@JonB I do not understand anything. Please could you give more informantion.

Note : app release folder has
a476d8a3-0275-4b95-be08-69e8e7ca83ca-image.png

I solved the problem :)

I add lib files from Postgresql to release folder
341075a5-d9d5-4598-9bb3-6bbae3cee52c-image.png

and it works. thank you @jsulm and @JonB

@Narutoblaze
Then no you cannot, as you can see in the documentation for QTcpSocket/ QAbstractSocket. If there were a method which took a "connection name" you would see it documented.

There is nothing to stop you writing your own code to store connections indexed by some "connection name" you choose, e.g. using a QMap Class.

Hi and welcome to devnet,

There's no prebuilt MySQL for Androïd. If you really want that you'll have to first build the MariaDB client library for Androïd and then the MariaDB driver.

That said, when people try to access a MySQL database directly like that from Androïd, it means they are planning to expose their server directly on internet which is a very bad idea. The recommendation is to have a REST api in front of the database that will return only required data and also abstract the database itself.

I have worked with the qsqlcipher plugins well and gone through with the qsqlcipher plugin code and I puted some print statement in the plugin code itself then observed that the fetchNext function taking is more time, Please look into it

Thanks for your information.

It seems it's a bug, we can't use QT login Oracle as sysdba.

@JonB
sorry for that,

insert into Dataset(AT) values(?): I know nothing about SQLite. Dataset(AT) is a (syntactically valid) table to insert into, is it?
Yes, it is valid statement in sqlite.

Also QSqlQuery::prepare() returns a bool for success/failure, which you should be checking.
Returns true if the query is prepared successfully; otherwise returns false.

Plus, you check QSqlDatabase::lastError() after QSqlQuery::exec() fails, but that says
yes, I got error. like QSqlError("","","");

I checked again there was a problem in database but it solved thanks alot.
Now, I'm able to insert data into database from QXlsx file.

@Persivan said in QMYSQL driver not found after release:

Any ideas?

Yes, use search function in this forum - this is asked so often.
Most probably the MySQL driver lib is missing.

@artwaw

Thanks a lot ! It works.

I don't know how I could miss this one. It seems that every time I restart the server, the IP changes. I will have to set a fixed IP adress.

I got it fixed, thanks to @Christian-Ehrlicher!

I almost did not try your suggestion because I thought I knew very well where the warning comes from.

But it turned out that I had missed a setQuery() call that was lacking its second parameter (the database connection to use).

I have usually seen processEvent called from the main thread directly which forces processing of events however calling it from a different thread is the first time. As you can see there's some strange interaction. I currently wonder whether you have an event that is processed by the wrong event loop.

Upgrading to Qt Version 5.15+ solved the issue.

@Babs Anytime.
Please don't forget to mark the thread as "solved".

Process still block, when I lost connection.

@Alain38-0 said in QSqlDatabase and upgrade to Qt5.12:

Unfortunately with Qt5.12 nothing works. Because the database must be now in the same thread that the process using it.

I'm surprised it used to work at all. So far as I understood, it was always the case that database access had to be in same thread as where database created.

From the looks of it, you have to re-create the models when you change these settings.

@SGaist I did it this way for reading return params:

Query.nextResult(); // after reading table values //Get Return Parameter for (int i=0; i<CountReturnParam; i++) { qDebug() << QString("Returnparam %1 = %2") .arg(i).arg(Query.boundValue(i).toString()); }

Hi,

What version of Qt are you using ?

You should print the error you get if exec fails. That will give you clues as to what is happening.

On a side note, QString already provides easy to use arguments handling so you don't have to use snprintf.

@jsulm Thanks a lot!
Sorry for my miss on the link.
I will try it.

@koahnig
Well the "MySQL server has gone away" msg also seems slightly "wooden" so it fits perfectly :)