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  • Two collections manyToOne to same primary key

    - by Ethiel
    Hi, guys, I'm coding a web page in Hibernate-JPA and Oracle. I need the following: I have two classes: Place and Home. I need two collections of type Place in every Home: I do the following: Home: @ManyToOne @JoinColumn(name="ID_PLACES") private List<Places>places1; @ManyToOne @JoinColumn(name="ID_PLACES") private List<Places>Places2; However, hibernate got an exception (repeated column) and forces to me to mapping with insert and update to false. How Can I get Two ManyToOne relationship to same primary key with insert a true?.

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  • java will this threading setup work or what can i be doing wrong

    - by Erik
    Im a bit unsure and have to get advice. I have the: public class MyApp extends JFrame{ And from there i do; MyServer = new MyServer (this); MyServer.execute(); MyServer is a: public class MyServer extends SwingWorker<String, Object> { MyServer is doing listen_socket.accept() in the doInBackground() and on connection it create a new class Connection implements Runnable { I have the belove DbHelper that are a singleton. It holds an Sqlite connected. Im initiating it in the above MyApp and passing references all the way in to my runnable: class Connection implements Runnable { My question is what will happen if there are two simultaneous read or `write? My thought here was the all methods in the singleton are synchronized and would put all calls in the queue waiting to get a lock on the synchronized method. Will this work or what can i change? public final class DbHelper { private boolean initalized = false; private String HomePath = ""; private File DBFile; private static final String SYSTEM_TABLE = "systemtable"; Connection con = null; private Statement stmt; private static final ContentProviderHelper instance = new ContentProviderHelper (); public static ContentProviderHelper getInstance() { return instance; } private DbHelper () { if (!initalized) { initDB(); initalized = true; } } private void initDB() { DBFile = locateDBFile(); try { Class.forName("org.sqlite.JDBC"); // create a database connection con = DriverManager.getConnection("jdbc:sqlite:J:/workspace/workComputer/user_ptpp"); } catch (SQLException e) { e.printStackTrace(); } catch (ClassNotFoundException e) { e.printStackTrace(); } } private File locateDBFile() { File f = null; try{ HomePath = System.getProperty("user.dir"); System.out.println("HomePath: " + HomePath); f = new File(HomePath + "/user_ptpp"); if (f.canRead()) return f; else { boolean success = f.createNewFile(); if (success) { System.out.println("File did not exist and was created " + HomePath); // File did not exist and was created } else { System.out.println("File already exists " + HomePath); // File already exists } } } catch (IOException e) { System.out.println("Maybe try a new directory. " + HomePath); //Maybe try a new directory. } return f; } public String getHomePath() { return HomePath; } private synchronized String getDate(){ SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date date = new Date(); return dateFormat.format(date); } public synchronized String getSelectedSystemTableColumn( String column) { String query = "select "+ column + " from " + SYSTEM_TABLE ; try { stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY); ResultSet rs = stmt.executeQuery(query); while (rs.next()) { String value = rs.getString(column); if(value == null || value == "") return ""; else return value; } } catch (SQLException e ) { e.printStackTrace(); return ""; } finally { } return ""; } }

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  • Window's content disappears when minimized

    - by Carmen Cojocaru
    I have a simple class that draws a line when mouse dragging or a dot when mouse pressing(releasing). When I minimize the application and then restore it, the content of the window disappears except the last dot (pixel). I understand that the method super.paint(g) repaints the background every time the window changes, but the result seems to be the same whether I use it or not. The difference between the two of them is that when I don't use it there's more than a pixel painted on the window, but not all my painting. How can I fix this? Here is the class. package painting; import java.awt.*; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.MouseMotionAdapter; import javax.swing.JFrame; import javax.swing.JPanel; class CustomCanvas extends Canvas{ Point oldLocation= new Point(10, 10); Point location= new Point(10, 10); Dimension dimension = new Dimension(2, 2); CustomCanvas(Dimension dimension){ this.dimension = dimension; this.init(); addListeners(); } private void init(){ oldLocation= new Point(0, 0); location= new Point(0, 0); } public void paintLine(){ if ((location.x!=oldLocation.x) || (location.y!=oldLocation.y)) { repaint(location.x,location.y,1,1); } } private void addListeners(){ addMouseListener(new MouseAdapter(){ @Override public void mousePressed(MouseEvent me){ oldLocation = location; location = new Point(me.getX(), me.getY()); paintLine(); } @Override public void mouseReleased(MouseEvent me){ oldLocation = location; location = new Point(me.getX(), me.getY()); paintLine(); } }); addMouseMotionListener(new MouseMotionAdapter() { @Override public void mouseDragged(MouseEvent me){ oldLocation = location; location = new Point(me.getX(), me.getY()); paintLine(); } }); } @Override public void paint(Graphics g){ super.paint(g); g.setColor(Color.red); g.drawLine(location.x, location.y, oldLocation.x, oldLocation.y); } @Override public Dimension getMinimumSize() { return dimension; } @Override public Dimension getPreferredSize() { return dimension; } } class CustomFrame extends JPanel { JPanel displayPanel = new JPanel(new BorderLayout()); CustomCanvas canvas = new CustomCanvas(new Dimension(200, 200)); public CustomFrame(String titlu) { canvas.setBackground(Color.white); displayPanel.add(canvas, BorderLayout.CENTER); this.add(displayPanel); } } public class CustomCanvasFrame { public static void main(String args[]) { CustomFrame panel = new CustomFrame("Test Paint"); JFrame f = new JFrame(); f.add(panel); f.pack(); SwingConsole.run(f, 700, 700); } }

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  • Unable to Use Simple JSOUP Example To Parse Website Table Data

    - by OhNoItsAnOverflow
    I'm attempting to extract the following data from a table via Android / JSOUP however I'm having a bit of trouble nailing down the process. I think I'm getting close to being able to do this using the code I've provided below - but for some reason I still cannot get my textview to display any of the table data. P.S. Live URL's can be provided if necessary. SOURCE: public class MainActivity extends Activity { TextView tv; final String URL = "http://exampleurl.com"; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); tv = (TextView) findViewById(R.id.TextView01); new MyTask().execute(URL); } private class MyTask extends AsyncTask<String, Void, String> { ProgressDialog prog; String title = ""; @Override protected void onPreExecute() { prog = new ProgressDialog(MainActivity.this); prog.setMessage("Loading...."); prog.show(); } @Override protected String doInBackground(String... params) { try { Document doc = Jsoup.connect(params[0]).get(); Element tableElement = doc.getElementsByClass("datagrid") .first(); title = doc.title(); } catch (IOException e) { e.printStackTrace(); } return title; } @Override protected void onPostExecute(String result) { super.onPostExecute(result); prog.dismiss(); tv.setText(result); } } } TABLE: <table class="datagrid"> <tbody><tr> <th>Item No.</th> <th>Name</th> <th>Sex</th> <th>Location</th> </tr> <tr> <td><a href="redirector.cfm?ID=a33660a3-aae0-45e3-9703-d59d77717836&amp;page=1&amp;&amp;lname=&amp;fname=" title="501207593">501207593&nbsp;</a></td> <td>USER1</td> <td>M&nbsp;</td> <td>Unknown</td> </tr> <tr> <td><a href="redirector.cfm?ID=edf524da-8598-450f-9373-da87db8d6c84&amp;page=1&amp;&amp;lname=&amp;fname=" title="501302750">501302750&nbsp;</a></td> <td>USER2</td> <td>M&nbsp;</td> <td>Unknown</td> </tr> <tr> <td><a href="redirector.cfm?ID=a78abeea-7651-4ac1-bba2-0dcb272c8b77&amp;page=1&amp;&amp;lname=&amp;fname=" title="531201804">531201804&nbsp;</a></td> <td>USER3</td> <td>M&nbsp;</td> <td>Unknown</td> </tr> </tbody></table>

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  • copy child collection to another object

    - by Bogdan
    Hi everyone, I have a one-to-many relationship between Part and Params (a "Part" has many "Params). I'm trying to do something naive like this: Part sourcePart = em.find(Part.class, partIdSource); Part destPart = em.find(Part.class, partIdDest); Collection<Param> paramListSource = sourcePart.getParamList(); destPart.setParamList(paramListSource); Basically I want to copy all the parameters from sourcePart to destPart. Hopefully the persistence provider will automatically set the right foreign keys in the Param table/entity. The above code will obviously not work. Is there any easy way of doing this, or do I have to do create a new collection, then add each Param (creating new Param, setting attributes, etc) ?

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  • How to handle Many-To-Many In Grails without belongsTo?

    - by nute
    I need to create a many-to-many relationship in Grails. I have a "Question" domain and a "Tag" domain. A Question can have 0 or more tags. A Tag can have 0 or more Questions. If I put a "hasMany" on each sides, it gives me an error saying I need a "belongTo" somewhere. However, adding a belongsTo means that the owner must exist... Like I said, a Tag could have 0 questions, and a Question could have 0 tags. There is no concept of an owner, it's a many-to-many! What am I supposed to do?

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  • CakePHP hasAndBelongsToMany (HABTM) Delete Joining Record

    - by Jason McCreary
    I have a HABTM relationship between Users and Locations. Both Models have the appropriate $hasAndBelongsToMany variable set. When I managing User Locations, I want to delete the association between the User and Location, but not the Location. Clearly this Location could belong to other users. I would expect the following code to delete just the join table record provided the HABTM associations, but it deleted both records. $this->Weather->deleteAll(array('Weather.id' => $this->data['weather_ids'], false); However, I am new to CakePHP, so I am sure I am missing something. I have tried setting cascade to false and changing the Model order with User, User-Weather, Weather-User. No luck. Thanks in advance for any help.

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  • What techniques are available for filtering collections of objects when using zodb?

    - by Omega
    As the title says: What techniques are available for filtering objects when using zodb? The equivalent in SQL terms would be something like filtering results by a date range. Or only returning rows with a particular value set in a column. If I had a series of blog posts and only wanted ones done in the past month, what would I have to do? Is there any way to optimize these kinds of "queries"? My gut tells me iterating over all the objects in a relationship simply to perform a test is less than optimal.

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  • Merge Primary Keys - Cascade Update

    - by Chris Jackson
    Is there a way to merge two primary keys into one and then cascade update all affected relationships? Here's the scenario: Customers (idCustomer int PK, Company varchar(50), etc) CustomerContacts (idCustomerContact int PK, idCustomer int FK, Name varchar(50), etc) CustomerNotes (idCustomerNote int PK, idCustomer int FK, Note Text, etc) Sometimes customers need to be merged into one. For example, you have a customer with the id of 1 and another with the id of 2. You want to merge both, so that everything that was 2 is now 1. I know I could write a script that updates all affected tables one by one, but I'd like to make it more future proof by using the cascade rules, so I don't have to update the script every time there is a new relationship added. Any ideas?

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  • Limit child rows in Entity Framework Query

    - by Jim
    Hi, If I have a parent and child modelled relationship. How to I select the parent, and some of the child rows. I cannot seem to do it, and load the parent object. var query = ( from parent in Parents.Include("Children") from child in parent.Children where child.Date == parent.Children.Max(x => x.Date) select parent); the problem is that the parent is returned multiple times, not the parent with the children loaded. Is there any way to populate each of the parents, and include the child rows, but only the ones needed. If I try and navigate again, I get all the children, not just the ones with the latest date. Thanks

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  • MySQL count problem

    - by Skuja
    I have 3 tables users(id,name),groups(id,name) and users_groups(user_id,group_id). users and groups have many to many relationship, so the third one is for storing users and groups relations. I would like to select all the data from groups with user count in each group. So far I came up with this: SELECT groups.*, COUNT(users_groups.user_id) AS user_count FROM groups LEFT JOIN users_groups ON users_groups.group_id = groups.id The problem is that query result is not returning any of groups which has no users (users_groups doesnt have any records with group_id of those groups). How should I create my query to select all the groups and they user count, or user count as 0 if there are no users for that group?

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  • Can't send flash message from Model method

    - by Andy
    Hello, I'm trying to prevent a record that has a relationship to another record from being deleted. I can stop the deletion but not send a flash message as I had hoped! class Purchaseitem < ActiveRecord::Base before_destroy :check_if_ingredient ... def check_if_ingredient i = Ingredient.find(:all, :conditions => "purchaseitem_id = #{self.id}") if i.length > 0 self.errors.add(:name) flash.now[:notice] = "#{self.name} is in use as an ingredient and cannot be deleted" return false end end This will prevent a the delete wihthout the flash line, and when I add it I get: undefined local variable or method `flash' for # Any help would be much appreciated!

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  • Entity Framework This property descriptor does not support the SetValue

    - by Gayan
    Hello guys, below are my entities which i have created using entity frame work. retailer id name childs(navigation) generated database schema [Id] [int] IDENTITY(1,1) NOT NULL, [Name] nvarchar NOT NULL childern id name RETAILER(navigation) generated database schema [Id] [int] IDENTITY(1,1) NOT NULL, [name] nvarchar NOT NULL [Retailer_Id] [int] NOT NULL, As you can see in the above model the relationship is 1 retailer can have 0 or 1 child. my problem is when i create a new child and set the retailer navigation property of it to a retailer entity it throws the following exception.how do i solve it Error while setting property 'retailer': 'This property descriptor does not support the SetValue method.'.

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  • non blocking client server chat application in java using nio

    - by Amith
    I built a simple chat application using nio channels. I am very much new to networking as well as threads. This application is for communicating with server (Server / Client chat application). My problem is that multiple clients are not supported by the server. How do I solve this problem? What's the bug in my code? public class Clientcore extends Thread { SelectionKey selkey=null; Selector sckt_manager=null; public void coreClient() { System.out.println("please enter the text"); BufferedReader stdin=new BufferedReader(new InputStreamReader(System.in)); SocketChannel sc = null; try { sc = SocketChannel.open(); sc.configureBlocking(false); sc.connect(new InetSocketAddress(8888)); int i=0; while (!sc.finishConnect()) { } for(int ii=0;ii>-22;ii++) { System.out.println("Enter the text"); String HELLO_REQUEST =stdin.readLine().toString(); if(HELLO_REQUEST.equalsIgnoreCase("end")) { break; } System.out.println("Sending a request to HelloServer"); ByteBuffer buffer = ByteBuffer.wrap(HELLO_REQUEST.getBytes()); sc.write(buffer); } } catch (IOException e) { e.printStackTrace(); } finally { if (sc != null) { try { sc.close(); } catch (Exception e) { e.printStackTrace(); } } } } public void run() { try { coreClient(); } catch(Exception ej) { ej.printStackTrace(); }}} public class ServerCore extends Thread { SelectionKey selkey=null; Selector sckt_manager=null; public void run() { try { coreServer(); } catch(Exception ej) { ej.printStackTrace(); } } private void coreServer() { try { ServerSocketChannel ssc = ServerSocketChannel.open(); try { ssc.socket().bind(new InetSocketAddress(8888)); while (true) { sckt_manager=SelectorProvider.provider().openSelector(); ssc.configureBlocking(false); SocketChannel sc = ssc.accept(); register_server(ssc,SelectionKey.OP_ACCEPT); if (sc == null) { } else { System.out.println("Received an incoming connection from " + sc.socket().getRemoteSocketAddress()); printRequest(sc); System.err.println("testing 1"); String HELLO_REPLY = "Sample Display"; ByteBuffer buffer = ByteBuffer.wrap(HELLO_REPLY.getBytes()); System.err.println("testing 2"); sc.write(buffer); System.err.println("testing 3"); sc.close(); }}} catch (IOException e) { e.printStackTrace(); } finally { if (ssc != null) { try { ssc.close(); } catch (IOException e) { e.printStackTrace(); } } } } catch(Exception E) { System.out.println("Ex in servCORE "+E); } } private static void printRequest(SocketChannel sc) throws IOException { ReadableByteChannel rbc = Channels.newChannel(sc.socket().getInputStream()); WritableByteChannel wbc = Channels.newChannel(System.out); ByteBuffer b = ByteBuffer.allocate(1024); // read 1024 bytes while (rbc.read(b) != -1) { b.flip(); while (b.hasRemaining()) { wbc.write(b); System.out.println(); } b.clear(); } } public void register_server(ServerSocketChannel ssc,int selectionkey_ops)throws Exception { ssc.register(sckt_manager,selectionkey_ops); }} public class HelloClient { public void coreClientChat() { Clientcore t=new Clientcore(); new Thread(t).start(); } public static void main(String[] args)throws Exception { HelloClient cl= new HelloClient(); cl.coreClientChat(); }} public class HelloServer { public void coreServerChat() { ServerCore t=new ServerCore(); new Thread(t).start(); } public static void main(String[] args) { HelloServer st= new HelloServer(); st.coreServerChat(); }}

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  • Hibernate and Child Objects (add versus clear)

    - by tyndall
    Lets say I have domain model with Automobile and Wheels. Wheels is a List of Wheels Wheels has a many-to-one relationship to Automobile. If I get an object back from Hibernate and it has 4 wheels. I take that object remove the 4 wheels and add 4. And then Save. If I ask Hibernate for the object again and it returns an auto with 8 wheels... what are we doing wrong? I don't have access to the source for a few days but want to give our Java devs a push in the right direction. Thanks.

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  • Doctrine 1.2 Column Naming Conventions for Many To Many Relationships

    - by Alan Storm
    I'm working with an existing database schema, and trying to setup two Doctrine models with a Many to Many relationship, as described in this document When creating tables from scratch, I have no trouble getting this working. However, the existing join tables use a different naming convention that what's described in the Doctrine document. Specifically Table 1 -------------------------------------------------- table_1_id ....other columns.... Table 2 -------------------------------------------------- table_2_id ....other columns.... Join Table -------------------------------------------------- fktable1_id fktable_2_id Basically, the previous developers prefaced all forign keys with an fk. From the examples I've seen and some brief experimenting with code, it appears that Doctrine 1.2 requires that the join table use the same column names as the tables it's joining in Is my assumption correct? If so, has the situation changed in Doctrine 2? If the answers to either of the above are true, how do you configure the models so that all the columns "line up"

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  • Drupal Views limiting content posted by group membership

    - by digital
    Hi, I have various different content types and I want to filter by using views. So say a block only displays content posted in groups that you are a member of. I've created my generic view which so far displays all content of that type, but I'm struggling with linking this to content only posted in groups your a member of. I've looked at the Organic Groups filters but no luck there. I suspect I might need to use some sort of relationship but I'm stuck there. Any help would be greatly appreciated.

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  • group_concat on an empty join in MySQL

    - by Yossarian
    Hello, I've got the following problem: I have two tables: (simplified) +--------+ +-----------+ | User | | Role | +--------+ +-----------+ | ID<PK> | | ID <PK> | +--------+ | Name | +-----------+ and M:N relationship between them +-------------+ | User_Role | +-------------+ | User<FK> | | Role<FK> | +-------------+ I need to create a view, which selects me: User, and in one column, all of his Roles (this is done by group_concat). I've tried following: SELECT u.*, group_concat(r.Name separator ',') as Roles FROM User u LEFT JOIN User_Role ur ON ur.User=u.ID LEFT JOIN Role r ON ur.Role=r.ID GROUP BY u.ID; However, this works for an user with some defined roles. Users without role aren't returned. How can I modify the statement, to return me User with empty string in Roles column when User doesn't have any Role? Explanation: I'm passing the SQL data directly to a grid, which then formats itself, and it is easier for me to create slow and complicated view, than to format it in my code. I'm using MySQL

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  • Vim: Custom Folding for special doc

    - by Matthias Guenther
    Here is the code: package localhost import scala.tools.nsc.reporters._ import scala.tools.nsc.util.Position class MyReporter extends Reporter { /** <p> * Give message of an rejected program * </p> */ def info0(pos: Position, msg: String, severity: Severity, force: Boolean) = { severity match { case INFO => case WARNING => case ERROR => println("error on pos: " +pos+" message: "+msg) } } } So I want to to fold /** <p> * Give message of an rejected program * </p> */ to something like: /** */ How is this possible? Thanks for your help.

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  • One to many in nhibernate mapping problem

    - by chobo2
    Hi I have this using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Demo.Framework.Domain { public class UserEntity { public virtual Guid UserId { get; protected set; } } } using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace TDemo.Framework.Domain { public class Users : UserEntity { public virtual string OpenIdIdentifier { get; set; } public virtual string Email { get; set; } public virtual IList<Movie> Movies { get; set; } } } using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Demo.Framework.Domain { public class Movie { public virtual int MovieId { get; set; } public virtual Guid UserId { get; set; } // not sure if I should inherit UserEntity public virtual string Title { get; set; } public virtual DateTime ReleaseDate { get; set; } // in my ms sql 2008 database I want this to be just a Date type. Not sure how to do that. public virtual int Upc { get; set; } } } <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Demo.Framework" namespace="Demo.Framework.Domain"> <class name="Users"> <id name="UserId"> <generator class="guid.comb" /> </id> <property name="OpenIdIdentifier" not-null="true" /> <property name="Email" not-null="true" /> </class> <subclass name="Movie"> <list name="Movies" cascade="all-delete-orphan"> <key column="MovieId" /> <index column="MovieIndex" /> // not sure what index column is really. <one-to-many class="Movie"/> </list> </subclass> </hibernate-mapping> <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Demo.Framework" namespace="Demo.Framework.Domain"> <class name="Movie"> <id name="MovieId"> <generator class="native" /> </id> <property name="Title" not-null="true" /> <property name="ReleaseDate" not-null="true" type="Date" /> <property name="Upc" not-null="true" /> <property name="UserId" not-null="true" type="Guid"/> </class> </hibernate-mapping> I get this error 'extends' attribute is not found or is empty. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: NHibernate.MappingException: 'extends' attribute is not found or is empty. Source Error: Line 17: { Line 18: Line 19: var nhConfig = new Configuration().Configure(); Line 20: var sessionFactory = nhConfig.BuildSessionFactory(); Line 21:

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  • Select an entity according to a list of associated entities

    - by Maverickch
    I have the following database schema : Two tables, books and tags, with n-m relationship. Books - Tags We can have for example the book 1, with tags {A,B,C}, and book 2, with tags {A}. I would like to select the books according to a list of tags. For example : selected tags list : {A,B} - book 1 My idea was to use the MINUS SQL function, to subtract book tags list to the selected tags list, and return the book if the list was empty. Unfortunately, this SQL function is not supported by HQL. Any idea about that ?

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  • d3 tree - parents having same children

    - by Larry Anderson
    I've been transitioning my code from JIT to D3, and working with the tree layout. I've replicated http://mbostock.github.com/d3/talk/20111018/tree.html with my tree data, but I wanted to do a little more. In my case I will need to create child nodes that merge back to form a parent at a lower level, which I realize is more of a directed graph structure, but would like the tree to accomodate (i.e. notice that common id's between child nodes should merge). So basically a tree that divides like normal on the way from parents to children, but then also has the ability to bring those children nodes together to be parents (sort of an incestual relationship or something :)). Asks something similar - How to layout a non-tree hierarchy with D3 It sounds like I might be able to use hierarchical edge bundling in conjunction with the tree hierarchy layout, but I haven't seen that done. I might be a little off with that though.

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  • HQL: illegal attempt to dereference collection

    - by skip
    The situation is like this: I have an entity Book that holds a one-to-many relationship with Chapter. Now if I try the query, "from Book book inner join book.chapters chapter where chapter.title like '%hibernate%'", it gives me the desired result. But if I try, "from Book where book.chapters.title like '%hibernate%'", I get the error illegal attempt to dereference collection. The thing is that I only want the collection of Book objects in return and not a collection of pair of Book and Chapter objects in return which I get with the former query. Could someone help me understand?

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  • Simplest one-to-many Map case in Hibernate doesn't work in MySQL

    - by Malvolio
    I think this is pretty much the simplest case for mapping a Map (that is, an associative array) of entities. @Entity @AccessType("field") class Member { @Id protected long id; @OneToMany(cascade = CascadeType.ALL, fetch=FetchType.LAZY) @MapKey(name = "name") private Map<String, Preferences> preferences = new HashMap<String, Preferences>(); } @Entity @AccessType("field") class Preferences { @ManyToOne Member member; @Column String name; @Column String value; } This looks like it should work, and it does, in HSQL. In MySQL, there are two problems: First, it insists that there be a table called Members_Preferences, as if this were a many-to-many relationship. Second, it just doesn't work: since it never populates Members_Preferences, it never retrieves the Preferences. [My theory is, since I only use HSQL in memory-mode, it automatically creates Members_Preferences and never really has to retrieve the preferences map. In any case, either Hibernate has a huge bug in it or I'm doing something wrong.]

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  • Best way to model Customer <--> Address

    - by Jen
    Every Customer has a physical address and an optional mailing address. What is your preferred way to model this? Option 1. Customer has foreign key to Address Customer (id, phys_address_id, mail_address_id) Address (id, street, city, etc.) Option 2. Customer has one-to-many relationship to Address, which contains a field to describe the address type Customer (id) Address (id, customer_id, address_type, street, city, etc.) Option 3. Address information is de-normalized and stored in Customer Customer (id, phys_street, phys_city, etc. mail_street, mail_city, etc.) One of my overriding goals is to simplify the object-relational mappings, so I'm leaning towards the first approach. What are your thoughts?

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