Error connecting to MySQL

Using Qt-4.1.0 and MySQL 5.0.18

After trying to compile this code:

#include <QApplication>
#include <QtSql>
#include <iostream>
using namespace std;

int main(int argc, char * argv[])
{
cout << "Testing Qt and the connection to the database\n";
QSqlDatabase db = QSqlDatabase::addDatabase("QMySQL");
db.setHostName = ("localhost");
return 1;
}


I get this error:

s/linux-g++ -I. -I../../../include/QtCore -I../../../include/QtGui -I../../../include/QtSql -I../../../include -I. -I. -I. -o qtDatabase.o qtDatabase.cpp
qtDatabase.cpp: In function ‘int main(int, char**)’:
qtDatabase.cpp:11: error: invalid use of member (did you forget the ‘&’ ?)
qtDatabase.cpp: At global scope:
qtDatabase.cpp:6: warning: unused parameter ‘argc’
qtDatabase.cpp:6: warning: unused parameter ‘argv’
make: *** [qtDatabase.o] Error 1


What is wrong with ---- db.setHostName = ("localhost"); ---- ?

For some reason it did not work, but I copy and pasted the code from the website and now it compiled.

The problem now is:

QSqlDatabase: QMYSQL driver not loaded


How do I load it ?

in

Quote:

---

db.setHostName = ("localhost");

---

eliminate the = like in :
db.setHostName("localhost");

Cheers

Quote:

---

QSqlDatabase: QMYSQL driver not loaded
How do I load it ?

---

///check database driver with :
if (!QSqlDatabase::drivers().contains("QMYSQL"))
QMessageBox::critical(this, "Unable to load database", "Needs the QMYSQL driver");

If you get this error message, you probably didn't install the QMYSQL driver.
To install it have a look at the Qt Centre FAQ : Enabling MySQL support

Cheers

I typed:

./configure -qt-sql-mysql

The shell said:

MySQL support cannot be enabled due to functionality tests!

What is wrong ?

Quote:

---

Originally Posted by probine

MySQL support cannot be enabled due to functionality tests!

What is wrong ?

---

You don't have MySQL libraries or you didn't tell Qt where to find them (through -L and -I options).

MySQL is up and running.

What do you mean with libraries ? What libraries ?

Quote:

---

Originally Posted by probine

What do you mean with libraries ? What libraries ?

---

The MySQL client libraries, that allow you to connect to MySQL server. Look for libmysqlclient.so file on your system and make sure you have the headers too.

I installed 2 rpms: "MySQL-server...rpm" and "MySQL-client...rpm", but I cannot find libmysqlclient.so

What am I missing to install ?

Quote:

---

I installed 2 rpms: "MySQL-server...rpm" and "MySQL-client...rpm", but I cannot find libmysqlclient.so

What am I missing to install ?

---

libqt4-mysql.rpm or something like that?
Have a search in your packages.

Quote:

---

Originally Posted by probine

What am I missing to install ?

---

Try mysql-libs and mysql-devel.

This are my packages I haves installed:

[root@dhcp-57106 ~]# rpm -qa | grep mysql
php-mysql-5.0.4-10
mysqlclient10-3.23.58-6
mysql-4.1.11-2
mod_auth_mysql-2.6.1-4
libdbi-dbd-mysql-0.7.1-3
mysql-devel-4.1.11-2
mysql-server-4.1.11-2
mysql-bench-4.1.11-2

I have been trying to find the mysql-libs for FC4, but I cannot...

Do I need something else ? Where can I find the mysql-libs for FC4 ?

Quote:

---

Originally Posted by probine

Do I need something else ? Where can I find the mysql-libs for FC4 ?

---

It's probably a part of other packages. If you have mysql-devel, then it should be already installed.

What does this output?

Code:

---

$ locate mysql.h
$ locate libmysqlclient

---

This is the output of both:

[root@dhcp-57106 Qt-4.1.0]# locate mysql.h
/usr/share/apps/quanta/doc/php/ref.mysql.html
/usr/include/mysql/mysql.h
/usr/local/Trolltech/Qt-4.1.0/src/sql/drivers/mysql/qsql_mysql.h
/usr/local/Trolltech/Qt-4.1.0/include/Qt/qsql_mysql.h
/usr/local/Trolltech/Qt-4.1.0/include/QtSql/qsql_mysql.h
/home/santiago/programs/qt/src/sql/drivers/mysql/qsql_mysql.h
/home/santiago/programs/qt/include/Qt/qsql_mysql.h
/home/santiago/programs/qt/include/QtSql/qsql_mysql.h

[root@dhcp-57106 Qt-4.1.0]# locate libmysqlclient
/usr/lib/mysql/libmysqlclient_r.so.10.0.0
/usr/lib/mysql/libmysqlclient_r.so
/usr/lib/mysql/libmysqlclient.a
/usr/lib/mysql/libmysqlclient.so.10.0.0
/usr/lib/mysql/libmysqlclient.so.14
/usr/lib/mysql/libmysqlclient_r.so.14.0.0
/usr/lib/mysql/libmysqlclient.so.10
/usr/lib/mysql/libmysqlclient_r.so.14
/usr/lib/mysql/libmysqlclient.so.14.0.0
/usr/lib/mysql/libmysqlclient_r.a
/usr/lib/mysql/libmysqlclient.so
/usr/lib/mysql/libmysqlclient_r.so.10

Then you have to add:

Code:

---

-I /usr/include/mysql/ -L /usr/lib/mysql/

---

to configure options.

After configuring everything with the qt plugin as:

./configure -plugin-sql-mysql -I /usr/include/mysql/ -L /usr/lib/mysql/

Everything went fine, but according to the documentation I should then type:

make sub-plugins

But, I get this error:

[root@dhcp-57106 qt]# make sub-plugins
make: *** No rule to make target `sub-plugins'. Stop.
[root@dhcp-57106 qt]#

Try:

Code:

---

$ cd $QTDIR/src
$ make sub-plugins

---

I am using Fedora Core 4.

I would like to install Qt-4 and MySQL-4. I have downloaded and installed MySQL client and server with the libraries.

I am going to install Qt from source... so please tell me what are the steps to have it installed and working with MySQL ?

Quote:

---

Originally Posted by probine

I am using Fedora Core 4.

I would like to install Qt-4 and MySQL-4. I have downloaded and installed MySQL client and server with the libraries.

I am going to install Qt from source... so please tell me what are the steps to have it installed and working with MySQL ?

---

Please, don't start more than one thread on the same problem.

ok... fresh start

I am building Qt-4.1.x from source

I would like to install Qt-4.1.x and MySQL-4.x.

All MySQL is installed, what are the commands to install Qt-4.1.x with MySQL ?