cannot open include file qsqldatabase

Hello. I've tried to right an app with Qt 5.1.1 using sql. When I build my app I get the following error: "Cannot open include file: 'QSqlDatabase': No such file or directory". I've already put the line in the .pro file: QT += sql

Has anyone any ideas what can I do? Thanks in advance.

P.S.: The part of my application with sql code is quite simple:

Code:

---

QSqlDatabase db(QSqlDatabase::addDatabase("QMYSQL"));
 
    //connect to database
    db.setDatabaseName("sarbatori.mwb");
 
    if ( !db.open() )
        QMessageBox::critical(0, "Error", db.lastError().text());
    else
        QMessageBox::information(0, "OK", "Merge!!!");

---

Hello , did you include QtSql in you'r file ?

just a note, dont you need a connection string or a dsn to open the connection with a database ?
something like :

Code:

---

QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
QString servername = "X-PC\\LOCALHOST";
QString dbname = "CARSQL";
QString connTemplate = "DRIVER={SQL SERVER};SERVER=%1;DATABASE=%2;";
QString connectionString = connTemplate.arg(servername).arg(dbname);
db.setDatabaseName(connectionString);

---

or

Code:

---

QSqlDatabase db = QSqlDatabase::addDatabase("QPSQL");
db.setHostName("acidalia");
db.setDatabaseName("customdb");
db.setUserName("mojito");
db.setPassword("J0a1m8");

---

Code:

---

I've already put the line in the .pro file: QT += sql
Has anyone any ideas what can I do?

---

Yes, run qmake after changing the PRO file.

Your "quite simple" code is also unlikely to work when it compiles. A MySQL Workbench file is not a MySQL database.

Quote:

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Originally Posted by ChrisW67

Yes, run qmake after changing the PRO file.

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Thanks. It works. :)

Quote:

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Originally Posted by ChrisW67

Your "quite simple" code is also unlikely to work when it compiles. A MySQL Workbench file is not a MySQL database.

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Thanks. I'm a little new in working with Qt and MySQL. I'll work with the console to create my database. Is there a way to find out in which file the database created is saved?

---

Added after 9 minutes:

Quote:

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Originally Posted by toufic.dbouk

just a note, dont you need a connection string or a dsn to open the connection with a database ?
something like :

Code:

---

QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
QString servername = "X-PC\\LOCALHOST";
QString dbname = "CARSQL";
QString connTemplate = "DRIVER={SQL SERVER};SERVER=%1;DATABASE=%2;";
QString connectionString = connTemplate.arg(servername).arg(dbname);
db.setDatabaseName(connectionString);

---

or

Code:

---

QSqlDatabase db = QSqlDatabase::addDatabase("QPSQL");
db.setHostName("acidalia");
db.setDatabaseName("customdb");
db.setUserName("mojito");
db.setPassword("J0a1m8");

---

---

Well I'm working on localhost and with no password or specific user name. I thought qt will implicit put localhost, root and no password. I have another question: How do you specify to which file the app should connect?

Code:

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QString dbname = "CARSQL"; /* thats the name of your created database */

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in case you want to use a dsn, you can set the database name in the options
for windows:open control panel , go to administrative tools , open Data Sources (ODBC) , add a new system dsn with the specified database and driver (make sure to open the right version 32 or 64-bit
then you can just use:

Code:

---

QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
db.setDatabaseName("yourDSN");

---

Quote:

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Originally Posted by Saurian

Thanks. It works.

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you should always save and rebuild the project for indexing and parsing if you add new code to the .pro file.

Good Luck

Quote:

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Originally Posted by Saurian

I have another question: How do you specify to which file the app should connect?

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Application is connecting to the database not to the file. You must define database name with QSqlDatabase::setDatabaseName method.

Ok. But how does the application know in which file to search the database I specified?

Quote:

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Originally Posted by Saurian

Ok. But how does the application know in which file to search the database I specified?

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Did you read my previous comment ?
And i guess you mean in which location or directory , as Lesiok said its not a file , its a database , i told you 2 ways to do that.
Either you specify the server name and database name your connecting to or you create a DSN
Please read my previous post it clearly explains how to do that almost step by step.
Hope this helps.

Quote:

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Originally Posted by toufic.dbouk

Did you read my previous comment ?
And i guess you mean in which location or directory , as Lesiok said its not a file , its a database , i told you 2 ways to do that.
Either you specify the server name and database name your connecting to or you create a DSN
Please read my previous post it clearly explains how to do that almost step by step.
Hope this helps.

---

Yes, I mean in which location. I want to be able to install this application on any PC and to work there. I want to compile it in Ubuntu too and be able there to make the application work. This is why I would need to know the location so I could zip the database with my application and all it's dll's.

I've wrote the next code:

Code:

---

QSqlDatabase db(QSqlDatabase::addDatabase("QMYSQL"));
 
    //connect to database
    db.setHostName("localhost");
    db.setUserName("username");
    db.setPassword("password");
    db.setDatabaseName("database");
 
 
    if ( !db.open() )
        QMessageBox::critical(0, "Error", db.lastError().text());
    else
        QMessageBox::information(0, "OK", "Merge!!!");

---

and I get the following error box:

"QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QODBC QODBC3 QPSQL QPSQL7"

I've tried to copy libmysql.dll to the folder where my .exe file is and to my qtcreator.exe folder and it's still not working

Quote:

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Originally Posted by Saurian

Yes, I mean in which location.

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it depends on what SQL management application your using. Check your applications guide to find out the location.

Quote:

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Originally Posted by Saurian

YI want to be able to install this application on any PC and to work there. I want to compile it in Ubuntu too and be able there to make the application work.

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im not sure of this , but i would say you have to place the database in your project and specify the path for it

Code:

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QString applicationPath= QApplication::applicationDirPath();/*get the application path*/

---

then append a QDir::separator() , add the database name , and set it to the setDatabaseName(/*QString representing that database path*/)

Quote:

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I've tried to copy libmysql.dll to the folder where my .exe file is and to my qtcreator.exe folder and it's still not working

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place the .dll file in plugins/sqldrivers directory.
you might need more than the .dll file , take a look at this thread http://qt-project.org/forums/viewthread/19122.
you can also try to load QODBC driver since it more of a general driver.
That's my suggestion , but ill wait with your for a reply from a more experienced developer to learn something new.

Quote:

---

Originally Posted by Saurian

Yes, I mean in which location. I want to be able to install this application on any PC and to work there. I want to compile it in Ubuntu too and be able there to make the application work. This is why I would need to know the location so I could zip the database with my application and all it's dll's.

I've wrote the next code:

Code:

---

QSqlDatabase db(QSqlDatabase::addDatabase("QMYSQL"));
 
    //connect to database
    db.setHostName("localhost");
    db.setUserName("username");
    db.setPassword("password");
    db.setDatabaseName("database");
 
 
    if ( !db.open() )
        QMessageBox::critical(0, "Error", db.lastError().text());
    else
        QMessageBox::information(0, "OK", "Merge!!!");

---

and I get the following error box:

"QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QODBC QODBC3 QPSQL QPSQL7"

I've tried to copy libmysql.dll to the folder where my .exe file is and to my qtcreator.exe folder and it's still not working

---

First of all as I see You try to work with MySQL. To work with MySQL database You must install MySQL server and connect to them. Qt application is only a client. If You need to work with small database distributed with application use SQLite.
Second, standard Qt distribution don't contain MySQL driver. You have to build it yourself.