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  • Rails find over multiple models

    - by kgb
    I think I'm missing something very obvious and its making my brain hurt. class User < ActiveRecord::Base has_one :profile class Profile < ActiveRecord::Base has_one :user belongs_to :team I have a partial that loops through the users and print some basic info, I'm using this partial in my team show page. I had originally written this to return users who's profiles were a member of a team. def show @team = Team.find_by_id(params[:id]) @profiles= Profile.find(:all, :conditions => ['team_id = ?', @team.id]) @users = User.find_by_id(@profiles.user_id) end But quickly realized @profiles was an array, and it looks messy as hell. Stuck as to what my find should look like to select all User who have a profile that is a member of a team. The partial that is working elsewhere for displaying users looks like this <% for user in @users%> <table> <tr> <td> <%= image_tag user.profile.picture.url %> </td> <td> <a href="/users/<%= user.id %>"><%= user.login %></a> </td> <td> <%= user.profile.first_name %> <%= user.profile.second_name %> </td> <td> <%= user.profile.status %> </td> </tr> </table> <% end %> Development log output with updated show and relationships Processing TeamsController#show (for 127.0.0.1 at 2010-03-30 22:06:31) [GET] Parameters: {"id"=>"1"} User Load (1.3ms) SELECT * FROM "users" WHERE ("users"."id" = 3) LIMIT 1 Team Load (1.0ms) SELECT * FROM "teams" WHERE ("teams"."id" = 1) Rendering template within layouts/main Rendering teams/show Completed in 75ms (View: 11, DB: 2) | 200 OK [http://localhost/teams/1]

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  • Access external xml using xslt document function return 401

    - by Ciprian Grosu
    On MOSS2007, I have a webpart that display the content of a xml feed. I use a xslt with parameters for transforamtions. There is a situation when I receive a 401 Authorisation exception. I realize that this happen when a document() function from my xslt try to open an external xml. If I try to open this xml in browser all work ok. I provided my admin credentials to the web part and to the XmlSecureResolver. Same problem. The webpart is on server1 and the xml feed and external xml required by xslt is on server2. What can be ? protected override void RenderContents(HtmlTextWriter writer) { base.RenderContents(writer); if (string.IsNullOrEmpty(this.xmlUrl) || this.xmlResponseStream == null) return; try { XslCompiledTransform transform = new XslCompiledTransform(); if (UseXslt) { XmlTextReader stylesheet = null; try { SPSite site = new SPSite(xsltlUrl); SPWeb web = site.OpenWeb(); SPFile file = web.GetFile(xsltlUrl); if (file != null) { stylesheet = new XmlTextReader(file.OpenBinaryStream()); } } catch(Exception ex) { stylesheet = new XmlTextReader(xsltlUrl); } if (stylesheet != null) { transform.Load(stylesheet, new XsltSettings(true, true), GetAResolver()); } using (XmlReader reader = new XmlTextReader(this.xmlResponseStream)) { string theParams = xsltProperties; XsltArgumentList xslAgrs = GetXsltArgumentList(xsltProperties); XmlTextWriter results = new XmlTextWriter(writer.InnerWriter); if (UseProperties) { transform.Transform(reader, xslAgrs, results, GetASecureResolver()); } else { transform.Transform(reader, results); } reader.Close(); } } else { string feedAsString = null; using (StreamReader rssReader = new StreamReader(this.xmlResponseStream)) { feedAsString = rssReader.ReadToEnd(); writer.InnerWriter.Write(SPHttpUtility.HtmlEncode(feedAsString)); } } } catch (Exception ex) { writer.Write(ex.Message); if (this.xmlResponseStream != null) { this.xmlResponseStream.Close(); this.xmlResponseStream.Dispose(); } } } private static XmlSecureResolver GetASecureResolver() { // Create a secure resolver XmlSecureResolver resolver = new XmlSecureResolver(new XmlUrlResolver(), "http://externalservername.com/thesite/"); string proxyUserName = RssFeedUtility.GetConfigFileReader().ProxyUserName; string proxyUserPwd = RssFeedUtility.GetConfigFileReader().ProxyUserPassword; string proxyUserDomain = RssFeedUtility.GetConfigFileReader().ProxyUserDomain; resolver.Credentials = new NetworkCredential(proxyUserName, proxyUserPwd, proxyUserDomain); return resolver; }

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  • "select * from table" vs "select colA,colB,etc from table" interesting behaviour in SqlServer2005

    - by kristof
    Apology for a lengthy post but I needed to post some code to illustrate the problem. Inspired by the question What is the reason not to use select * ? posted a few minutes ago, I decided to point out some observations of the select * behaviour that I noticed some time ago. So let's the code speak for itself: IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[starTest]') AND type in (N'U')) DROP TABLE [dbo].[starTest] CREATE TABLE [dbo].[starTest]( [id] [int] IDENTITY(1,1) NOT NULL, [A] [varchar](50) NULL, [B] [varchar](50) NULL, [C] [varchar](50) NULL ) ON [PRIMARY] GO insert into dbo.starTest(a,b,c) select 'a1','b1','c1' union all select 'a2','b2','c2' union all select 'a3','b3','c3' go IF EXISTS (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[vStartest]')) DROP VIEW [dbo].[vStartest] go create view dbo.vStartest as select * from dbo.starTest go go IF EXISTS (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[vExplicittest]')) DROP VIEW [dbo].[vExplicittest] go create view dbo.[vExplicittest] as select a,b,c from dbo.starTest go select a,b,c from dbo.vStartest select a,b,c from dbo.vExplicitTest IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[starTest]') AND type in (N'U')) DROP TABLE [dbo].[starTest] CREATE TABLE [dbo].[starTest]( [id] [int] IDENTITY(1,1) NOT NULL, [A] [varchar](50) NULL, [B] [varchar](50) NULL, [D] [varchar](50) NULL, [C] [varchar](50) NULL ) ON [PRIMARY] GO insert into dbo.starTest(a,b,d,c) select 'a1','b1','d1','c1' union all select 'a2','b2','d2','c2' union all select 'a3','b3','d3','c3' select a,b,c from dbo.vExplicittest select a,b,c from dbo.vStartest If you execute the following query and look at the results of last 2 select statements, the results that you will see will be as follows: select a,b,c from dbo.vExplicittest a1 b1 c1 a2 b2 c2 a3 b3 c3 select a,b,c from dbo.vStartest a1 b1 d1 a2 b2 d2 a3 b3 d3 As you can see in the results of select a,b,c from dbo.vStartest the data of column c has been replaced with the data from colum d. I believe that is related to the way the views are compiled, my understanding is that the columns are mapped by column indexes (1,2,3,4) as apposed to names. I though I would post it as a warning for people using select * in their sql and experiencing unexpected behaviour. Note: If you rebuild the view that uses select * each time after you modify the table it will work as expected

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  • cfchart ignores my scalefrom value

    - by Monte Chan
    Hi all, I have the following codes in my page. The style variable holds the custom style. <cfchart chartheight="450" chartwidth="550" gridlines="9" yaxistitle="Score" scalefrom="20" scaleto="100" style="#style#" format="png" > <cfchartseries query="variables.chart_query" type="scatter" seriescolor="##000000" itemcolumn="MyItem" valuecolumn="MyScore"/> </cfchart> Before I begin, please go to http://www.monteandjanicechan.com/chart_good.jpg. This is how I want my report to come up. On the x-axis, there will always be three items as long as at least one of them has values. If an item does not have any values (i.e. 2010), there would not be a marker in the chart. The problem occurs only when only one item has value. Please see http://www.monteandjanicechan.com/chart_bad.jpg. As you can see, 2008 and 2010 do not have any values; y-axis is now scaled from 0 to 100. I have tried setting one of the items (ex. 2008) a value of 0 or something off the chart; it would scale according to this off-the-chart value and the 2009 value. In short, I have to have at least two items with values between 20 and 100 in order for cfchart to scale from 20 to 100. My question is, how can I correct the issue so that cfchart would ALWAYS scale from 20 to 100? I am running CF9. Thanks in advance, Monte

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  • How do we greatly optimize our MySQL database (or replace it) when using joins?

    - by jkaz
    Hi there, This is the first time I'm approaching an extremely high-volume situation. This is an ad server based on MySQL. However, the query that is used incorporates a lot of JOINs and is generally just slow. (This is Rails ActiveRecord, btw) sel = Ads.find(:all, :select = '*', :joins = "JOIN campaigns ON ads.campaign_id = campaigns.id JOIN users ON campaigns.user_id = users.id LEFT JOIN countries ON countries.campaign_id = campaigns.id LEFT JOIN keywords ON keywords.campaign_id = campaigns.id", :conditions = [flashstr + "keywords.word = ? AND ads.format = ? AND campaigns.cenabled = 1 AND (countries.country IS NULL OR countries.country = ?) AND ads.enabled = 1 AND campaigns.dailyenabled = 1 AND users.uenabled = 1", kw, format, viewer['country'][0]], :order = order, :limit = limit) My questions: Is there an alternative database like MySQL that has JOIN support, but is much faster? (I know there's Postgre, still evaluating it.) Otherwise, would firing up a MySQL instance, loading a local database into memory and re-loading that every 5 minutes help? Otherwise, is there any way I could switch this entire operation to Redis or Cassandra, and somehow change the JOIN behavior to match the (non-JOIN-able) nature of NoSQL? Thank you!

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  • ASP.NET MVC2 custom rolemanager (webconfig problem)

    - by ile
    Structure of the web: SAMembershipProvider.cs namespace User.Membership { public class SAMembershipProvider : MembershipProvider { #region - Properties - private int NewPasswordLength { get; set; } private string ConnectionString { get; set; } //private MachineKeySection MachineKey { get; set; } //Used when determining encryption key values. public bool enablePasswordReset { get; set; } public bool enablePasswordRetrieval { get; set; } public bool requiresQuestionAndAnswer { get; set; } public bool requiresUniqueEmail { get; set; } public int maxInvalidPasswordAttempts { get; set; } public int passwordAttemptWindow { get; set; } public MembershipPasswordFormat passwordFormat { get; set; } public int minRequiredNonAlphanumericCharacters { get; set; } public int minRequiredPasswordLength { get; set; } public string passwordStrengthRegularExpression { get; set; } public override string ApplicationName { get; set; } // Indicates whether passwords can be retrieved using the provider's GetPassword method. // This property is read-only. public override bool EnablePasswordRetrieval { get { return enablePasswordRetrieval; } } // Indicates whether passwords can be reset using the provider's ResetPassword method. // This property is read-only. public override bool EnablePasswordReset { get { return enablePasswordReset; } } // Indicates whether a password answer must be supplied when calling the provider's GetPassword and ResetPassword methods. // This property is read-only. public override bool RequiresQuestionAndAnswer { get { return requiresQuestionAndAnswer; } } public override int MaxInvalidPasswordAttempts { get { return maxInvalidPasswordAttempts; } } // For a description, see MaxInvalidPasswordAttempts. // This property is read-only. public override int PasswordAttemptWindow { get { return passwordAttemptWindow; } } // Indicates whether each registered user must have a unique e-mail address. // This property is read-only. public override bool RequiresUniqueEmail { get { return requiresUniqueEmail; } } public override MembershipPasswordFormat PasswordFormat { get { return passwordFormat; } } // The minimum number of characters required in a password. // This property is read-only. public override int MinRequiredPasswordLength { get { return minRequiredPasswordLength; } } // The minimum number of non-alphanumeric characters required in a password. // This property is read-only. public override int MinRequiredNonAlphanumericCharacters { get { return minRequiredNonAlphanumericCharacters; } } // A regular expression specifying a pattern to which passwords must conform. // This property is read-only. public override string PasswordStrengthRegularExpression { get { return passwordStrengthRegularExpression; } } #endregion #region - Methods - public override void Initialize(string name, NameValueCollection config) { throw new NotImplementedException(); } public override bool ChangePassword(string username, string oldPassword, string newPassword) { throw new NotImplementedException(); } public override bool ChangePasswordQuestionAndAnswer(string username, string password, string newPasswordQuestion, string newPasswordAnswer) { throw new NotImplementedException(); } // Takes, as input, a user name, password, e-mail address, and other information and adds a new user // to the membership data source. CreateUser returns a MembershipUser object representing the newly // created user. It also accepts an out parameter (in Visual Basic, ByRef) that returns a // MembershipCreateStatus value indicating whether the user was successfully created or, if the user // was not created, the reason why. If the user was not created, CreateUser returns null. // Before creating a new user, CreateUser calls the provider's virtual OnValidatingPassword method to // validate the supplied password. It then creates the user or cancels the action based on the outcome of the call. public override MembershipUser CreateUser(string username, string password, string email, string passwordQuestion, string passwordAnswer, bool isApproved, object providerUserKey, out MembershipCreateStatus status) { throw new NotImplementedException(); } public override bool DeleteUser(string username, bool deleteAllRelatedData) { throw new NotImplementedException(); } public override MembershipUserCollection FindUsersByEmail(string emailToMatch, int pageIndex, int pageSize, out int totalRecords) { throw new NotImplementedException(); } // Returns a MembershipUserCollection containing MembershipUser objects representing users whose user names // match the usernameToMatch input parameter. Wildcard syntax is data source-dependent. MembershipUser objects // in the MembershipUserCollection are sorted by user name. If FindUsersByName finds no matching users, it // returns an empty MembershipUserCollection. // For an explanation of the pageIndex, pageSize, and totalRecords parameters, see the GetAllUsers method. public override MembershipUserCollection FindUsersByName(string usernameToMatch, int pageIndex, int pageSize, out int totalRecords) { throw new NotImplementedException(); } // Returns a MembershipUserCollection containing MembershipUser objects representing all registered users. If // there are no registered users, GetAllUsers returns an empty MembershipUserCollection // The results returned by GetAllUsers are constrained by the pageIndex and pageSize input parameters. pageSize // specifies the maximum number of MembershipUser objects to return. pageIndex identifies which page of results // to return. Page indexes are 0-based. // // GetAllUsers also takes an out parameter (in Visual Basic, ByRef) named totalRecords that, on return, holds // a count of all registered users. public override MembershipUserCollection GetAllUsers(int pageIndex, int pageSize, out int totalRecords) { throw new NotImplementedException(); } // Returns a count of users that are currently online-that is, whose LastActivityDate is greater than the current // date and time minus the value of the membership service's UserIsOnlineTimeWindow property, which can be read // from Membership.UserIsOnlineTimeWindow. UserIsOnlineTimeWindow specifies a time in minutes and is set using // the <membership> element's userIsOnlineTimeWindow attribute. public override int GetNumberOfUsersOnline() { throw new NotImplementedException(); } // Takes, as input, a user name and a password answer and returns that user's password. If the user name is not // valid, GetPassword throws a ProviderException. // Before retrieving a password, GetPassword verifies that EnablePasswordRetrieval is true. If // EnablePasswordRetrieval is false, GetPassword throws a NotSupportedException. If EnablePasswordRetrieval is // true but the password format is hashed, GetPassword throws a ProviderException since hashed passwords cannot, // by definition, be retrieved. A membership provider should also throw a ProviderException from Initialize if // EnablePasswordRetrieval is true but the password format is hashed. // // GetPassword also checks the value of the RequiresQuestionAndAnswer property before retrieving a password. If // RequiresQuestionAndAnswer is true, GetPassword compares the supplied password answer to the stored password // answer and throws a MembershipPasswordException if the two don't match. GetPassword also throws a // MembershipPasswordException if the user whose password is being retrieved is currently locked out. public override string GetPassword(string username, string answer) { throw new NotImplementedException(); } // Takes, as input, a user name or user ID (the method is overloaded) and a Boolean value indicating whether // to update the user's LastActivityDate to show that the user is currently online. GetUser returns a MembershipUser // object representing the specified user. If the user name or user ID is invalid (that is, if it doesn't represent // a registered user) GetUser returns null (Nothing in Visual Basic). public override MembershipUser GetUser(object providerUserKey, bool userIsOnline) { throw new NotImplementedException(); } // Takes, as input, a user name or user ID (the method is overloaded) and a Boolean value indicating whether to // update the user's LastActivityDate to show that the user is currently online. GetUser returns a MembershipUser // object representing the specified user. If the user name or user ID is invalid (that is, if it doesn't represent // a registered user) GetUser returns null (Nothing in Visual Basic). public override MembershipUser GetUser(string username, bool userIsOnline) { throw new NotImplementedException(); } // Takes, as input, an e-mail address and returns the first registered user name whose e-mail address matches the // one supplied. // If it doesn't find a user with a matching e-mail address, GetUserNameByEmail returns an empty string. public override string GetUserNameByEmail(string email) { throw new NotImplementedException(); } // Virtual method called when a password is created. The default implementation in MembershipProvider fires a // ValidatingPassword event, so be sure to call the base class's OnValidatingPassword method if you override // this method. The ValidatingPassword event allows applications to apply additional tests to passwords by // registering event handlers. // A custom provider's CreateUser, ChangePassword, and ResetPassword methods (in short, all methods that record // new passwords) should call this method. protected override void OnValidatingPassword(ValidatePasswordEventArgs e) { base.OnValidatingPassword(e); } // Takes, as input, a user name and a password answer and replaces the user's current password with a new, random // password. ResetPassword then returns the new password. A convenient mechanism for generating a random password // is the Membership.GeneratePassword method. // If the user name is not valid, ResetPassword throws a ProviderException. ResetPassword also checks the value of // the RequiresQuestionAndAnswer property before resetting a password. If RequiresQuestionAndAnswer is true, // ResetPassword compares the supplied password answer to the stored password answer and throws a // MembershipPasswordException if the two don't match. // // Before resetting a password, ResetPassword verifies that EnablePasswordReset is true. If EnablePasswordReset is // false, ResetPassword throws a NotSupportedException. If the user whose password is being changed is currently // locked out, ResetPassword throws a MembershipPasswordException. // // Before resetting a password, ResetPassword calls the provider's virtual OnValidatingPassword method to validate // the new password. It then resets the password or cancels the action based on the outcome of the call. If the new // password is invalid, ResetPassword throws a ProviderException. // // Following a successful password reset, ResetPassword updates the user's LastPasswordChangedDate. public override string ResetPassword(string username, string answer) { throw new NotImplementedException(); } // Unlocks (that is, restores login privileges for) the specified user. UnlockUser returns true if the user is // successfully unlocked. Otherwise, it returns false. If the user is already unlocked, UnlockUser simply returns true. public override bool UnlockUser(string userName) { throw new NotImplementedException(); } // Takes, as input, a MembershipUser object representing a registered user and updates the information stored for // that user in the membership data source. If any of the input submitted in the MembershipUser object is not valid, // UpdateUser throws a ProviderException. // Note that UpdateUser is not obligated to allow all the data that can be encapsulated in a MembershipUser object to // be updated in the data source. public override void UpdateUser(MembershipUser user) { throw new NotImplementedException(); } // Takes, as input, a user name and a password and verifies that they are valid-that is, that the membership data // source contains a matching user name and password. ValidateUser returns true if the user name and password are // valid, if the user is approved (that is, if MembershipUser.IsApproved is true), and if the user isn't currently // locked out. Otherwise, it returns false. // Following a successful validation, ValidateUser updates the user's LastLoginDate and fires an // AuditMembershipAuthenticationSuccess Web event. Following a failed validation, it fires an // // AuditMembershipAuthenticationFailure Web event. public override bool ValidateUser(string username, string password) { throw new NotImplementedException(); //if (string.IsNullOrEmpty(password.Trim())) return false; //string hash = EncryptPassword(password); //User user = _repository.GetByUserName(username); //if (user == null) return false; //if (user.Password == hash) //{ // User = user; // return true; //} //return false; } #endregion /// <summary> /// Procuses an MD5 hash string of the password /// </summary> /// <param name="password">password to hash</param> /// <returns>MD5 Hash string</returns> protected string EncryptPassword(string password) { //we use codepage 1252 because that is what sql server uses byte[] pwdBytes = Encoding.GetEncoding(1252).GetBytes(password); byte[] hashBytes = System.Security.Cryptography.MD5.Create().ComputeHash(pwdBytes); return Encoding.GetEncoding(1252).GetString(hashBytes); } } // End Class } SARoleProvider.cs namespace User.Membership { public class SARoleProvider : RoleProvider { #region - Properties - // The name of the application using the role provider. ApplicationName is used to scope // role data so that applications can choose whether to share role data with other applications. // This property can be read and written. public override string ApplicationName { get; set; } #endregion #region - Methods - public override void Initialize(string name, NameValueCollection config) { throw new NotImplementedException(); } // Takes, as input, a list of user names and a list of role names and adds the specified users to // the specified roles. // AddUsersToRoles throws a ProviderException if any of the user names or role names do not exist. // If any user name or role name is null (Nothing in Visual Basic), AddUsersToRoles throws an // ArgumentNullException. If any user name or role name is an empty string, AddUsersToRoles throws // an ArgumentException. public override void AddUsersToRoles(string[] usernames, string[] roleNames) { throw new NotImplementedException(); } // Takes, as input, a role name and creates the specified role. // CreateRole throws a ProviderException if the role already exists, the role name contains a comma, // or the role name exceeds the maximum length allowed by the data source. public override void CreateRole(string roleName) { throw new NotImplementedException(); } // Takes, as input, a role name and a Boolean value that indicates whether to throw an exception if there // are users currently associated with the role, and then deletes the specified role. // If the throwOnPopulatedRole input parameter is true and the specified role has one or more members, // DeleteRole throws a ProviderException and does not delete the role. If throwOnPopulatedRole is false, // DeleteRole deletes the role whether it is empty or not. // // When DeleteRole deletes a role and there are users assigned to that role, it also removes users from the role. public override bool DeleteRole(string roleName, bool throwOnPopulatedRole) { throw new NotImplementedException(); } // Takes, as input, a search pattern and a role name and returns a list of users belonging to the specified role // whose user names match the pattern. Wildcard syntax is data-source-dependent and may vary from provider to // provider. User names are returned in alphabetical order. // If the search finds no matches, FindUsersInRole returns an empty string array (a string array with no elements). // If the role does not exist, FindUsersInRole throws a ProviderException. public override string[] FindUsersInRole(string roleName, string usernameToMatch) { throw new NotImplementedException(); } // Returns the names of all existing roles. If no roles exist, GetAllRoles returns an empty string array (a string // array with no elements). public override string[] GetAllRoles() { throw new NotImplementedException(); } // Takes, as input, a user name and returns the names of the roles to which the user belongs. // If the user is not assigned to any roles, GetRolesForUser returns an empty string array // (a string array with no elements). If the user name does not exist, GetRolesForUser throws a // ProviderException. public override string[] GetRolesForUser(string username) { throw new NotImplementedException(); //User user = _repository.GetByUserName(username); //string[] roles = new string[user.Role.Rights.Count + 1]; //roles[0] = user.Role.Description; //int idx = 0; //foreach (Right right in user.Role.Rights) // roles[++idx] = right.Description; //return roles; } public override string[] GetUsersInRole(string roleName) { throw new NotImplementedException(); } // Takes, as input, a role name and returns the names of all users assigned to that role. // If no users are associated with the specified role, GetUserInRole returns an empty string array (a string array with // no elements). If the role does not exist, GetUsersInRole throws a ProviderException. public override bool IsUserInRole(string username, string roleName) { throw new NotImplementedException(); //User user = _repository.GetByUserName(username); //if (user != null) // return user.IsInRole(roleName); //else // return false; } // Takes, as input, a list of user names and a list of role names and removes the specified users from the specified roles. // RemoveUsersFromRoles throws a ProviderException if any of the users or roles do not exist, or if any user specified // in the call does not belong to the role from which he or she is being removed. public override void RemoveUsersFromRoles(string[] usernames, string[] roleNames) { throw new NotImplementedException(); } // Takes, as input, a role name and determines whether the role exists. public override bool RoleExists(string roleName) { throw new NotImplementedException(); } #endregion } // End Class } From Web.config: <membership defaultProvider="SAMembershipProvider" userIsOnlineTimeWindow="15"> <providers> <clear/> <add name="SAMembershipProvider" type="User.Membership.SAMembershipProvider, User" /> </providers> </membership> <roleManager defaultProvider="SARoleProvider" enabled="true" cacheRolesInCookie="true"> <providers> <clear/> <add name="SARoleProvider" type="User.Membership.SARoleProvider" /> </providers> </roleManager> When running project, I get following error: Server Error in '/' Application. Configuration Error Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately. Parser Error Message: The method or operation is not implemented. Source Error: Line 71: <providers> Line 72: <clear/> Line 73: <add name="SARoleProvider" type="User.Membership.SARoleProvider" /> Line 74: </providers> Line 75: </roleManager> I tried: <add name="SARoleProvider" type="User.Membership.SARoleProvider, User" /> and <add name="SARoleProvider" type="User.Membership.SARoleProvider, SARoleProvider" /> and <add name="SARoleProvider" type="User.Membership.SARoleProvider, User.Membership" /> but none works Any idea what's wrong here? Thanks, Ile

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  • What Language Feature Can You Just Not Live Without?

    - by akdom
    I always miss python's built-in doc strings when working in other languages. I know this may seem odd, but it allows me to cut down significantly on excess comments while still providing a clean description of my code and any interfaces therein. What Language Feature Can You Just Not Live Without? If someone were building a new language and they asked you what one feature they absolutely must include, what would it be? This is getting kind of long, so I figured I'd do my best to summarize: Paraphrased to be language agnostic. If you know of a language which uses something mentioned, please at it in the parenthesis to the right of the feature. And if you have a better format for this list, by all means try it out (if it doesn't seem to work, I'll just roll back). Regular Expressions ~ torial (Perl) Garbage Collection ~ SaaS Developer (Python, Perl, Ruby, Java, .NET) Anonymous Functions ~ Vinko Vrsalovic (Lisp, Python) Arithmetic Operators ~ Jeremy Ross (Python, Perl, Ruby, Java, C#, Visual Basic, C, C++, Pascal, Smalltalk, etc.) Exception Handling ~ torial (Python, Java, .NET) Pass By Reference ~ Chris (Python) Unified String Format WalloWizard (C#) Generics ~ torial (Python, Java, C#) Integrated Query Equivalent to LINQ ~ Vyrotek (C#) Namespacing ~ Garry Shutler () Short Circuit Logic ~ Adam Bellaire ()

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  • php get, random records, and the back button

    - by Andrew Heath
    My site has a library full of games, nations, game scenarios, etc. library.php is given a type=___ & id=___ for example library.php?type=scenario&id=ABCD001 library.php saves the id to a session variable and loads an include appropriate for the type This all works just dandy. Now, I wanted to give my users the option of pulling up a random scenario. To do that, I added a special id to the logic within lib-scenario.php (the include) such that if given library.php?type=scenario&id=random the include knows to run an alternate query for a random record rather than for the actual id This also works just dandy... unless someone hits the Random Scenario button two+ times in a row, and decides that the previous random scenario was way cooler, I want to go back to that. Because the http address is always directory/library.php?type=scenario&id=random no matter how many times you click Random Scenario, as soon as you click back you'll be taken to the last page with an alternate address you visited. So, if you start at the Home page, and hit Random Scenario 35 times, then decide the 34th one was what you wanted and click BACK, you'll be put back onto the Home page. I must admit this was not a problem I had anticipated. One of my testers was the first to have the urge to back-up in the random scenario stream and here we are. How can I add back-up functionality to my script?

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  • Should I have different models and views for no user data than for some user data?

    - by Sam Holder
    I'm just starting to learn asp.net mvc and I'm not sure what the right thing to do is. I have a user and a user has a collection of (0 or more) reminders. I have a controller for the user which gets the reminders for the currently logged in user from a reminder service. It populates a model which holds some information about the user and the collection of reminders. My question is should I have 2 different views, one for when there are no reminders and one for when there are some reminders? Or should I have 1 view which checks the number of reminders and displays different things? Having one view seems wrong as then I end up with code in my view which says if (Model.Reminders.Count==0){//do something} else {do something else}, and having logic in the view feels wrong. But if I want to have 2 different views then I'd like to have some code like this in my controller: [Authorize] public ActionResult Index() { MembershipUser currentUser = m_membershipService.GetUser(); IList<Reminder> reminders = m_reminderRepository.GetReminders(currentUser); if (reminders.Count == 0) { var model = new EmptyReminderModel { Email = currentUser.Email, UserName = currentUser.UserName }; return View(model); } else { var model = new ReminderModel { Email = currentUser.Email, UserName = currentUser.UserName, Reminders = reminders }; return View(model); } but obviously this doesn't compile as the View can't take both different types. So if I'm going to do this should I return a specific named view from my controller, depending on the emptiness of the reminders, or should my Index() method redirect to other actions like so: [Authorize] public ActionResult Index() { MembershipUser currentUser = m_membershipService.GetUser(); IList<Reminder> reminders = m_reminderRepository.GetReminders(currentUser); if (reminders.Count == 0) { return RedirectToAction("ShowEmptyReminders"); } else { return RedirectToAction("ShowReminders"); } } which seems nicer but then I need to re-query the reminders for the current user in the ShowReminders action. Or should I be doing something else entirely?

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  • What's the fastest way to get CRUD over CGI on a database handle in Perl?

    - by mithaldu
    TL;DR: Want to write CGI::CRUD::Simple (a minimalist interface module for CGI::CRUD), but I want to check first if i overlooked a module that already does that. I usually work with applications that don't have the niceties of having frameworks and such already in place. However, a while ago i found myself in a situation where i was asking myself: "Self, i have a DBI database handle and a CGI query object, isn't there a module somewhere that can use this to give me some CRUD so i can move on and work on other things instead of spending hours writing an interface?" A quick survey on CPAN gave me: CGI::Crud Catalyst::Plugin::CRUD Gantry::Plugins::CRUD Jifty::View::Declare::CRUD CatalystX::CRUD Catalyst::Controller::CRUD CatalystX::CRUD::REST Catalyst::Enzyme Now, I didn't go particularly in-depth when looking at these modules, but, safe the first one, they all seem to require the presence of some sort of framework. Please tell me if i was wrong and i can just plug any of those into a barebones CGI script. CGI::CRUD seemed to do exactly what i wanted, although it did insist on being used through a rather old and C-like script that must be acquired on a different site and then prodded in various ways and manners to produce something useful. I went with that and found that it works pretty neat and that it should be rather easy to write a simple and easy-to-use module that provides a very basic [dbh, cgi IN]-[html OUT] interface to it. However, as my previous survey was rather short and i may have been hasty in dismissing modules or missed others, i find myself wondering whether that would only be duplication of work already done. As such i ponder the question in the title. PS: I tend to be too short in some of my explanations and make too many assumptions that others think about things similarly as me, resulting in leaving out critical details. If you find yourself wondering just what exactly I am thinking about when i say CRUD, please poke me in comments and I'll amend the question.

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  • "Replay" the steps needed to recreate an error

    - by David
    I am going to create a typical business application that will be used by a few hundred consultants. Normally, the consultants would be presented with an error message with a standard text. As the application will be a complicated one with lots of changes being made to it constantly I would like the following: When an error message is presented, the user has the option to "send" the error message to the developers. The developers should be able to open the incoming file in i.e. Eclipse and debug the steps of the last 10 minutes of work step by step (one line at a time if they want to). Everything should be transparent, meaning that they for example should be able to see the return values of calls to the database. Are there any solutions that offer such functionality today, my preferred language is Python or also Java. I know that there will be a huge performance hit because of such functionality, but that is acceptable as this kind of software is not performance sensitive. It would be VERY nice if the database also had a cronology so that one could query the database for values that existed at the exact time that a specific line of code was run in the application, leading up to the bug.

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  • SQL INSTR() using CSV. Need exact match rather than part

    - by Alastair Pitts
    This is a follow up issue relating to the answer for http://stackoverflow.com/questions/2445029/sql-placeholder-in-where-in-issue-inserted-strings-fail Quick background: We have a SQL query that uses a placeholder value to accept a string, which represents a unique tag/id. Usually, this is only a single tag, but we needed the ability to use a csv string for multiple tags, returning a combined result. In the answer we received from the vendor, they suggested the use of the INSTR function, ala: select * from pitotal where tag IN (SELECT tag from pipoint WHERE INSTR(?, tag) <> 0) and time between 'y' and 't' This works perfectly well 99% of the time, the issue is when the tag is also a subset of 2 parts of the CSV string. Eg the placeholder value is: 'northdom,southdom,eastdom,westdom' and possible tags include: north or northdom What happens, as north is a subset of northdom, is that the two tags are return instead of just northdom, which is actually what we want. I'm not strong on SQL so I couldn't work out how to set it as exact, or split the csv string, so help would be appreciated. Is there a way to split the csv string or make it look for an exact match?

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  • twitter bootstrap typeahead (method 'toLowerCase' of undefined)

    - by mmoscosa
    I am trying to use twitter bootstrap to get the manufacturers from my DB. Because twitter bootstrap typeahead does not support ajax calls I am using this fork: https://gist.github.com/1866577 In that page there is this comment that mentions how to do exactly what I want to do. The problem is when I run my code I keep on getting: Uncaught TypeError: Cannot call method 'toLowerCase' of undefined I googled around and came tried changing my jquery file to both using the minified and non minified as well as the one hosted on google code and I kept getting the same error. My code currently is as follows: $('#manufacturer').typeahead({ source: function(typeahead, query){ $.ajax({ url: window.location.origin+"/bows/get_manufacturers.json", type: "POST", data: "", dataType: "JSON", async: false, success: function(results){ var manufacturers = new Array; $.map(results.data.manufacturers, function(data, item){ var group; group = { manufacturer_id: data.Manufacturer.id, manufacturer: data.Manufacturer.manufacturer }; manufacturers.push(group); }); typeahead.process(manufacturers); } }); }, property: 'name', items:11, onselect: function (obj) { } }); on the url field I added the window.location.origin to avoid any problems as already discussed on another question Also before I was using $.each() and then decided to use $.map() as recomended Tomislav Markovski in a similar question Anyone has any idea why I keep getting this problem?! Thank you

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  • How do you concat multiple rows into one column in SQL Server?

    - by Jason
    I've searched high and low for the answer to this, but I can't figure it out. I'm relatively new to SQL Server and don't quite have the syntax down yet. I have this datastructure (simplified): Table "Users" | Table "Tags": UserID UserName | TagID UserID PhotoID 1 Bob | 1 1 1 2 Bill | 2 2 1 3 Jane | 3 3 1 4 Sam | 4 2 2 ----------------------------------------------------- Table "Photos": | Table "Albums": PhotoID UserID AlbumID | AlbumID UserID 1 1 1 | 1 1 2 1 1 | 2 3 3 1 1 | 3 2 4 3 2 | 5 3 2 | I'm looking for a way to get the all the photo info (easy) plus all the tags for that photo concatenated like CONCAT(username, ', ') AS Tags of course with the last comma removed. I'm having a bear of a time trying to do this. I've tried the method in this article but I get an error when I try to run the query saying that I can't use DECLARE statements... do you guys have any idea how this can be done? I'm using VS08 and whatever DB is installed in it (I normally use MySQL so I don't know what flavor of DB this really is... it's an .mdf file?)

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  • Should I allow sending complete structures when using PUT for updates in a REST API or not?

    - by dafmetal
    I am designing a REST API and I wonder what the recommended way to handle updates to resources would be. More specifically, I would allow updates through a PUT on the resource, but what should I allow in the body of the PUT request? Always the complete structure of the resource? Always the subpart (that changed) of the structure of the resource? A combination of both? For example, take the resource http://example.org/api/v1/dogs/packs/p1. A GET on this resource would give the following: Request: GET http://example.org/api/v1/dogs/packs/p1 Accept: application/xml Response: <pack> <owner>David</owner> <dogs> <dog> <name>Woofer</name> <breed>Basset Hound</breed> </dog> <dog> <name>Mr. Bones</name> <breed>Basset Hound</breed> </dog> </dogs> </pack> Suppose I want to add a dog (Sniffers the Basset Hound) to the pack, would I support either: Request: PUT http://example.org/api/v1/dogs/packs/p1 <dog> <name>Sniffers</name> <breed>Basset Hound</breed> </dog> Response: HTTP/1.1 200 OK or Request: PUT http://example.org/api/v1/dogs/packs/p1 <pack> <owner>David</owner> <dogs> <dog> <name>Woofer</name> <breed>Basset Hound</breed> </dog> <dog> <name>Mr. Bones</name> <breed>Basset Hound</breed> </dog> <dog> <name>Sniffers</name> <breed>Basset Hound</breed> </dog> </dogs> </pack> Response: HTTP/1.1 200 OK or both? If supporting updates through subsections of the structure is recommended, how would I handle deletes (such as when a dog dies)? Through query parameters?

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  • Corrupted mysql table, cause crash in mysql.h (c++)

    - by Francesco
    i've created a very simple mysql class in c+, but when happen that mysql crash , indexes of tables become corrupted, and all my c++ programs crash too because seems that are unable to recognize corrupted table and allowing me to handle the issue .. Q_RES = mysql_real_query(MY_mysql, tmp_query.c_str(), (unsigned int) tmp_query.size()); if (Q_RES != 0) { if (Q_RES == CR_COMMANDS_OUT_OF_SYNC) cout << "errorquery : CR_COMMANDS_OUT_OF_SYNC " << endl; if (Q_RES == CR_SERVER_GONE_ERROR) cout << "errorquery : CR_SERVER_GONE_ERROR " << endl; if (Q_RES == CR_SERVER_LOST) cout << "errorquery : CR_SERVER_LOST " << endl; LAST_ERROR = mysql_error(MY_mysql); if (n_retrycount < n_retry_limit) { // RETRY! n_retrycount++; sleep(1); cout << "SLEEP - query retry! " << endl; ping(); return select_sql(tmp_query); } return false; } MY_result = mysql_store_result(MY_mysql); B_stored_results = true; cout << "b8" << endl; LAST_affected_rows = (mysql_num_rows(MY_result) + 1); // coult return -1 cout << "b8-1" << endl; the program terminate with a "segmentation fault" after doing the "b8" and before the "b8-1" , Q_RES have no issue even if the table is corrupted.. i would like to know if there is a way to recognize that the table have problems and so then i can run a mysql repair or mysql check .. thanks, Francesco

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  • How can I read a DBF file with incorrectly defined column data types using ADO.NET?

    - by Jason
    I have a several DBF files generated by a third party that I need to be able to query. I am having trouble because all of the column types have been defined as characters, but the data within some of these fields actually contain binary data. If I try to read these fields using an OleDbDataReader as anything other than a string or character array, I get an InvalidCastException thrown, but I need to be able to read them as a binary value or at least cast/convert them after they are read. The columns that actually DO contain text are being returned as expected. For example, the very first column is defined as a character field with a length of 2 bytes, but the field contains a 16-bit integer. I have written the following test code to read the first column and convert it to the appropriate data type, but the value is not coming out right. The first row of the database has a value of 17365 (0x43D5) in the first column. Running the following code, what I end up getting is 17215 (0x433F). I'm pretty sure it has to do with using the ASCII encoding to get the bytes from the string returned by the data reader, but I'm not sure of another way to get the value into the format that I need, other that to write my own DBF reader and bypass ADO.NET altogether which I don't want to do unless I absolutely have to. Any help would be greatly appreciated. byte[] c0; int i0; string con = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\ASTM;Extended Properties=dBASE III;User ID=Admin;Password=;"; using (OleDbConnection c = new OleDbConnection(con)) { c.Open(); OleDbCommand cmd = c.CreateCommand(); cmd.CommandText = "SELECT * FROM astm2007"; OleDbDataReader dr = cmd.ExecuteReader(); while (dr.Read()) { c0 = Encoding.ASCII.GetBytes(dr.GetValue(0).ToString()); i0 = BitConverter.ToInt16(c0, 0); } dr.Dispose(); }

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  • Database migration pattern for Java?

    - by Eno
    Im working on some database migration code in Java. Im also using a factory pattern so I can use different kinds of databases. And each kind of database im using implements a common interface. What I would like to do is have a migration check that is internal to the class and runs some database schema update code automatically. The actual update is pretty straight forward (I check schema version in a table and compare against a constant in my app to decide whether to migrate or not and between which versions of schema). To make this automatic I was thinking the test should live inside (or be called from) the constructor. OK, fair enough, that's simple enough. My problem is that I dont want the test to run every single time I instantiate a database object (it runs a query so having it run on every construction is not efficient). So maybe this should be a class static method? I guess my question is, what is a good design pattern for this type of problem? There ought to be a clean way to ensure the migration test runs only once OR is super-efficient.

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  • [NSFetchedResultsController sections] returns nil?

    - by Chris
    Hi Everyone, I am trying to resolve this for days at this stage and I'm hoping you can help. I have two ViewControllers which query two different tables from the same database using Core Data. The first ViewController is opened with the app and displays fine. The second is called from within the first ViewController, using a pretty standard fetch setup: - (NSFetchedResultsController *)fetchedClients { // Set up the fetched results controller if needed. if (fetchedClients == nil) { // Create the fetch request for the entity. NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; // Edit the entity name as appropriate. NSEntityDescription *entity = [NSEntityDescription entityForName:@"Clients" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; // Edit the sort key as appropriate. NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"clientsName" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; // Edit the section name key path and cache name if appropriate. // nil for section name key path means "no sections". NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:nil cacheName:@"Root"]; aFetchedResultsController.delegate = self; self.fetchedClients = aFetchedResultsController; [aFetchedResultsController release]; [fetchRequest release]; [sortDescriptor release]; [sortDescriptors release]; } return fetchedClients; } When I call [self.fetchedClients sections], I get a nil (0x0) return. I have examined the database using an external application to ensure data exists in the "Clients" table. Can anyone think of a reason why [self.fetchedClients sections] would return nil? Many thanks for any help you can provide. Regards, Chris

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  • Converting a Linq expression tree that relies on SqlMethods.Like() for use with the Entity Framework

    - by JohnnyO
    I recently switched from using Linq to Sql to the Entity Framework. One of the things that I've been really struggling with is getting a general purpose IQueryable extension method that was built for Linq to Sql to work with the Entity Framework. This extension method has a dependency on the Like() method of SqlMethods, which is Linq to Sql specific. What I really like about this extension method is that it allows me to dynamically construct a Sql Like statement on any object at runtime, by simply passing in a property name (as string) and a query clause (also as string). Such an extension method is very convenient for using grids like flexigrid or jqgrid. Here is the Linq to Sql version (taken from this tutorial: http://www.codeproject.com/KB/aspnet/MVCFlexigrid.aspx): public static IQueryable<T> Like<T>(this IQueryable<T> source, string propertyName, string keyword) { var type = typeof(T); var property = type.GetProperty(propertyName); var parameter = Expression.Parameter(type, "p"); var propertyAccess = Expression.MakeMemberAccess(parameter, property); var constant = Expression.Constant("%" + keyword + "%"); var like = typeof(SqlMethods).GetMethod("Like", new Type[] { typeof(string), typeof(string) }); MethodCallExpression methodExp = Expression.Call(null, like, propertyAccess, constant); Expression<Func<T, bool>> lambda = Expression.Lambda<Func<T, bool>>(methodExp, parameter); return source.Where(lambda); } With this extension method, I can simply do the following: someList.Like("FirstName", "mike"); or anotherList.Like("ProductName", "widget"); Is there an equivalent way to do this with Entity Framework? Thanks in advance.

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  • Which non-clustered index should I use?

    - by Junior Mayhé
    Here I am studying nonclustered indexes on SQL Server Management Studio. I've created a table with more than 1 million records. This table has a primary key. CREATE TABLE [dbo].[Customers]( [CustomerId] [int] IDENTITY(1,1) NOT NULL, [CustomerName] [varchar](100) NOT NULL, [Deleted] [bit] NOT NULL, [Active] [bit] NOT NULL, CONSTRAINT [PK_Customers] PRIMARY KEY CLUSTERED ( [CustomerId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] This is the query I'll be using to see what execution plan is showing: SELECT CustomerName FROM Customers Well, executing this command with no additional non-clustered index, it leads the execution plan to show me: I/O cost = 3.45646 Operator cost = 4.57715 Now I'm trying to see if it's possible to improve performance, so I've created a non-clustered index for this table: 1) First non-clustered index CREATE NONCLUSTERED INDEX [IX_CustomerID_CustomerName] ON [dbo].[Customers] ( [CustomerId] ASC, [CustomerName] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] GO Executing again the select against Customers table, the execution plan shows me: I/O cost = 2.79942 Operator cost = 3.92001 It seems better. Now I've deleted this just created non-clustered index, in order to create a new one: 2) First non-clustered index CREATE NONCLUSTERED INDEX [IX_CustomerIDIncludeCustomerName] ON [dbo].[Customers] ( [CustomerId] ASC ) INCLUDE ( [CustomerName]) WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] GO With this new non-clustered index, I've executed the select statement again and the execution plan shows me the same result: I/O cost = 2.79942 Operator cost = 3.92001 So, which non-clustered index should I use? Why the costs are the same on execution plan for I/O and Operator? Am I doing something wrong or this is expected? thank you

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  • Kohana 3 ORM: How to get data from pivot table? and all other tables for that matter

    - by zenna
    I am trying to use ORM to access data stored, in three mysql tables 'users', 'items', and a pivot table for the many-many relationship: 'user_item' I followed the guidance from http://stackoverflow.com/questions/1946357/kohana-3-orm-read-additional-columns-in-pivot-tables and tried $user = ORM::factory('user',1); $user->items->find_all(); $user_item = ORM::factory('user_item', array('user_id' => $user, 'item_id' => $user->items)); if ($user_item->loaded()) { foreach ($user_item as $pivot) { print_r($pivot); } } But I get the SQL error: "Unknown column 'user_item.id' in 'order clause' [ SELECT user_item.* FROM user_item WHERE user_id = '1' AND item_id = '' ORDER BY user_item.id ASC LIMIT 1 ]" Which is clearly erroneous because Kohana is trying to order the elements by a column which doesn't exist: user_item.id. This id doesnt exist because the primary keys of this pivot table are the foreign keys of the two other tables, 'users' and 'items'. Trying to use: $user_item = ORM::factory('user_item', array('user_id' => $user, 'item_id' => $user->items)) ->order_by('item_id', 'ASC'); Makes no difference, as it seems the order_by() or any sql queries are ignored if the second argument of the factory is given. Another obvious error with that query is that the item_id = '', when it should contain all the elements. So my question is how can I get access to the data stored in the pivot table, and actually how can I get access to the all items held by a particular user as I even had problems with that? Thanks

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  • Instantiate type variable in Haskell

    - by danportin
    EDIT: Solved. I was unware that enabling a language extension in the source file did not enable the language extension in GHCi. The solution was to :set FlexibleContexts in GHCi. I recently discovered that type declarations in classes and instances in Haskell are Horn clauses. So I encoded the arithmetic operations from The Art of Prolog, Chapter 3, into Haskell. For instance: fac(0,s(0)). fac(s(N),F) :- fac(N,X), mult(s(N),X,F). class Fac x y | x -> y instance Fac Z (S Z) instance (Fac n x, Mult (S n) x f) => Fac (S n) f pow(s(X),0,0) :- nat(X). pow(0,s(X),s(0)) :- nat(X). pow(s(N),X,Y) :- pow(N,X,Z), mult(Z,X,Y). class Pow x y z | x y -> z instance (N n) => Pow (S n) Z Z instance (N n) => Pow Z (S n) (S Z) instance (Pow n x z, Mult z x y) => Pow (S n) x y In Prolog, values are insantiated for (logic) variable in a proof. However, I don't understand how to instantiate type variables in Haskell. That is, I don't understand what the Haskell equivalent of a Prolog query ?-f(X1,X2,...,Xn) is. I assume that :t undefined :: (f x1 x2 ... xn) => xi would cause Haskell to instantiate xi, but this gives a Non type-variable argument in the constraint error, even with FlexibleContexts enabled.

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  • Javascript closures with google geocoder

    - by DaNieL
    Hi all, i still have some problems with javascript closures, and input/output variables. Im playing with google maps api for a no profit project: users will place the marker into a gmap, and I have to save the locality (with coordinates) in my db. The problem comes when i need to do a second geocode in order to get a unique pairs of lat and lng for a location: lets say two users place the marker in the same town but in different places, I dont want to have the same locality twice in the database with differents coords. I know i can do the second geocode after the user select the locality, but i want to understand what am i mistaking here: // First geocoding, take the marker coords to get locality. geocoder.geocode( { 'latLng': new google.maps.LatLng($("#lat").val(), $("#lng").val()), 'language': 'it' }, function(results_1, status_1){ // initialize the html var inside this closure var html = ''; if(status_1 == google.maps.GeocoderStatus.OK) { // do stuff here for(i = 0, geolen = results_1[0].address_components.length; i != geolen) { // Second type of geocoding: for each location from the first geocoding, // i want to have a unique [lat,lan] geocoder.geocode( { 'address': results_1[0].address_components[i].long_name }, function(results_2, status_2){ // Here come the problem. I need to have the long_name here, and // 'html' var should increment. coords = results_2[0].geometry.location.toUrlValue(); html += 'some html to let the user choose the locality'; } ); } // Finally, insert the 'html' variable value into my dom... //but it never gets updated! } else { alert("Error from google geocoder:" + status_1) } } ); I tryed with: // Second type of geocoding: for each location from the first geocoding, i want // to have a unique [lat,lan] geocoder.geocode( { 'address': results_1[0].address_components[i].long_name }, (function(results_2, status_2, long_name){ // But in this way i'll never get results_2 or status_2, well, results_2 // get long_name value, status_2 and long_name is undefined. // However, html var is correctly updated. coords = results_2[0].geometry.location.toUrlValue(); html += 'some html to let the user choose the locality'; })(results_1[0].address_components[i].long_name) ); And with: // Second type of geocoding: for each location from the first geocoding, i want to have // a unique [lat,lan] geocoder.geocode( { 'address': results_1[0].address_components[i].long_name }, (function(results_2, status_2, long_name){ // But i get an obvious "results_2 is not defined" error (same for status_2). coords = results_2[0].geometry.location.toUrlValue(); html += 'some html to let the user choose the locality, that can be more than one'; })(results_2, status_2, results_1[0].address_components[i].long_name) ); Any suggestion? EDIT: My problem is how to pass an additional arguments to the geocoder inner function: function(results_2, status_2, long_name){ //[...] } becose if i do that with a clousure, I mess with the original parameters (results_2 and status_2)

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  • Using NHibernate to select entities based on activity of children entities

    - by mannish
    I'm having a case of the Mondays... I need to select blog posts based on recent activity in the post's comments collection (a Post has a List<Comment> property and likewise, a Comment has a Post property, establishing the relationship. I don't want to show the same post twice, and I only need a subset of the entities, not all of the posts. First thought was to grab all posts that have comments, then order those based on the most recent comment. For this to work, I'm pretty sure I'd have to limit the comments for each Post to the first/newest Comment. Last I'd simply take the top 5 (or whatever max results number I want to pass into the method). Second thought would be to grab all of the comments, ordered by CreatedOn, and filter so there's only one Comment per Post. Then return those top (whatever) posts. This seems like the same as the first option, just going through the back door. I've got an ugly, two query option I've got working with some LINQ on the side for filtering, but I know there's a more elegant way to do it in using the NHibernate API. Hoping to see some good ideas here.

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