Hi,
This is my first post, because although you learn a lot from visits this forum, still have not found answer to this problem (apparently simple).
I have a QSqlRelationalTableModel and want to access the index value of the relationship without making a search related model.
For example:

Tables
Qt Code: 
  1. mysql> describe user;
  2. +--------------+-------------+------+-----+---------+-------+
  3. | Field        | Type        | Null | Key | Default | Extra |
  4. +--------------+-------------+------+-----+---------+-------+
  5. | IdCategory   | int(5)      | NO   | MUL | NULL    |       |
  6. | UserName     | varchar(40) | NO   | PRI | NULL    |       |
  7. | IdPerson     | int(11)     | YES  |     | NULL    |       |
  8. +--------------+-------------+------+-----+---------+-------+
  9.  
  10. mysql> describe category;
  11. +--------------+-------------+------+-----+---------+----------------+
  12. | Field        | Type        | Null | Key | Default | Extra          |
  13. +--------------+-------------+------+-----+---------+----------------+
  14. | IdCategory   | int(5)      | NO   | PRI | NULL    | auto_increment |
  15. | NameCategory | varchar(80) | NO   | UNI | NULL    |                |
  16. +--------------+-------------+------+-----+---------+----------------+
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Code
Qt Code: 
  1. QSqlDatabase Connection;
  2.  
  3. Connection = QSqlDatabase::addDatabase("QMYSQL");
  4. Connection.setHostName("192.168.0.21");
  5. Connection.setDatabaseName("brb");
  6. Connection.setUserName("user");
  7. Connection.setPassword("password");
  8.  
  9. Connection.open();
  10.  
  11. // table user
  13. modelUser = new QSqlRelationalTableModel;
  14. modelUser->setTable("user");
  15. modelUser->sort(modelUser->fieldIndex("UserName"), Qt::AscendingOrder);
  16. modelUser->setRelation(modelUser->fieldIndex("IdCategory"), QSqlRelation("category", "IdCategory", "NameCategory"));
  17. modelUser->select();
  18.  
  19. // table category
  20. QSqlTableModel* Category;
  21. Category = new QSqlTableModel;
  22. Category->setTable("category");
  23. Category->select();
  24.  
  25. int i, j;
  26. for(i = 0; i < 3; 
  27.   for(j = 0; j < modelUser->record().count(); j++)
  28.     qDebug()<<modelUser->record(i).fieldName(j)<<" :"<<modelUser->record(i).value(j).toString();
  29.  
  30. qDebug()<<modelUser->record(0).value("IdCategory").toString();
  31. qDebug()<<modelUser->record(1).value("IdCategory").toString();
  32. qDebug()<<modelUser->record(2).value("IdCategory").toString();
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Application output:
Qt Code: 
  1. Starting C:\Qt\2010.04\projects\teste-build-desktop\debug\teste.exe...
  2.  
  3. "NameCategory"  : "ADMINISTRATOR" 
  4. "UserName"  : "beatriz" 
  5. "IdPerson"  : "0" 
  6.  
  7. "NameCategory"  : "MANAGER" 
  8. "UserName"  : "ana" 
  9. "IdPerson"  : "0" 
  10.  
  11. "NameCategory"  : "SUPERVISOR" 
  12. "UserName"  : "bob" 
  13. "IdPerson"  : "0" 
  14.  
  15.  
  16. "" 
  17. "" 
  18. ""
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My question is whether it is possible to access the field value user.IdCategory without having to create a search algorithm in the model?
Can someone give me a direction?
The solution to this doubt, not only serves me in this simple example, but it helps me a broader understanding on the very QSqlRelationalTableModel.
My previous experience was with CBuilder / Zeoslib / MySql.
Thank you in advance and excuse my English.