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  • Hibernate Query Language Problem

    - by Sarang
    Well, I have implemented a distinct query in hibernate. It returns me result. But, while casting the fields are getting interchanged. So, it generates casting error. What should be the solution? As an example, I do have database, "ProjectAssignment" that has three fields, aid, pid & userName. I want all distinct userName data from this table. I have applied query : select distinct userName, aid, pid from ProjectAssignment Whereas the ProjectAssignment.java file has the fields in sequence aid, pid & userName. Now, here the userName is first field in output. So, Casting is not getting possible. Also, query : select aid, pid, distinct userName from ProjectAssignment is not working. What is the proper query for the same ? Or what else the solution ? The code is as below : System Utilization Service Bean Method where I have to retrieve data : public List<ProjectAssignment> getProjectAssignments() { projectAssignments = ProjectAssignmentHelper.getAllResources(); //Here comes the error return projectAssignments; } ProjectAssignmentHelper from where I fetch Data : package com.hibernate; import java.util.List; import org.hibernate.Query; import org.hibernate.Session; public class ProjectAssignmentHelper { public static List<ProjectAssignment> getAllResources() { List<ProjectAssignment> projectMasters; Session session = HibernateUtil.getSessionFactory().openSession(); Query query = session.createQuery("select distinct aid, pid, userName from ProjectAssignment"); projectMasters = (List<ProjectAssignment>) query.list(); session.close(); return projectMasters; } } Hibernate Data Bean : package com.hibernate; public class ProjectAssignment implements java.io.Serializable { private short aid; private String pid; private String userName; public ProjectAssignment() { } public ProjectAssignment(short aid) { this.aid = aid; } public ProjectAssignment(short aid, String pid, String userName) { this.aid = aid; this.pid = pid; this.userName = userName; } public short getAid() { return this.aid; } public void setAid(short aid) { this.aid = aid; } public String getPid() { return this.pid; } public void setPid(String pid) { this.pid = pid; } public String getUserName() { return this.userName; } public void setUserName(String userName) { this.userName = userName; } } Error : For input string: "userName" java.lang.NumberFormatException: For input string: "userName" at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48) at java.lang.Integer.parseInt(Integer.java:447) at java.lang.Integer.parseInt(Integer.java:497) at javax.el.ArrayELResolver.toInteger(ArrayELResolver.java:375) at javax.el.ArrayELResolver.getValue(ArrayELResolver.java:195) at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:175) at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:72) at com.sun.el.parser.AstValue.getValue(AstValue.java:116) at com.sun.el.parser.AstValue.getValue(AstValue.java:163) at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:219) at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:102) at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:190) at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:178) at javax.faces.component.UICommand.getValue(UICommand.java:218) at org.primefaces.component.commandlink.CommandLinkRenderer.encodeMarkup(CommandLinkRenderer.java:113) at org.primefaces.component.commandlink.CommandLinkRenderer.encodeEnd(CommandLinkRenderer.java:54) at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:878) at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:70) at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:54) at org.primefaces.component.datatable.DataTableRenderer.encodeTable(DataTableRenderer.java:525) at org.primefaces.component.datatable.DataTableRenderer.encodeMarkup(DataTableRenderer.java:407) at org.primefaces.component.datatable.DataTableRenderer.encodeEnd(DataTableRenderer.java:193) at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:878) at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:70) at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:54) at org.primefaces.component.tabview.TabViewRenderer.encodeContents(TabViewRenderer.java:198) at org.primefaces.component.tabview.TabViewRenderer.encodeMarkup(TabViewRenderer.java:130) at org.primefaces.component.tabview.TabViewRenderer.encodeEnd(TabViewRenderer.java:48) at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:878) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1620) at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:848) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1613) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1616) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1616) at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:380) at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:126) at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:127) at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:313) at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1523) at org.apache.catalina.core.ApplicationDispatcher.doInvoke(ApplicationDispatcher.java:802) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:664) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:497) at org.apache.catalina.core.ApplicationDispatcher.doDispatch(ApplicationDispatcher.java:468) at org.apache.catalina.core.ApplicationDispatcher.dispatch(ApplicationDispatcher.java:364) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:314) at org.apache.jasper.runtime.PageContextImpl.forward(PageContextImpl.java:783) at org.apache.jsp.welcome_jsp._jspService(welcome_jsp.java from :59) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:109) at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:406) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:483) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:373) at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1523) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:188) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:641) at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:97) at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:85) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:185) at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:332) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:233) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:165) at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:791) at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:693) at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:954) at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:170) at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:135) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:102) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:88) at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:76) at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:53) at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57) at com.sun.grizzly.ContextTask.run(ContextTask.java:69) at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:330) at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:309) at java.lang.Thread.run(Thread.java:619)

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  • How to temporarily disable read-only 2nd level cache hibernate strategy in Grails ?

    - by fabien7474
    In my grails application, some of my domain classes will never be changed by Users. However, some maintenance work is sometimes necessary, and administrator should be able to create/edit few instances from time to time (let's say twice a year). I would like to set a read-only 2nd level cache strategy for these domain classes (static mapping = { cache usage: 'read-only' } ) AND I would like to be able to 'disable' (in very particular situations) the read-only strategy in order to udate some instances via Grails scaffolding edit view. Is it possible? What do you advise me to do? EDIT: The solution I am implementing is a mix of Pascal and Burt answers (see comments). Both answers are great and helpful. So I got a dilemna for choosing the accepted answer! Anyway, thank you.

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  • How to use second level cache for lazy loaded collections in Hibernate?

    - by Chandru
    Let's say I have two entities, Employee and Skill. Every employee has a set of skills. Now when I load the skills lazily through the Employee instances the cache is not used for skills in different instances of Employee. Let's Consider the following data set. Employee - 1 : Java, PHP Employee - 2 : Java, PHP When I load Employee - 2 after Employee - 1, I do not want hibernate to hit the database to get the skills and instead use the Skill instances already available in cache. Is this possible? If so how? Hibernate Configuration <session-factory> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.password">pass</property> <property name="hibernate.connection.url">jdbc:mysql://localhost/cache</property> <property name="hibernate.connection.username">root</property> <property name="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</property> <property name="hibernate.cache.use_second_level_cache">true</property> <property name="hibernate.cache.use_query_cache">true</property> <property name="hibernate.cache.provider_class">net.sf.ehcache.hibernate.EhCacheProvider</property> <property name="hibernate.hbm2ddl.auto">update</property> <property name="hibernate.show_sql">true</property> <mapping class="org.cache.models.Employee" /> <mapping class="org.cache.models.Skill" /> </session-factory> The Entities with imports, getters and setters Removed @Entity @Table(name = "employee") @Cache(usage = CacheConcurrencyStrategy.READ_WRITE) public class Employee { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private int id; private String name; public Employee() { } @ManyToMany @JoinTable(name = "employee_skills", joinColumns = @JoinColumn(name = "employee_id"), inverseJoinColumns = @JoinColumn(name = "skill_id")) @Cache(usage = CacheConcurrencyStrategy.READ_WRITE) private List<Skill> skills; } @Entity @Table(name = "skill") @Cache(usage = CacheConcurrencyStrategy.READ_WRITE) public class Skill { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private int id; private String name; } SQL for Loading the Second Employee and his Skills Hibernate: select employee0_.id as id0_0_, employee0_.name as name0_0_ from employee employee0_ where employee0_.id=? Hibernate: select skills0_.employee_id as employee1_1_, skills0_.skill_id as skill2_1_, skill1_.id as id1_0_, skill1_.name as name1_0_ from employee_skills skills0_ left outer join skill skill1_ on skills0_.skill_id=skill1_.id where skills0_.employee_id=? In that I specifically want to avoid the second query as the first one is unavoidable anyway.

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  • Multiple foreign keys to same table using Elixir

    - by Suvir
    Hello, I am new to ORMs in general. I have a table (lets call it Entity) with columns -- ID expression type ( can be 'long_word', 'short_word' or 'sentence' ) Often, the first two types occur in a 'sentence', so, I want to maintain another table which maps 'Sentences' to 'long_word' or 'short_word' using the 'ID' field. All i need is another table with 2 'Integer fields' referring to 'ID' as a foreign key. But, how do i do this in Elixir? Thanks a lot...

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  • Why is an oracle sequence named hibernate_sequence being created with JPA using Hibernate with the O

    - by JavaRocky
    All my entities use this type of @Id @Id @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "MYENTITY_SEQ") @SequenceGenerator(name = "MYENTITY_SEQ", sequenceName = "MYENTITY_SEQ") @Column(name = "MYENTITY", nullable = false) private Long id; Or @Id @Column(name = "MYENTITY") I find that an oracle sequence named hibernate_sequence is always created. Why is this so? And how can i avoid this? I am using JPA1 with Hibernate 3 and the Oracle 10g dialect.

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  • Get children count via HQL

    - by Thomas Lötzer
    Hi, I have a one-to-many mapping between a parent entity and child entities. Now I need to find the number of children associated with each parent for a list of parents. I am trying to do this with HQL but I am not sure how I can get the list of parents in there. Also, I don't know how I can return the entity itself and not just its ID. My current HQL query is: select new map(parent.id as parentId, count(*) as childCount) from Parent parent left join parent.children children group by parent.id but this only returns the ID and does not filter on specific parents. EDIT Based on Pascal's answer I have modified the query to select new map(parent as parent, count(elements(parent.children)) as childCount) from Parent parent group by parent That does work, but is prohibitively slow: 30 seconds instead of 400 ms on the same database.

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  • How Do I Setup NHibernate.Burrow With Fluent?

    - by CalebHC
    I'm very interested in using NHibernate.Burrow for my session handling and DAO in my ASP.NET app but I'm having trouble with the configuration. Burrow requires an XML NHibernate config for setting up its persistence but I don't have a config file since I'm using Fluent NHibernate to generate my config. So is there a way of letting Burrow know of my Fluent configuration? Hope this makes sense. Thanks

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  • Subsonic custom mapping of objects to tables

    - by codekaizen
    Geeting, I'm using Compact Framework 3.5 and have tenatively settled on a custom build of Subsonic 3.0 to do data access. The trouble is that I am used to developing model-first but am also interested in keeping control of my DB schema. Therefore, neither ActiveRecord or Repository appears to meet my needs, and I want to use my existing POCO model and map it to my existing tables. I'm used to doing this via NHibernate and Entity Framework. After some investigation, it appears that I might be able to author a custom QueryMapping to give me the custom mapping I want. Before I start down this path, however, I'd like to see some kind of example of this being done. I can't seem to find any on the web, and wonder if anyone could give input on experience with Subsonic, model-first and a custom Table-per-Type and Table-per-Hierarchy mapping.

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  • JetBrains dotTrace, is it possible to profile source code line by line? else I need another tool

    - by m3ntat
    I am using JetBrains dotTrace, I've profiled my app which is entirely CPU bound. But the results as you walk down the tree don't sum to the level above in the tree, I only see method calls not the body lines of the node in questions method. Is it possible to profile the source code line by line. i.e for one node: SimulatePair() 99.04% --nextUniform() 30.12% --IDCF() 24.08% So the method calls nextUniform + IDCF use 54% of the time in SimulatePair (or 54% total execution time I'm not sure how to read this) regardless what is happening the other 46% of SimulatePair I need some detail on a line by line basis. Any help or alternative tools is much appreciated. Thanks

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  • Importing a SQL Server 2005 Profile Trace Template into SQL 2008

    - by David Stein
    I'm using SQL Server 2008, but my ERP Vendor only offers a SQL 2005 trace template that they'd like me to run on my system. When I attempt to import it, I receive confirmation that it was successfully imported. However, it does not show up in the list of available templates. I've done this on two separate servers to the same effect. Is this a known problem with SQL Server 2008? I Googled unsuccessfully.

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  • using indexer to retrieve Linq to SQL object from datastore

    - by fearofawhackplanet
    class UserDatastore : IUserDatastore { ... public IUser this[Guid userId] { get { User user = (from u in _dataContext.Users where u.Id == userId select u).FirstOrDefault(); return user; } } ... } One of the developers in our team is arguing that an indexer in the above situation is not appropriate and that a GetUser(Guid id) method should be prefered. The arguments being that: 1) We aren't indexing into an in-memory collection, the indexer is basically performing a hidden SQL query 2) Using a Guid in an indexer is bad (FxCop flagged this also) 3) Returning null from an indexer isn't normal behaviour 4) An API user generally wouldn't expect any of this behaviour I agree to an extent with (most of) these points. But I'm also inclined to argue that one of the characteristics of Linq is to abstract the database access to make it appear that you're simply working with a bunch of collections, even though the lazy evaluation paradigm means those collections aren't evaluated until you run a query over them. It doesn't seem inconsistent to me to access the datastore in the same manner as if it was a concrete in-memory collection here. Also bearing in mind this is an inherited codebase which uses this pattern extensively and consistently, is it worth the refactoring? I accept that it might have been better to use a Get method from the start, but I'm not yet convinced that it's completely incorrect to be using an indexer. I'd be interested to hear all opinions, thanks.

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  • Match entities fulfilling filter (strict superset of search)

    - by Jon
    I have an entity (let's say Person) with a set of arbitrary attributes with a known subset of values. I need to search for all of these entities that match all my filter conditions. That is, given a set of Attributes A, I need to find all people that have a set of Attributes that are a superset of A. For example, my table structures look like this: Person: id | name 1 | John Doe 2 | Jane Roe 3 | John Smith Attribute: id | attr_name 1 | Sex 2 | Eye Color ValidValue: id | attr_id | value_name 1 | 1 | Male 2 | 1 | Female 3 | 2 | Blue 4 | 2 | Green 5 | 2 | Brown PersonAttributes id | person_id | attr_id | value_id 1 | 1 | 1 | 1 2 | 1 | 2 | 3 3 | 2 | 1 | 2 4 | 2 | 2 | 4 5 | 3 | 1 | 1 6 | 3 | 2 | 4 In JPA, I have entities built for all of these tables. What I'd like to do is perform a search for all entities matching a given set of attribute-value pairs. For instance, I'd like to be able to find all males (John Doe and John Smith), all people with green eyes (Jane Roe or John Smith), or all females with green eyes (Jane Roe). I see that I can already take advantage of the fact that I only really need to match on value_id, since that's already unique and tied to the attr_id. But where can I go from there? I've been trying to do something like the following, given that the ValidValue is unique in all cases: select distinct p from Person p join p.personAttributes a where a.value IN (:values) Then I've tried putting my set of required values in as "values", but that gives me errors no matter how I try to structure that. I also have to get a little more complicated, as follows, but at this point I'd be happy with solving the first problem cleanly. However, if it's possible, the Attribute table actually has a field for default value: id | attr_name | default_value 1 | Sex | 1 2 | Eye Color | 5 If the value you're searching on happens to be the default value, I want it to return any people that have no explicit value set for that attribute, because in the application logic, that means they inherit the default value. Again, I'm more concerned about the primary question, but if someone who can help with that also has some idea of how to do this one, I'd be extremely grateful.

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  • How to define index by several columns in hibernate entity?

    - by foobar
    Morning. I need to add indexing in hibernate entity. As I know it is possible to do using @Index annotation to specify index for separate column but I need an index for several fields of entity. I've googled and found jboss annotation @Table, that allows to do this (by specification). But (I don't know why) this functionality doesn't work. May be jboss version is lower than necessary, or maybe I don't understant how to use this annotation, but... complex index is not created. Why index may not be created? jboss version 4.2.3.GA Entity example: package somepackage; import org.hibernate.annotations.Index; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.Id; @Entity @org.hibernate.annotations.Table(appliesTo = House.TABLE_NAME, indexes = { @Index(name = "IDX_XDN_DFN", columnNames = {House.XDN, House.DFN} ) } ) public class House { public final static String TABLE_NAME = "house"; public final static String XDN = "xdn"; public final static String DFN = "dfn"; @Id @GeneratedValue private long Id; @Column(name = XDN) private long xdn; @Column(name = DFN) private long dfn; @Column private String address; public long getId() { return Id; } public void setId(long id) { this.Id = id; } public long getXdn() { return xdn; } public void setXdn(long xdn) { this.xdn = xdn; } public long getDfn() { return dfn; } public void setDfn(long dfn) { this.dfn = dfn; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } } When jboss/hibernate tries to create table "house" it throws following exception: Reason: org.hibernate.AnnotationException: @org.hibernate.annotations.Table references an unknown table: house

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  • JPA/Hibernate query with class name?

    - by Petteri Hietavirta
    In this example com.test.Cat extends com.test.Animal and there is no field DB in CAT table of com.test.Cat explicitly defining its type (it wasn't me). When I query my animals from DB I get a collection of Animals. It is possible to sort them by class name: order by r.class but is there a way to use class name as a criteria? For example I would like to get all animals expect dogs. But no luck - even this does not work: where r.class = ? (String "ccc.test.Cat") as I get an exception: Caused by: java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Integer at org.hibernate.type.IntegerType.set(IntegerType.java:64) at org.hibernate.type.NullableType.nullSafeSet(NullableType.java:154) at org.hibernate.type.NullableType.nullSafeSet(NullableType.java:136) at org.hibernate.param.PositionalParameterSpecification.bind(PositionalParameterSpecification.java:62) at org.hibernate.loader.hql.QueryLoader.bindParameterValues(QueryLoader.java:514) at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1589) at org.hibernate.loader.Loader.doQuery(Loader.java:696) at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259) at org.hibernate.loader.Loader.doList(Loader.java:2228) at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125) at org.hibernate.loader.Loader.list(Loader.java:2120) at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401) at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361) at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196) at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148) at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102) at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:67)

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  • Popularity Algorithm - SQL / Django

    - by RadiantHex
    Hi folks, I've been looking into popularity algorithms used on sites such as Reddit, Digg and even Stackoverflow. Reddit algorithm: t = (time of entry post) - (Dec 8, 2005) x = upvotes - downvotes y = {1 if x > 0, 0 if x = 0, -1 if x < 0) z = {1 if x < 0, otherwise x} log(z) + (y * t)/45000 I have always performed simple ordering within SQL, I'm wondering how I should deal with such ordering. Should it be used to define a table, or could I build an SQL with the ordering within the formula (without hindering performance)? I am also wondering, if it is possible to use multiple ordering algorithms in different occasions, without incurring into performance problems. I'm using Django and PostgreSQL. Help would be much appreciated! ^^

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  • What's the best way to calculate similarity between rows in a table based on association?

    - by André Pena
    Suppose each Person has a collection of favorite Books. So I have a table for: Person Book The association between Person and Book (joint table for MxN) I want to fetch the Persons that are similar to a Person1 based on the favorite Books overlaping. That is: The more books they have in common, the more they are similar. I don't have to use only SQL to solve this problem. I could use programming also. I'm using SQL Server 2008 and C#. What solution would you experts use?

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  • bi-directional o2m/m2o beats uni-directional o2m in SQL efficiency?

    - by Henry
    Use these 2 persistent CFCs for example: // Cat.cfc component persistent="true" { property name="id" fieldtype="id" generator="native"; property name="name"; } // Owner.cfc component persistent="true" { property name="id" fieldtype="id" generator="native"; property name="cats" type="array" fieldtype="one-to-many" cfc="cat" cascade="all"; } When one-to-many (unidirectional) Note: inverse=true on unidirectional will yield undesired result: insert into cat (name) values (?) insert into Owner default values update cat set Owner_id=? where id=? When one-to-many/many-to-one (bi-directional, inverse=true on Owner.cats): insert into Owner default values insert into cat (name, ownerId) values (?, ?) Does that mean setting up bi-directional o2m/m2o relationship is preferred 'cause the SQL for inserting the entities is more efficient?

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  • How to make a mapped field inherited from a superclass transient in JPA?

    - by Russ Hayward
    I have a legacy schema that cannot be changed. I am using a base class for the common features and it contains an embedded object. There is a field that is normally mapped in the embedded object that needs to be in the persistence id for only one (of many) subclasses. I have made a new id class that includes it but then I get the error that the field is mapped twice. Here is some example code that is much simplified to maintain the sanity of the reader: @MappedSuperclass class BaseClass { @Embedded private Data data; } @Entity class SubClass extends BaseClass { @EmbeddedId private SubClassId id; } @Embeddable class Data { private int location; private String name; } @Embeddable class SubClassId { private int thingy; private int location; } I have tried @AttributeOverride but I can only get it to rename the field. I have tried to set it to updatable = false, insertable = false but this did not seem to work when used in the @AttributeOverride annotation. See answer below for the solution to this issue. I realise I could change the base class but I really do not want to split up the embedded object to separate the shared field as it would make the surrounding code more complex and require some ugly wrapping code. I could also redesign the whole system for this corner case but I would really rather not. I am using Hibernate as my JPA provider.

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  • versioning fails for onetomany collection holder

    - by Alexander Vasiljev
    given parent entity @Entity public class Expenditure implements Serializable { ... @OneToMany(mappedBy = "expenditure", cascade = CascadeType.ALL, orphanRemoval = true) @OrderBy() private List<ExpenditurePeriod> periods = new ArrayList<ExpenditurePeriod>(); @Version private Integer version = 0; ... } and child one @Entity public class ExpenditurePeriod implements Serializable { ... @ManyToOne @JoinColumn(name="expenditure_id", nullable = false) private Expenditure expenditure; ... } While updating both parent and child in one transaction, org.hibernate.StaleObjectStateException is thrown: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect): Indeed, hibernate issues two sql updates: one changing parent properties and another changing child properties. Do you know a way to get rid of parent update changing child? The update results both in inefficiency and false positive for optimistic lock. Note, that both child and parent save their state in DB correctly. Hibernate version is 3.5.1-Final

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  • PHP ORMs: Doctrine vs. Propel

    - by Tom
    Hi, I'm starting a new project with symfony which is readily integrated with Doctrine and Propel, but I of course need to make a choice.... I was wondering if more experienced people out there have general pros and/or cons for going with either of these two? Thanks a lot. EDIT: Thanks for the all the responses, useful stuff. There's no truly correct answer to this question so I'll just mark as approved the one that got the most popular up-votes.

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  • How do I migrate a ManyToOne to a ManyToMany relationship in Hibernate?

    - by spderosso
    I have a instance field of a class X that is mapped using Hibernate as a Many to One relationship. E.g: public class X{ ... @ManyToOne(optional=false) private Y iField; ... } That is correctly working with a particular schema. I know want to change this instance field iField to a List and a Many to Many relationship. public class X{ ... @ManyToMany(optional=false) private List<Y> iField; ... } What steps should I follow? Do I have to change the schema? in which way? In case you need more info let me know. Thanks!

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  • NHibernate mapping one table on two classes with where selection

    - by Rene Schulte
    We would like to map a single table on two classes with NHibernate. The mapping has to be dynamically depending on the value of a column. Here's a simple example to make it a bit clearer: We have a table called Person with the columns id, Name and Sex. The data from this table should be mapped either on the class Male or on the class Female depending on the value of the column Sex. In Pseudocode: create instance of Male with data from table Person where Person.Sex = 'm'; create instance of Female with data from table Person where Person.Sex = 'f'; The benefit is we have strongly typed domain models and can later avoid switch statements. Is this possible with NHibernate or do we have to map the Person table into a flat Person class first? Then afterwards we would have to use a custom factory method that takes a flat Person instance and returns a Female or Male instance. Would be good if NHibernate (or another library) can handle this.

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