the conversion. The documentation is a bit too terse for me, though my limited understanding of the headings in the docs implies that this should be possible. Anyone any thoughts?

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  • Preserving SCRIPT tags (and more) in CKEditor

    - by Jonathan Sampson
    Update: I'm thinking the solution to this problem is in CKEDITOR.config.protectedSource(), but my regular-expression experience is proving to be too juvenile to handle this issue. How would I go about exempting all tags that contain the 'preserved' class from being touched by CKEditor? Is it possible to create a block of code within the CKEditor that will not be touched by the editor itself, and will be maintained in its intended-state until explicitly changed by the user? I've been attempting to input javascript variables (bound in script tags) and a flash movie following, but CKEditor continues to rewrite my pasted code/markup, and in doing so breaking my code. I'm working with the following setup: <script type="text/javascript"> var editor = CKEDITOR.replace("content", { height : "500px", width : "680px", resize_maxWidth : "680px", resize_minWidth : "680px", toolbar : [ ['Source','-','Save','Preview'], ['Cut','Copy','Paste','PasteText','PasteFromWord','-','Print', 'SpellChecker', 'Scayt'], ['Undo','Redo','-','Find','Replace','-','SelectAll','RemoveFormat'], ['Bold','Italic','Underline','Strike','-','Subscript','Superscript'], ['NumberedList','BulletedList','-','Outdent','Indent','Blockquote'], ['JustifyLeft','JustifyCenter','JustifyRight','JustifyBlock'], ['Link','Unlink','Anchor'], ['Image','Table','HorizontalRule','SpecialChar'] ] }); CKFinder.SetupCKEditor( editor, "<?php print url::base(); ?>assets/ckfinder" ); </script> UPDATE: I suppose the most ideal solution would be to preserve the contents of any tag that contains class="preserve" enabling much more than the limited exclusives.

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  • Django aggregate query generating SQL error

    - by meepmeep
    I'm using Django 1.1.1 on a SQL Server 2005 db using the latest sqlserver_ado library. models.py includes: class Project(models.Model): name = models.CharField(max_length=50) class Thing(models.Model): project = models.ForeignKey(Project) reference = models.CharField(max_length=50) class ThingMonth(models.Model): thing = models.ForeignKey(Thing) timestamp = models.DateTimeField() ThingMonthValue = models.FloatField() class Meta: db_table = u'ThingMonthSummary' In a view, I have retrieved a queryset called 'things' which contains 25 Things: things = Thing.objects.select_related().filter(project=1).order_by('reference') I then want to do an aggregate query to get the average ThingMonthValue for the first 20 of those Things for a certain period, and the same value for the last 5. For the first 20 I do: averageThingMonthValue = ThingMonth.objects.filter(turbine__in=things[:20],timestamp__range="2009-01-01 00:00","2010-03-00:00")).aggregate(Avg('ThingMonthValue'))['ThingMonthValue__avg'] This works fine, and returns the desired value. For the last 5 I do: averageThingMonthValue = ThingMonth.objects.filter(turbine__in=things[20:],timestamp__range="2009-01-01 00:00","2010-03-00:00")).aggregate(Avg('ThingMonthValue'))['ThingMonthValue__avg'] But for this I get an SQL error: 'Only one expression can be specified in the select list when the subquery is not introduced with EXISTS.' The SQL query being used by django reads: SELECT AVG([ThingMonthSummary].[ThingMonthValue]) AS [ThingMonthValue__avg] FROM [ThingMonthSummary] WHERE ([ThingMonthSummary].[thing_id] IN (SELECT _row_num, [id] FROM ( SELECT ROW_NUMBER() OVER ( ORDER BY [AAAA].[id] ASC) as _row_num, [AAAA].[id] FROM ( SELECT U0.[id] FROM [Thing] U0 WHERE U0.[project_id] = 1 ) AS [AAAA]) as QQQ where 20 < _row_num) AND [ThingMonthSummary].[timestamp] BETWEEN '01/01/09 00:00:00' and '03/01/10 00:00:00') Any idea why it works for one slice of the Things and not the second? I've checked and the two slices do contain the desired Things correctly.

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  • How does Select statement works in a Dynamic Linq Query?

    - by Richard77
    Hello, 1) I've a Product table with 4 columns: ProductID, Name, Category, and Price. Here's the regular linq to query this table. public ActionResult Index() { private ProductDataContext db = new ProductDataContext(); var products = from p in db.Products where p.Category == "Soccer" select new ProductInfo { Name = p.Name, Price = p.Price} return View(products); } Where ProductInfo is just a class that contains 2 properties (Name and Price). The Index page Inherits ViewPage - IEnumerable - ProductInfo. Everything works fine. 2) To dynamicaly execute the above query, I do this: Public ActionResult Index() { var products = db.Products .Where("Category = \"Soccer\"") .Select(/* WHAT SOULD I WRITE HERE TO SELECT NAME & PRICE?*/) return View(products); } I'm using both 'System.Lind.Dynamic' namespace and the DynamicLibrary.cs (downloaded from ScottGu blog). Here are my questions: What expression do I use to select only Name and Price? (Most importantly) How do I retrieve the data in my view? (i.e. What type the ViewPage inherits? ProductInfo?)

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  • python histogram one-liner

    - by mykhal
    there are many ways, how to code histogram in Python. by histogram, i mean function, counting objects in an interable, resulting in the count table (i.e. dict). e.g.: >>> L = 'abracadabra' >>> histogram(L) {'a': 5, 'b': 2, 'c': 1, 'd': 1, 'r': 2} it can be written like this: def histogram(L): d = {} for x in L: if x in d: d[x] += 1 else: d[x] = 1 return d ..however, there are much less ways, how do this in a single expression. if we had "dict comprehensions" in python, we would write: >>> { x: L.count(x) for x in set(L) } but we don't have them, so we have to write: >>> dict([(x, L.count(x)) for x in set(L)]) however, this approach may yet be readable, but is not efficient - L is walked-through multiple times, so this won't work for single-life generators.. the function should iterate well also through gen(), where: def gen(): for x in L: yield x we can go with reduce (R.I.P.): >>> reduce(lambda d,x: dict(d, x=d.get(x,0)+1), L, {}) # wrong! oops, does not work, the key name is 'x', not x :( i ended with: >>> reduce(lambda d,x: dict(d.items() + [(x, d.get(x, 0)+1)]), L, {}) (in py3k, we would have to write list(d.items()) instead of d.items(), but it's hypothethical, since there is no reduce there) please beat me with a better one-liner, more readable! ;)

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  • WPF DataBinding to standard CLR properties in code-behind

    - by nukefusion
    Hi everyone, Just learning WPF databinding and have a gap in my understanding. I've seen a few similar questions on StackOverflow, but I'm still struggling in determining what I have done wrong. I have a simple Person class with a Firstname and Surname property (standard CLR properties). I also have a standard CLR property on my Window class that exposes an instance of Person. I've then got some XAML, with two methods of binding. The first works, the second doesn't. Can anybody help me to understand why the second method fails? There's no binding error message in the Output log. <Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WpfApplication1" Title="Window1" Height="300" Width="300" DataContext="{Binding RelativeSource={RelativeSource Self}, Path=MyPerson}"> <StackPanel> <Label>My Person</Label> <WrapPanel> <Label>First Name:</Label> <Label Content="{Binding RelativeSource={RelativeSource AncestorType=Window, Mode=FindAncestor}, Path=MyPerson.FirstName}"></Label> </WrapPanel> <WrapPanel> <Label>Last Name:</Label> <Label Content="{Binding MyPerson.Surname}"></Label> </WrapPanel> </StackPanel> Edit: Ok, thanks so far. I've changed the second expression to: <Label Content="{Binding Surname}"></Label> I still can't get it to work though!

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