QtSQL - Where is My Database?

[feuerball11]

Hello There.

I Have an Database from 1Blue, with the table "test"

now i Can connect without problems, but db.tables() says that there are no tables. Why?

My Code (Zensored)

QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
db.setHostName("mysql12.1blu.de");
db.setDatabaseName("***********");
db.setUserName("**********");
db.setPassword("**********");
bool ok = db.open();
qDebug() << db.tables();
qDebug() << db.isValid();
qDebug() << db.isOpen();

QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
db.setHostName("mysql12.1blu.de");
db.setDatabaseName("***********");
db.setUserName("**********");
db.setPassword("**********");
bool ok = db.open();
qDebug() << db.tables();
qDebug() << db.isValid();
qDebug() << db.isOpen();

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And the Return:
()
true
true

So why there are no tables? In phpMyAdmin there are tables!

I hope someone can help me.

MFG feuerball11

PS: Sorry for bad english

[wysota]

You're using a wrong driver. If you want to connect to a MySQL database, use QMYSQL driver instead of QSQLITE.

[feuerball11]

Then its not Working. The Programm returns:

QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QODBC3 QODBC QPSQL7 QPSQL
()
false
false

[wysota]

Then you need to install the driver or its dependencies.

[feuerball11]

Sry for the noob question, but where can i get this driver? must everone install this driver how uses my programm, or only i to compile it?

[wysota]

Check if you have the plugin library available. If yes, then probably all you need is to install MySQL client libraries. If no, you'll need to build the plugin

[ChrisW67]

If you are using the Qt SDK then you might find this [WIKI]Building the Database Plugins for QtSDK Users[/WIKI] wiki page useful in conjunction with the docs that wysota linked to.

You will not need to compile the plugin for every user but you will need to deploy the plugin and the MySQL client libraries with your software.

[feuerball11]

AT first. I Using Visual Studio 2008

I compiled the plugin again and again. but its not working.

i put qsqlmysqld4.dll and qsqlmysqld4.lib into the folder
C:\Qt\4.8.2\plugins\sqldrivers

but qt says only:

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

can anyone helb me? it cant be so difficult to run this plugin -.-

[ChrisW67]

You do not have to manually copy anything to install the plugin:

nmake install

nmake install

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does that for you.

The MySQL runtime libraries must be available in the environment (i.e. PATH) of the running program in order to load the plugin.

[feuerball11]

nmake install was sucsesfull, but it doesent work again...

"Testumgebung.exe": "C:\Qt\4.8.2\plugins\sqldrivers\qsqlmysqld4.dl l" geladen, Symbole wurden geladen.
"Testumgebung.exe": "C:\Qt\4.8.2\plugins\sqldrivers\qsqlmysqld4.dl l" entladen.
QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QODBC3 QODBC QPSQL7 QPSQL

.... this is anoying ...

[ChrisW67]

The MySQL runtime libraries must be available in the environment (i.e. PATH) of the running program in order to load the plugin.

It might be annoying, but you already have the answer. Just like any other piece of code, the Qt MySQL plugin cannot load if it cannot find the libraries it depends on. These libraries are part of MySQL and nothing to do with Qt itself. Windows has a well documented search mechanism for locating dynamically loaded libraries.

On your development machine you can simply place the MySQL bin directory into the system PATH or the PATH used by your IDE to run the software. (Just like the PostgreSQL libraries must be).

[Viper666]

nmake install was sucsesfull, but it doesent work again...

"Testumgebung.exe": "C:\Qt\4.8.2\plugins\sqldrivers\qsqlmysqld4.dl l" geladen, Symbole wurden geladen.
"Testumgebung.exe": "C:\Qt\4.8.2\plugins\sqldrivers\qsqlmysqld4.dl l" entladen.
QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QODBC3 QODBC QPSQL7 QPSQL

.... this is anoying ...

Sorry i don't read full thread but why are you not use QODBC driver? i use it with MySql and it work fine