@Kent-Dorfman said in calling stored procedure with prepared query vs execute:

Since a stored procedure is simply a server-side wrapper around an SQL transaction, it is IRRELEVANT AND REDUNDANT to wrap it in a prepared statement on the client.

Yes, I start to understand what you mean.
I will study in deep this argument.

Thanks a lot for your precious comments.

@SGaist

My bad ! I did not think to check the docs on that point !

A big thanks
Gérard

I tested a similar query (slightly modified tst_qsqlquery autotest) and it works fine for me:

QVERIFY( q.prepare( "select * from " + qtest_prepare + " where id = :id order by id LIMIT :limit FOR UPDATE" ) ); q.bindValue( ":id", i ); q.bindValue( ":limit", 1 ); QVERIFY_SQL( q, exec() ); QVERIFY_SQL( q, next() );

q.next() returns false if I pass 0 for :limit in bindValue().
Postgres 11 with Qt 5.13/dev

@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,

There’s also no need to allocate the query on the heap as the QSqlQueryModel::setQuery method parameter suggests.

As it is now, double is used.

Depending on how your DECIMAL filed is configured, it might be enough. If not, then you can modify the plugin to read the field as described here.

@jsulm said in Cannot retrieve the SQL query string from QSqlQuery?:

@mostefa This is not the answer to the question as @JNBarchan want to have the query text not its result.
From your example he wants to get "SELECT id,name,birthday FROM artist".

@mostefa As @jsulm says, I am indeed not looking to execute the query, rather only to retrieve its text.
This has indeed turned out to be QSqlQuery::lastQuery(), and I have now marked this question as Solved. Thanks all.

hi,

@LuAria ,

wat ws the value coming in Numtwo ?.
Nways ur got solution.
Happy coding.

Thanks,

Hi,

Did you check that you are using similar connection parameters for both your Dephi and C++ application ?

Может query.next() возвращает false ?

@SGaist
is VS express not excotic enough ? ;)

Can you show how you setup and run your query ?

@Kofr
If the above snippet works, then you don't respect the SQL's type. You're trying to pass a string representation to Qt when it clearly expects a binary (BLOB is "Binary Large OBject"). So then the question:

How to fix Qt implementation?

comes back as: "How to fix your implementation".
Anyway, I'd suggest passing the appropriate type to the driver. My thoughts are that something like this should be working:

const char rawData[4] = { 0x00, 0x00, 0x00, 0x07 }; QByteArray id = QByteArray::fromRawData(rawData, 4); QSqlQuery query; if (!query.prepare(QStringLiteral("SELECT row FROM %1 WHERE id = :id").arg(tableName))) // Handle the error! query.bindValue(":id", id); // Pass binary data for columns that expect binary if (!query.exec()) // Handle error again!

@Cleiton-Bueno Yes. If the query string is correct it will work.

@_compiler

Ok, i see, its a helper class.

Well you need to open a db then.

You dont need to do it in QueryBuilder.

If you open a db in main , QSqlQuery
will use this DB. You dont need pointer or reference.
Its handled internally.

@panosk

and to be honest I had already started work on this

You already have that in QSqlDatabase, you only need to keep track of the connections' names.

Good luck!

dont know. should work as before. just not inserting twice.

@alex_malyu Thanks a lot

The plugin hasn't changed anything related to that between 5.5 and 5.6 so I wonder if it's a change in QVariant.

By the way, why do you need that information ? You should be able to just convert to int without any problem.

Hi,

Sounds like a job for a query builder. Each time you modify one of these variable, you rebuild the query using condition based on what you need. i.e.:

QString query = "SELECT * FROM "; if (condition) { query += "WHERE foo=\"" + parameterValue + "\""; //etc. }

Hope it helps

Done :)

Adapted from the documentation example: model->setFilter("should_alarm=1");

At the end it was a typo. I was trying to insert a value into a column called Localización by using:

guardar_s.prepare("INSERT INTO Solicitudes_Trabajo (Localizacion)

The problem is in the accent mark.

So if anyone gets this error, watch out the typos.

Thanks @clochydd !

Solved.
I tried a lot of things to solve the problem. Some of them included calling next before accessing the result as @SGaist said, but it continued saying:

QSqlQuery::value: not positioned on a valid record

At last I created a new project with a new database and it worked properly with this code:

hospital=QSqlDatabase::addDatabase("QSQLITE"); hospital.setDatabaseName("C:/Sqlite3/Hospital.sqlite"); if(hospital.open()){ qDebug()<<"4.Se ha conectado a la base de datos Hospital"; }else{ qDebug()<<"4.ERROR. No se ha conectado a la base de datos Hospital"; } QSqlQuery mostrar; mostrar.prepare("SELECT*FROM Partes WHERE N_Parte=:ID"); mostrar.bindValue(":ID",ui->lineEditN_Parte->text()); if(mostrar.exec()) { qDebug()<<"5.Los datos del parte se han mostrado correctamente"; }else{ qDebug()<<"5.ERROR. Los datos del parte no se han mostrado correctamente"; qDebug()<<"5.ERROR:"<<mostrar.lastError(); } mostrar.next(); ui->tableWidget->setRowCount(15); QStringList Campos; Campos<<"Fecha de Emisión"<<"Unidad Hospitalaria"; ui->tableWidget->setVerticalHeaderLabels(Campos); ui->tableWidget->insertColumn(0); ui->tableWidget->setColumnCount(1); ui->tableWidget->setItem(0, 0, new QTableWidgetItem(mostrar.value(1).toByteArray().constData())); ui->tableWidget->setItem(2, 0, new QTableWidgetItem(mostrar.value(2).toByteArray().constData()));

So I guess the problem was in the database, maybe in the columns, maybe in the rows, maybe in the values or maybe in the name of each of them.

The important thing is that the code I post in this reply works perfectly, so if anyone has a similar problem I hope it helps.

Thank you very much!

Resuelto.
Intenté muchas cosas para solucionar el problem, algunas incluian la utilización de next() que me faltaba en el código de mi respuesta anterior pero continuaba saliendo el error:

QSqlQuery::value: not positioned on a valid record

Al final creé un nuevo proyecto con una base de atos nuevas y funciona correctamente con este código:

hospital=QSqlDatabase::addDatabase("QSQLITE"); hospital.setDatabaseName("C:/Sqlite3/Hospital.sqlite"); if(hospital.open()){ qDebug()<<"4.Se ha conectado a la base de datos Hospital"; }else{ qDebug()<<"4.ERROR. No se ha conectado a la base de datos Hospital"; } QSqlQuery mostrar; mostrar.prepare("SELECT*FROM Partes WHERE N_Parte=:ID"); mostrar.bindValue(":ID",ui->lineEditN_Parte->text()); if(mostrar.exec()) { qDebug()<<"5.Los datos del parte se han mostrado correctamente"; }else{ qDebug()<<"5.ERROR. Los datos del parte no se han mostrado correctamente"; qDebug()<<"5.ERROR:"<<mostrar.lastError(); } mostrar.next(); ui->tableWidget->setRowCount(15); QStringList Campos; Campos<<"Fecha de Emisión"<<"Unidad Hospitalaria"; ui->tableWidget->setVerticalHeaderLabels(Campos); ui->tableWidget->insertColumn(0); ui->tableWidget->setColumnCount(1); ui->tableWidget->setItem(0, 0, new QTableWidgetItem(mostrar.value(1).toByteArray().constData())); ui->tableWidget->setItem(2, 0, new QTableWidgetItem(mostrar.value(2).toByteArray().constData()));

Así que supongo que el problema estaba en la base de datos anterior, quizás en las columnas, quizás en las filas, quizás en los valores o quizás en el nombre de cada uno de estos elementos.
Lo importante es que el código que adjunto en esta respuesta funciona correctamente, de modo que si alguien tiene un problema parecido espero que esto le ayude.

Muchas gracias!

Thanks for sharing your solution !

Since you have it working now, please update the thread title prepending [solved] so other forum users may know a solution has been found :)

@p3c0 Thank you for your help

I have realized that

If query execution is a failure, than lastQuery() returns a string with either placeHolders or placeHolders replaced with quos. Making the user thinking something with binding is wrong. If query is succesful, lastQuery() returns either placeHolders replaced with quos or actual values.

I am going to further test things out and see if something may be improved with bindValue() and make a request based on that.

at funtion gerarRelatorio i swap the qDeleteAll on line down(original position). and it worked.

qDebug()<<"Documentos processados para a Tabela de Relatorio"; acessodb::setDataUltimoRelatorio(idEmpresa,idCliente); qDeleteAll(listaDocumentos); listaDocumentos.clear(); delete modelo; return true;

I now will upload to my test server, and see what happens.
i doesn't care any more about what is causing the problem, i just hope that is solved.

Thanks for the heads up. I had no idea.

Since I tried to use a model and failed, I became curious. I have done one more example using this tutorial, and it went fine. Do you have any idea why is it complaining about my database not being open, when it clearly is, judging from the fact that my query worked fine.

Indeed, as you wrote, you have 40GB database and I don't know the size of the images you have in there. So depending on that and the current number of entries you might be just filling your memory. Try starting with e.g. 100, if it resist increase the value.