QODBC

beecksche

@lina
Have a look here http://doc.qt.io/qt-5.6/sql-driver.html#qodbc-for-open-database-connectivity-odbc

As far as i know, in newer versions of Qt ( > 5.6.0) the ODBC driver is installed by default (https://bugreports.qt.io/browse/QTBUG-49420). So you can also download the newest version of Qt, if you do not want to build it by yourself.

michalos

Hi,
If You have Qt 5.6 You should have the ODBC driver.
I think that You should select the ODBC driver, when connecting to the DB.

Can You paste some code, to show how Your connection to the DB looks like?

lina

@michalos
Hi Michalos
this is my code:

QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
db.setDatabaseName(":memory:");
qDebug() << "db open" << db.open();

// create a table in the memory DB
QSqlQuery q_create = db.exec("CREATE TABLE qdn (id int, name varchar(50))");
qDebug() << "create: " << q_create.lastError();

// populate with some data
QSqlQuery q_insert(db);
q_insert.prepare("INSERT INTO qdn (id, name) VALUES (:id, :name)");
q_insert.bindValue(":id", QVariant::fromValue(1));
q_insert.bindValue(":name", "Volker");
qDebug() << "insert volker: " << q_insert.exec();

q_insert.bindValue(":id", QVariant::fromValue(2));
q_insert.bindValue(":name", "Root");
qDebug() << "insert root: " << q_insert.exec();

// create a new file based database and attach it
// to the existing Qt DB handle
QString sqlAttach = QString("ATTACH DATABASE '%1' AS fileDB")
.arg(QDir::toNativeSeparators("../sqlModel/qdn.db"));
QSqlQuery q_attach = db.exec(sqlAttach);
qDebug() << "attach: " << q_attach.lastError();

// create the table in the file based DB as a copy
// of the in memory DB
QSqlQuery q_create_fdb = db.exec("CREATE TABLE fileDB.qdn AS SELECT * from qdn");
qDebug() << "create select: " << q_create_fdb.lastError();

also this is ODBC driver pic on my computer :

also this is sqldrivers in QT installation folder:

Devopia53

@lina

Hi.

You can follow the suggestions of @mtrch and @beecksche .
Please upgrade to version 5.6.1 or higher or build the source.

lina

@Devopia53

Hi Devopia53

I coulden't find the path : Src\qtbase\src\plugins\sqldrivers\odbc on my computer. however I have the odcb driver in odcb data source administrator window. should I install qt source seprately? where can I download qt source for windows?

Devopia53

@lina

The file you need is plugin(aka qsqlodbc.dll), not ODBC driver.
You can download separately. Here

michalos

I'm no expert on ODBC, but I had to connect to a Netezza DB last week and all it took was to:

install the Netezza ODBC driver
configure the ODBC connection in windows (%windir%\system32\odbcad32.exe) and add the DNS user
followed the instruction on http://doc.qt.io/qt-5.7/sql-driver.html
a) Be aware that when connecting to an ODBC datasource you must pass in the name of the ODBC datasource to the QSqlDatabase::setDatabaseName() function rather than the actual database name.
b)With Microsoft SQL Server the result set returned by a stored procedure that uses the return statement, or returns multiple result sets, will be accessible only if you set the query's forward only mode to forward using QSqlQuery::setForwardOnly().

Unfortunetly I don't have the code right now.
I will try to post it in the next 12h.

lina

@Devopia53

I downloaded Qt Open Source 5.6. May this version haven't accurate proficiency requirements for using ODCB?

michalos

I have Qt 5.6.2 Open Source and I have the ODBC driver in ‪C:\Qt\5.6\mingw49_32\plugins\sqldrivers\qsqlodbc.dll

lina

@michalos

I don't have this .dll where can I download that? I would be grateful if you could send it for me.

Devopia53

@lina

Due to a simple mistake on the Qt side, it is missing from that version 5.6.0 and is not related to performance.

It is a simple matter to solve by following the method proposed by @mtrch .

lina

@Devopia53 said in QODBC:

on 5.6.0

thank you very much. I use the 5.6.0 version. I hit similar solutions everywhere and never find this path on my computer. I'll install a new version.

michalos

@lina
Or just use the qt maintenance tool and chose 'update' to 5.6.2

isan

@lina
You just need reinstall qt 5.6.0 and in select components step ,choose select all ,or choose Sources in subset of Qt5.6
after installation you have src folder in C:\Qt\Qt5.6.0\5.6 and you can find odbc folder in there

@Devopia53
It isn't missing from version 5.6.0

lina

@isan

yeah. I didn't install qt5.6.0 completely. I re-install it and it works now