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  • JSDoc3: How to document a AMD module that returns a function

    - by Jens Simon
    I'm trying to find a way to document AMD modules using JSDoc3. /** * Module description. * * @module path/to/module */ define(['jquery', 'underscore'], function (jQuery, _) { /** * @param {string} foo Foo-Description * @param {object} bar Bar-Description */ return function (foo, bar) { // insert code here }; }); Sadly none of the patterns listed on http://usejsdoc.org/howto-commonjs-modules.html work for me. How can I generate a proper documentation that lists the parameters and return value of the function exported by the module?

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  • Can I make a LaTeX macro 'return' a filename?

    - by drfrogsplat
    I'm writing my thesis/dissertation and since its an on-going work I don't always have the actual images ready for the figures I put into my document, but for various reasons want to automatically have it substitute a dummy figure in place when the included graphics file doesn't exist. E.g. I can do something like \includegraphics[width=8cm]{\chapdir/figures/fluxcapacitor} (where \chapdir is a macro for my 'current' chapter directory, e.g. \def\chapdir{./ch_timetravel} and if there's no ./ch_timetravel/figures/fluxcapacitor.jpg it'll insert ./commands/dummy.jpg instead. I've structured my macros (perhaps naïvely?) so that I have a macro (\figFileOrDummy) that determines the appropriate file to include by checking if the argument provided to it exists, so that I can call \includegraphics[properties]{\figFileOrDummy{\chapdir/figures/fluxcapacitor}}. Except I'm getting various errors depending on how I try to call this, which seem to suggest that I'm approaching the problem in a fundamentally flawed way as far as 'good LaTeX programming' goes. Here's the macro to check if the file exists (and 'return' either filename or the dummy filename): \newcommand{\figFileOrDummy}[1]{% % Figure base name (no extension) to be used if the file exists \def\fodname{#1}% \def\dummyfig{commands/dummy}% % Check if output is PS (.EPS) or PDF (.JPG/.PDF/.PNG/...) figures \ifx\pdfoutput\undefined% % EPS figures only \IfFileExists{\fodname.eps}{}{\def\fodname{\dummyfig}}% \else% % Check existence of various extensions: PDF, TIF, TIFF, JPG, JPEG, PNG, MPS \def\figtest{0}% flag below compared to this value \IfFileExists{\fodname.pdf}{\def\figfilenamefound{1}}{\def\figfilenamefound{0}}% \IfFileExists{\fodname.jpg}{\def\figfilenamefound{1}}{}% \IfFileExists{\fodname.png}{\def\figfilenamefound{1}}{}% % and so on... % If no files found matching the filename (flag is 0) then use the dummy figure \ifx\figfilenamefound\figtest% \def\fodname{\dummyfig}% \fi% \fi% % 'return' the filename \fodname% }% Alternatively, here's a much simpler version which seems to have similar problems: \newcommand{\figFileOrDummy}[1]{% \def\dummyfig{commands/dummy}% \dummyfig% } The \def commands seems to be processed after the expansion of the macro they're trying to define, so it ends up being \def {commands/dummy}... (note the space after \def) and obviously complains. Also it seems to treat the literal contents of the macro as the filename for \includegraphics, rather than resolving/expanding it first, so complains that the file '\def {commands/dummy}... .png' doesn't exist.. I've tried also doing something like \edef\figfilename{\figFileOrDummy{\chapdir/figures/fluxcapacitor}} to try to force it to make \figfilename hold just the value rather than the full macro, but I get an Undefined control sequence error complaining the variables I'm trying to \def in the \figFileOrDummy macro are undefined. So my question is either How do I make this macro expand properly?; or If this is the wrong way of structuring my macros, how should I actually structure such a macro, in order to be able to insert dummy/real figures automatically?; or Is there a package that already handles this type of thing nicely that I've overlooked? I feel like I'm missing something pretty fundamental here...

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  • Using <input type=file /> with J2EE/MySQL Backend

    - by Mark Hazlett
    Hey everyone, I'm wondering how I can hook up an input type=file to send a picture back to a backend servlet that will eventually be stored in a MySQL database as a BLOB? In other words, how can I upload a picture using the input and send that back to the servlet to insert into the database as a BLOB type? Thanks

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  • SugarmCRM REST API always returns "null"

    - by TuomasR
    I'm trying to test out the SugarCRM REST API, running latest version of CE (6.0.1). It seems that whenever I do a query, the API returns "null", nothing else. If I omit the parameters, then the API returns the API description (which the documentation says it should). I'm trying to perform a login, passing as parameter the method (login), input_type and response_type (json) and rest_data (JSON encoded parameters). The following code does the query: $api_target = "http://example.com/sugarcrm/service/v2/rest.php"; $parameters = json_encode(array( "user_auth" => array( "user_name" => "admin", "password" => md5("adminpassword"), ), "application_name" => "Test", "name_value_list" => array(), )); $postData = http_build_query(array( "method" => "login", "input_type" => "json", "response_type" => "json", "rest_data" => $parameters )); echo $parameters . "\n"; echo $postData . "\n"; echo file_get_contents($api_target, false, stream_context_create(array( "http" => array( "method" => "POST", "header" => "Content-Type: application/x-www-form-urlencoded\r\n", "content" => $postData ) ))) . "\n"; I've tried different variations of parameters and using username instead of user_name, and all provide the same result, just a response "null" and that's it.

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  • Setting 0/1-to-1 relationship in SQLAlchemy?

    - by Timmy
    is there a proper way of setting up a 0/1-to-1 relationship? i want to be able to check if the related item exists without creating it: if item.relationship is None: item.relationship = item2() but it creates the insert statements on the if statement

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  • Serialization Error:Unable to generate a temporary class (result=1).\r\nerror CS0030:- c#

    - by ltech
    Running XSD.exe on my xml to generate C# class. All works well except on this property public DocumentATTRIBUTES[][] Document { get { return this.documentField; } set { this.documentField = value; } } I want to try and use CollectionBase, and this was my attempt public DocumentATTRIBUTESCollection Document { get { return this.documentField; } set { this.documentField = value; } } /// <remarks/> [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)] public partial class DocumentATTRIBUTES { private string _author; private string _maxVersions; private string _summary; /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified)] public string author { get { return _author; } set { _author = value; } } /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified)] public string max_versions { get { return _maxVersions; } set { _maxVersions = value; } } /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified)] public string summary { get { return _summary; } set { _summary = value; } } } public class DocumentAttributeCollection : System.Collections.CollectionBase { public DocumentAttributeCollection() : base() { } public DocumentATTRIBUTES this[int index] { get { return (DocumentATTRIBUTES)this.InnerList[index]; } } public void Insert(int index, DocumentATTRIBUTES value) { this.InnerList.Insert(index, value); } public int Add(DocumentATTRIBUTES value) { return (this.InnerList.Add(value)); } } However when I try to serialize my object using XmlSerializer serializer = new XmlSerializer(typeof(DocumentMetaData)); I get the error: {"Unable to generate a temporary class (result=1).\r\nerror CS0030: Cannot convert type 'DocumentATTRIBUTES' to 'DocumentAttributeCollection'\r\nerror CS1502: The best overloaded method match for 'DocumentAttributeCollection.Add(DocumentATTRIBUTES)' has some invalid arguments\r\nerror CS1503: Argument '1': cannot convert from 'DocumentAttributeCollection' to 'DocumentATTRIBUTES'\r\n"} the XSD pertaining to this property is <xs:complexType> <xs:sequence> <xs:element name="ATTRIBUTES" minOccurs="0" maxOccurs="unbounded"> <xs:complexType> <xs:sequence> <xs:element name="author" type="xs:string" minOccurs="0" /> <xs:element name="max_versions" type="xs:string" minOccurs="0" /> <xs:element name="summary" type="xs:string" minOccurs="0" /> </xs:sequence> </xs:complexType> </xs:element> </xs:sequence> </xs:complexType> </xs:element>

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  • Sort by ranking algorithm using will-paginate

    - by bearwithclaws
    I'm creating a digg-like site using Ruby on Rails that ranks the item (based on this algorithm). I'm using the will-paginate gem list the items in pages. The problem is, will-paginate only allows me to insert ':order =' based on the table data. I would like to make will-paginate to sort by a number which is calculated using a function based on different fields on the table (e.g number of votes, age hours). How can I do that?

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  • SQLAlchemy sessions - DetachedInstanceError?

    - by benjaminhkaiser
    I have a function that attempts to take a list of usernames, look each one up in a user table, and then add them to a membership table. If even one username is invalid, I want the entire list to be rolled back, including any users that have already been processed. I thought that using sessions was the best way to do this but I'm running into a DetachedInstanceError: DetachedInstanceError: Instance <Organization at 0x7fc35cb5df90> is not bound to a Session; attribute refresh operation cannot proceed Full stack trace is here. The error seems to trigger when I attempt to access the user (model) object that is returned by the query. From my reading I understand that it has something to do with there being multiple sessions, but none of the suggestions I saw on other threads worked for me. Code is below: def add_members_in_bulk(organization_eid, users): """Add users to an organization in bulk - helper function for add_member()""" """Returns "success" on success and id of first failed student on failure""" session = query_session.get_session() session.begin_nested() users = users.split('\n') for u in users: try: user = user_lookup.by_student_id(u) except ObjectNotFoundError: session.rollback() return u if user: membership.add_user_to_organization( user.entity_id, organization_eid, '', [] ) session.flush() session.commit() return 'success' here's the membership.add_user_to_organization: def add_user_to_organization(user_eid, organization_eid, title, tag_ids): """Add a User to an Organization with the given title""" user = user_lookup.by_eid(user_eid) organization = organization_lookup.by_eid(organization_eid) new_membership = OrganizationMembership( organization_eid=organization.entity_id, user_eid=user.entity_id, title=title) new_membership.tags = [get_tag_by_id(tag_id) for tag_id in tag_ids] crud.add(new_membership) and here is the lookup by ID query: def by_student_id(student_id, include_disabled=False): """Get User by RIN""" try: return get_query_set(include_disabled).filter(User.student_id == student_id).one() except NoResultFound: raise ObjectNotFoundError("User with RIN %s does not exist." % student_id)

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  • C++ include statement required if defining a map in a headerfile.

    - by Justin
    I was doing a project for computer course on programming concepts. This project was to be completed in C++ using Object Oriented designs we learned throughout the course. Anyhow, I have two files symboltable.h and symboltable.cpp. I want to use a map as the data structure so I define it in the private section of the header file. I #include <map> in the cpp file before I #include "symboltable.h". I get several errors from the compiler (MS VS 2008 Pro) when I go to debug/run the program the first of which is: Error 1 error C2146: syntax error : missing ';' before identifier 'table' c:\users\jsmith\documents\visual studio 2008\projects\project2\project2\symboltable.h 22 Project2 To fix this I had to #include <map> in the header file, which to me seems strange. Here are the relevant code files: // symboltable.h #include <map> class SymbolTable { public: SymbolTable() {} void insert(string variable, double value); double lookUp(string variable); void init(); // Added as part of the spec given in the conference area. private: map<string, double> table; // Our container for variables and their values. }; and // symboltable.cpp #include <map> #include <string> #include <iostream> using namespace std; #include "symboltable.h" void SymbolTable::insert(string variable, double value) { table[variable] = value; // Creates a new map entry, if variable name already exist it overwrites last value. } double SymbolTable::lookUp(string variable) { if(table.find(variable) == table.end()) // Search for the variable, find() returns a position, if thats the end then we didnt find it. throw exception("Error: Uninitialized variable"); else return table[variable]; } void SymbolTable::init() { table.clear(); // Clears the map, removes all elements. }

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  • Library to parse C/C++ source code

    - by John
    Which library should I use to parse C/C++ source code file? I need to parse source file, calculate how much useful strings inside, how much 'for' blocks, 'if' blocks, how much comments inside. I also may need to insert a comment or small piece of code after each 'for' block. Is there any libraries? May be any library included in Microsoft Visual Studio?

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  • Ignore collection properties in PropertyInfo

    - by LukePet
    I have a function with this code: foreach (PropertyInfo propertyInfo in typeof(T).GetProperties()){ //SOME CODE if (propertyInfo.CanWrite) propertyInfo.SetValue(myCopy, propertyInfo.GetValue(obj, null), null); } I would avoid to check "collection" properties; to do this now I have insert this control: if (propertyInfo.PropertyType.Name.Contains("List") || propertyInfo.PropertyType.Name.Contains("Enumerable") || propertyInfo.PropertyType.Name.Contains("Collection")) continue; but, It don't like me! Which is a better way to do it?

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  • Error with connection in my database servlet

    - by Zerobu
    Hello, I am writing a Database servlet, all seems well except that there seems to be an error in my connection import java.io.IOException; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import javax.servlet.RequestDispatcher; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class DBServlet3 extends HttpServlet { private static final long serialVersionUID = 1L; @Override public void init() throws ServletException { super.init(); try { String jdbcDriverClass= getServletContext().getInitParameter( "jdbcDriverClass" ); if (jdbcDriverClass == null) throw new ServletException( "Could not find jdbcDriverClass initialization parameter" ); Class.forName( jdbcDriverClass ); } catch (ClassNotFoundException e) { throw new ServletException( "Could not load JDBC driver class", e ); } } @Override protected void doGet( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { RequestDispatcher dispatcher= request.getRequestDispatcher( "/db.jsp" ); ServletContext application= getServletContext(); ArrayList<String> names= new ArrayList<String>(); try { Connection connection= null; Statement statement= null; ResultSet results= null; try { String jdbcUrl= application.getInitParameter( "jdbcUrl" ); String jdbcUser= application.getInitParameter( "jdbcUser" ); String jdbcPassword= application.getInitParameter( "jdbcPassword" ); connection= DriverManager.getConnection( jdbcUrl, jdbcUser, jdbcPassword ); statement= connection.createStatement(); results= statement.executeQuery( "SELECT * FROM students" ); while (results.next()) { String name= results.getString( "name" ); names.add( name ); } } finally { if (results != null) results.close(); if (statement != null) statement.close(); if (connection != null) connection.close(); } } catch (SQLException e) { throw new ServletException( e ); } request.setAttribute( "names", names ); dispatcher.forward( request, response ); } @Override protected void doPost( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { String sql= "INSERT INTO students VALUES (" + request.getParameter( "id" ) + ", '" + request.getParameter( "name" ) + "')"; sql= "INSERT INTO students VALUES (?, ?, ?, ?)"; PreparedStatement statement= connection.prepareStatement( sql ); //error on this line statement.setString( 1, request.getParameter( "id" ) ); statement.setString( 2, request.getParameter( "name" ) ); } }

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  • How to create an entity with a composite primary key containing a generated value.

    - by David
    Using Hibernate + annotations, I'm trying to do the following: Two entities, Entity1 and Entity2. Entity1 contains a simple generated value primary key. Entity2 primary key is composed by a simple generated value + the id of entity one (with a many to one relationship) Unfortunately, I can't make it work. Here is an excerpt of the code: @Entity public class Entity1 { @Id @GeneratedValue private Long id; private String name; ... } @Entity public class Entity2 { @EmbeddedId private Entity2PK pk = new Entity2PK(); private String miscData; ... } @Embeddable public class Entity2PK implements Serializable { @GeneratedValue private Long id; @ManyToOne private Entity1 entity; } void test() { Entity1 e1 = new Entity1(); e1.setName("nameE1"); Entity2 e2 = new Entity2(); e2.setEntity1(e1); e2.setMiscData("test"); Transaction transaction = session.getTransaction(); try { transaction.begin(); session.save(e1); session.save(e2); transaction.commit(); } catch (Exception e) { transaction.rollback(); } finally { session.close(); } } When I run the test method I get the following errors: Hibernate: insert into Entity1 (id, name) values (null, ?) Hibernate: call identity() Hibernate: insert into Entity2 (miscData, entity_id, id) values (?, ?, ?) 07-Jun-2010 10:51:11 org.hibernate.util.JDBCExceptionReporter logExceptions WARNING: SQL Error: 0, SQLState: null 07-Jun-2010 10:51:11 org.hibernate.util.JDBCExceptionReporter logExceptions SEVERE: failed batch 07-Jun-2010 10:51:11 org.hibernate.event.def.AbstractFlushingEventListener performExecutions SEVERE: Could not synchronize database state with session org.hibernate.exception.GenericJDBCException: Could not execute JDBC batch update at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103) at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91) at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43) at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:254) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:167) at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:298) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1001) at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:339) at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:106) at test.App.main(App.java:32) Caused by: java.sql.BatchUpdateException: failed batch at org.hsqldb.jdbc.jdbcStatement.executeBatch(Unknown Source) at org.hsqldb.jdbc.jdbcPreparedStatement.executeBatch(Unknown Source) at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:48) at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:247) ... 8 more Note that I use HSQLDB. Any ideas about what is wrong ?

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  • How can I determine when an InnoDB table was last changed?

    - by David M
    I've had success in the past storing the (heavily) processed results of a database query in memcached, using the last update time of the underlying tables(s) as part of the cache key. For MyISAM tables, that last changed time is available in SHOW TABLE STATUS. Unfortunately, that's usually NULL for InnoDB tables. In MySQL 4.1, the ctime for an InnoDB in its SHOW TABLE STATUS line was usually its actual last update time, but that doesn't seem to be true for MySQL 5.1. There is a DATETIME field in the table, but it only shows when a row has been modified - it cannot show the deletion time of a row that's not there anymore! So, I really cannot use MAX(update_time). Here's the really tricky part. I have a number of replicas that I do reads from. Can I figure out the state of the table that doesn't rely on when the changes have actually been applied? My conclusion after working on this for a while is that it's not going to be possible to get this information as cheaply as I'd like. I'm probably going to cache data until the time that I expect the table to change (it's updated once a day), and let the query cache help out where it can.

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  • Heroku: Postgres type operator error after migrating DB from MySQL

    - by sevennineteen
    This is a follow-up to a question I'd asked earlier which phrased this as more of a programming problem than a database problem. http://stackoverflow.com/questions/2935985/postgres-error-with-sinatra-haml-datamapper-on-heroku I believe the problem has been isolated to the storage of the ID column in Heroku's Postgres database after running db:push. In short, my app runs properly on my original MySQL database, but throws Postgres errors on Heroku when executing any query on the ID column, which seems to have been stored in Postgres as TEXT even though it is stored as INT in MySQL. My question is why the ID column is being created as INT in Postgres on the data transfer to Heroku, and whether there's any way for me to prevent this. Here's the output from a heroku console session which demonstrates the issue: Ruby console for myapp.heroku.com >> Post.first.title => "Welcome to First!" >> Post.first.title.class => String >> Post.first.id => 1 >> Post.first.id.class => Fixnum >> Post[1] PostgresError: ERROR: operator does not exist: text = integer LINE 1: ...", "title", "created_at" FROM "posts" WHERE ("id" = 1) ORDER... ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. Query: SELECT "id", "name", "email", "url", "title", "created_at" FROM "posts" WHERE ("id" = 1) ORDER BY "id" LIMIT 1 Thanks!

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  • SQL Server Compact Edition - Create Database Tables

    - by Lennie De Villiers
    Hi, I got it right to create a SQL Server CE database table using the code below: string connectionString = "DataSource=\"test.sdf\"; Password=\"mypassword\""; SqlCeEngine en = new SqlCeEngine(connectionString); en.CreateDatabase(); But how do I create my database tables and insert data? I've got the SQL created statements stored in the application Resource location.

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  • Return dataset in dataflow

    - by praveen
    Hi All, Could I get ideas on retrieving the dataset using lookup method. Basically, my scenario as I have source data needs to lookup for other source table and on matching column from source I need to get all the records from other source data. its a one to many relations. I tried Lookup but gives only one record on matching condition, OLE DB command don't retrieve any data as it will do only Insert/Update operations. Thanks prav

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  • Entity Sql Group By problem, please help

    - by Zviadi
    Hello, help me please with this simple E-sql query: var qStr = "SELECT SqlServer.Month(o.DatePaid) as month, SqlServer.Sum(o.PaidMoney) as PaidMoney FROM XACCModel.OrdersIncomes as o group by SqlServer.Month(o.DatePaid)"; heres what I have. I have simple Entity called OrdersIncomes with ID,PaidMoney,DatePaid,Order_ID properties I want to select Month and Summed PaidMoney like this: month Paidmoney 1 500 2 700 3 1200 T-SQL looks like this and works fine: select MONTH(o.DatePaid), SUM(o.PaidMoney) from OrdersIncomes as o group by MONTH(o.DatePaid) results: 3 31.0000 4 127.0000 5 20.0000 (3 row(s) affected) but E-SQL doesnot work and I dont know what to do. here my E-SQL which needs refactoring: var qStr = "SELECT SqlServer.Month(o.DatePaid) as month, SqlServer.Sum(o.PaidMoney) as PaidMoney FROM XACCModel.OrdersIncomes as o group by SqlServer.Month(o.DatePaid)"; theres exception: ErrorDescription = "The identifier 'o' is not valid because it is not contained either in an aggregate function or in the GROUP BY clause." if I include o in group by clause, like: FROM XACCModel.OrdersIncomes as o group by o then I dont get summed and agregated results. is this some bug? or what Im doing wrong. heres Linq to Entities query and it works too: var incomeResult = from ic in _context.OrdersIncomes group ic by ic.DatePaid.Month into gr select new { Month = gr.Key, PaidMoney = gr.Sum(i = i.PaidMoney) };

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  • SQLAlchemy autocommiting?

    - by muckabout
    I have an issue with SQLAlchemy apparently committing. A rough sketch of my code: trans = self.conn.begin() try: assert not self.conn.execute(my_obj.__table__.select(my_obj.id == id)).first() self.conn.execute(my_obj.__table__.insert().values(id=id)) assert not self.conn.execute(my_obj.__table__.select(my_obj.id == id)).first() except: trans.rollback() raise I don't commit, and the second assert always fails! In other words, it seems the data is getting inserted into the database even though the code is within a transaction! Is this assessment accurate?

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  • B-trees, databases, sequential inputs, and speed.

    - by IanC
    I know from experience that b-trees have awful performance when data is added to them sequentially (regardless of the direction). However, when data is added randomly, best performance is obtained. This is easy to demonstrate with the likes of an RB-Tree. Sequential writes cause a maximum number of tree balances to be performed. I know very few databases use binary trees, but rather used n-order balanced trees. I logically assume they suffer a similar fate to binary trees when it comes to sequential inputs. This sparked my curiosity. If this is so, then one could deduce that writing sequential IDs (such as in IDENTITY(1,1)) would cause multiple re-balances of the tree to occur. I have seen many posts argue against GUIDs as "these will cause random writes". I never use GUIDs, but it struck me that this "bad" point was in fact a good point. So I decided to test it. Here is my code: SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[T1]( [ID] [int] NOT NULL CONSTRAINT [T1_1] PRIMARY KEY CLUSTERED ([ID] ASC) ) GO CREATE TABLE [dbo].[T2]( [ID] [uniqueidentifier] NOT NULL CONSTRAINT [T2_1] PRIMARY KEY CLUSTERED ([ID] ASC) ) GO declare @i int, @t1 datetime, @t2 datetime, @t3 datetime, @c char(300) set @t1 = GETDATE() set @i = 1 while @i < 2000 begin insert into T2 values (NEWID(), @c) set @i = @i + 1 end set @t2 = GETDATE() WAITFOR delay '0:0:10' set @t3 = GETDATE() set @i = 1 while @i < 2000 begin insert into T1 values (@i, @c) set @i = @i + 1 end select DATEDIFF(ms, @t1, @t2) AS [Int], DATEDIFF(ms, @t3, getdate()) AS [GUID] drop table T1 drop table T2 Note that I am not subtracting any time for the creation of the GUID nor for the considerably extra size of the row. The results on my machine were as follows: Int: 17,340 ms GUID: 6,746 ms This means that in this test, random inserts of 16 bytes was almost 3 times faster than sequential inserts of 4 bytes. Would anyone like to comment on this? Ps. I get that this isn't a question. It's an invite to discussion, and that is relevant to learning optimum programming.

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