Problem wit 2010.01

[codeman]

Hello friends,

after deinstall 2009.05 and install 2010.01 the qsqltabelmodel in combination with qtableview is still empty. My local Sqlite DB, which I use in my program is fullfilled correct, afterwards I show it in a QTabelview with my QSqlTableModel, but it shows nothing my view is still emty
and model->select() returns false. Have anybody the same problem?? With the 2009.05 everything was ok???

[codeman]

So in addition I do some tests.:

QSqlDatabase db;
    db = QSqlDatabase::database("LocalDB");
    qDebug() << "LocalDB is Valid?:"<< db.isValid();
   QSqlQuery mytest("select * from localDBtable",db);
 
    while(mytest.next())
    {
        qDebug() << mytest.value(2).toString() << endl;
    }
 
    QSqlTableModel mymodel;
    mymodel.setTable("localDBtable");
    bool loctest = mymodel.select();

QSqlDatabase db;
    db = QSqlDatabase::database("LocalDB");
    qDebug() << "LocalDB is Valid?:"<< db.isValid();
   QSqlQuery mytest("select * from localDBtable",db);

    while(mytest.next())
    {
        qDebug() << mytest.value(2).toString() << endl;
    }

    QSqlTableModel mymodel;
    mymodel.setTable("localDBtable");
    bool loctest = mymodel.select();

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So first of all I test the db validation here I get a <true> value
The second I test, if I could trace over a select statement from the table. An I get the value in the while loop. So everything seems ok.
Last I take a QSqlTableModel and try to select() the table, but I get an <false> value.

So I am at the end of my knowledge?
Could anybody image what wrong here???

[wysota]

Did you initialize the database driver properly using QSqlDatabase::addDatabase()? Can we see the exact call?

[tangential]

could you also supply us with the lastError() on the model (after the select?)

if(!loctest)
   qDebug() << mymodel().lastError();

if(!loctest)
   qDebug() << mymodel().lastError();

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[codeman]

@wysota
I have header file with static methods:

/**
 * Static function for databse connection;
 */
//**************************************************************************
static bool createConLocalDb()
//**************************************************************************
{
    QString dbpath;
    dbpath = QCoreApplication::applicationDirPath();
    dbpath.append("/");
    dbpath.append("../db/localdb.db");
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE","LocalDB");
    db.setDatabaseName(dbpath);
    if (!db.open())
    {
         QMessageBox::critical(0, qApp->tr("Cannot open database localdb"),
             qApp->tr("Unable to establish a database connection.\n"
                      "This example needs SQLite support. Please read "
                      "the Qt SQL driver documentation for information how "
                      "to build it.\n\n"
                      "Click Cancel to exit."), QMessageBox::Cancel);
         return false;
    }
    qDebug() << "SQLITE LocalDB" << db.driver();
    qDebug() << "SQLITE LocalDB" << db.driverName();
    qDebug() << "SQLITE LocalDB" << db.connectionName();
    return true;
}
 
 
//**************************************************************************
static bool createConDB2(QString driver= "QODBC",
                             QString connectionstr="DRIVER={SQL Server Native Client 10.0};"
                             "Server=locationToserver;Trusted_Connection=no;"
                             "Database=mydatabasename;Uid=myuid;Pwd=mypass"
                            )
//**************************************************************************
{
    QSqlDatabase db = QSqlDatabase::addDatabase(driver,"DB2");
    db.setDatabaseName(connectionstr);
    if (!db.open()) {
        QSqlError err =  db.lastError ();
        QMessageBox::information(0, QObject::tr("Cannot open database DB2"), err.text());
        return false;
    }
     qDebug() << "MSSQL DB2" << db.driver();
     qDebug() << "MSSQL DB2" << db.driverName();
     qDebug() << "MSSQL DB2" << db.connectionName();
     return true;
}
 
 
//**************************************************************************
static bool createConDummy()
//**************************************************************************
{
    QString dbpath;
    dbpath = QCoreApplication::applicationDirPath();
    dbpath.append("/");
    dbpath.append("../db/dummydb.db");
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
    db.setDatabaseName(dbpath);
    if (!db.open())
    {
         QMessageBox::critical(0, qApp->tr("Cannot open database dummy"),
             qApp->tr("Unable to establish a database connection.\n"
                      "This example needs SQLite support. Please read "
                      "the Qt SQL driver documentation for information how "
                      "to build it.\n\n"
                      "Click Cancel to exit."), QMessageBox::Cancel);
         return false;
    }
    qDebug() << "SQLITE Dummy" << db.driver();
    qDebug() << "SQLITE Dummy" << db.driverName();
    qDebug() << "SQLITE Dummy" << db.connectionName();
    return true;
 
}

/**
 * Static function for databse connection;
 */
//**************************************************************************
static bool createConLocalDb()
//**************************************************************************
{
    QString dbpath;
    dbpath = QCoreApplication::applicationDirPath();
    dbpath.append("/");
    dbpath.append("../db/localdb.db");
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE","LocalDB");
    db.setDatabaseName(dbpath);
    if (!db.open())
    {
         QMessageBox::critical(0, qApp->tr("Cannot open database localdb"),
             qApp->tr("Unable to establish a database connection.\n"
                      "This example needs SQLite support. Please read "
                      "the Qt SQL driver documentation for information how "
                      "to build it.\n\n"
                      "Click Cancel to exit."), QMessageBox::Cancel);
         return false;
    }
    qDebug() << "SQLITE LocalDB" << db.driver();
    qDebug() << "SQLITE LocalDB" << db.driverName();
    qDebug() << "SQLITE LocalDB" << db.connectionName();
    return true;
}


//**************************************************************************
static bool createConDB2(QString driver= "QODBC",
                             QString connectionstr="DRIVER={SQL Server Native Client 10.0};"
                             "Server=locationToserver;Trusted_Connection=no;"
                             "Database=mydatabasename;Uid=myuid;Pwd=mypass"
                            )
//**************************************************************************
{
    QSqlDatabase db = QSqlDatabase::addDatabase(driver,"DB2");
    db.setDatabaseName(connectionstr);
    if (!db.open()) {
        QSqlError err =  db.lastError ();
        QMessageBox::information(0, QObject::tr("Cannot open database DB2"), err.text());
        return false;
    }
     qDebug() << "MSSQL DB2" << db.driver();
     qDebug() << "MSSQL DB2" << db.driverName();
     qDebug() << "MSSQL DB2" << db.connectionName();
     return true;
}


//**************************************************************************
static bool createConDummy()
//**************************************************************************
{
    QString dbpath;
    dbpath = QCoreApplication::applicationDirPath();
    dbpath.append("/");
    dbpath.append("../db/dummydb.db");
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
    db.setDatabaseName(dbpath);
    if (!db.open())
    {
         QMessageBox::critical(0, qApp->tr("Cannot open database dummy"),
             qApp->tr("Unable to establish a database connection.\n"
                      "This example needs SQLite support. Please read "
                      "the Qt SQL driver documentation for information how "
                      "to build it.\n\n"
                      "Click Cancel to exit."), QMessageBox::Cancel);
         return false;
    }
    qDebug() << "SQLITE Dummy" << db.driver();
    qDebug() << "SQLITE Dummy" << db.driverName();
    qDebug() << "SQLITE Dummy" << db.connectionName();
    return true;

}

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After in the constructor I made this:

this->createStatusBar();
    qDebug() << " Creating Connections to Databases";
    int i_conDummy=createConDummy();//"qt_sql_default_connection"
    int i_conlocaldb   = createConLocalDb();//"LocalDB"
    int i_conMssql         = createConDB2();//"DB""
...
...

this->createStatusBar();
    qDebug() << " Creating Connections to Databases";
    int i_conDummy=createConDummy();//"qt_sql_default_connection"
    int i_conlocaldb   = createConLocalDb();//"LocalDB"
    int i_conMssql         = createConDB2();//"DB""
...
...

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The integer values after connection are changed to '1';

After connections to my databses I have this output for the static method I call:

Creating Connections to Databases 
SQLITE Dummy QSQLiteDriver(0x9fff208) 
SQLITE Dummy "QSQLITE" 
SQLITE Dummy "qt_sql_default_connection" 
SQLITE LocalDB QSQLiteDriver(0xa000548) 
SQLITE LocalDB "QSQLITE" 
SQLITE LocalDB "LocalDB" 
MSSQL Proleas QODBCDriver(0xa0016e0) 
MSSQL Proleas "QODBC" 
MSSQL Proleas "DB2"

Creating Connections to Databases 
SQLITE Dummy QSQLiteDriver(0x9fff208) 
SQLITE Dummy "QSQLITE" 
SQLITE Dummy "qt_sql_default_connection" 
SQLITE LocalDB QSQLiteDriver(0xa000548) 
SQLITE LocalDB "QSQLITE" 
SQLITE LocalDB "LocalDB" 
MSSQL Proleas QODBCDriver(0xa0016e0) 
MSSQL Proleas "QODBC" 
MSSQL Proleas "DB2"

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@tangential

could you also supply us with the lastError() on the model (after the select?)

This is the output:

Last Error:  QSqlError(1, "Unable to execute statement", "near ",": syntax error")

Last Error:  QSqlError(1, "Unable to execute statement", "near ",": syntax error")

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@all

with the mssql database I don´t have this select() problem on the modelside !

[wysota]

And how does the main() function look like?

[codeman]

#include <QApplication>
#include <QCoreApplication>
#include <QMainWindow>
 
#include "../headers/tableeditor.h"
 
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Q_INIT_RESOURCE(myresourcefile);
    TableEditor editor;
    editor.showMaximized();
    return app.exec();
}

#include <QApplication>
#include <QCoreApplication>
#include <QMainWindow>

#include "../headers/tableeditor.h"


int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Q_INIT_RESOURCE(myresourcefile);
    TableEditor editor;
    editor.showMaximized();
    return app.exec();
}

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This is my main.cpp

[wysota]

So where do you create those connections? Also please inject the following code after each statement of the code you pasted in post #5 of this thread that operates on the database (creates it, queries it, operates on an sql model) and show us results:

qDebug() << db.lastError().text();

qDebug() << db.lastError().text();

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[venomj]

I think you should init your model like this

QSqlTableModel *model = new QSqlTableModel(this, QSqlDatabase::database("LocalDB"));

QSqlTableModel *model = new QSqlTableModel(this, QSqlDatabase::database("LocalDB"));

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Since you specified a name for your database connection, you should make sure the model connect to "LocalDB" instead of the default db.

[codeman]

Ok I solve it. I had a folder in my bin folder named "plugins" with the old libs. Sorry sorry for the trouble, shame on me ;o(.
I just forget to change the lib in the folder for deploy purposes....

[codeman]

Another question by the way I don´t want to open new thread.
I have only one error ore misfunction.

When I read from mssql database a field with type decimal,
the line:

QString testdt = q.value(2).toString();

QString testdt = q.value(2).toString();

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return an empty string. In the mssql database the field is filled with 0.24 ???

[codeman]

Thanx, for your attention. I solve it.

In the Docu stands :

Constant Value Description
QSql::LowPrecisionInt32 0x01 Force 32bit integer values. In case of floating point numbers, the fractional part is silently discarded.
QSql::LowPrecisionInt64 0x02 Force 64bit integer values. In case of floating point numbers, the fractional part is silently discarded.
QSql::LowPrecisionDouble 0x04 Force double values.
QSql::HighPrecision 0 The default behavior - try to preserve maximum precision.

High precision is declared here as default, but I must set explicitly the policy to QSql::HighPrecision.

Curious?!

In my Program the default precisionPolicy is QSql::LowPrecisionDouble