qsqlquery UPDATE how to?

[Seishin]

The grammar looks right. Maybe you should try to add your database to the query declaration so the query knows which is the default database?

QSqlQuery query(db);

QSqlQuery query(db);

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[mardi]

Hi Unix777,

I make a sample using postgresql, hope this can help you

QString user = ui->lineEdit_user->text();
QString pass = ui->lineEdit_pass->text();
 
 
if (!db.isOpen())
   db.open();
 
QSqlQuery query(QString("UPDATE mnp_userlist SET (userlist_pass) = (\'%0\') WHERE userlist_user = \'%1\';").arg(pass).arg(user), db);
db.close();

QString user = ui->lineEdit_user->text();
QString pass = ui->lineEdit_pass->text();
    

if (!db.isOpen())
   db.open();

QSqlQuery query(QString("UPDATE mnp_userlist SET (userlist_pass) = (\'%0\') WHERE userlist_user = \'%1\';").arg(pass).arg(user), db);
db.close();

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Regards,
Mardi

[ChrisW67]

As Mardi's example shows,

query.prepare("UPDATE SET clients ClientName=:name, ClientCity=:city, ClientAddress=:address, ClientMol=:mol, ClientEik=:eik, ClientVat=:vat, ClientTel=:tel, ClientMail=:mail WHERE ROWID=:rowid");

query.prepare("UPDATE SET clients ClientName=:name, ClientCity=:city, ClientAddress=:address, ClientMol=:mol, ClientEik=:eik, ClientVat=:vat, ClientTel=:tel, ClientMail=:mail WHERE ROWID=:rowid");

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is not a valid SQL statement, it should read :

UPDATE clients SET ...

UPDATE clients SET ...

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Do NOT build SQL by pasting strings as Mardi suggests. Using bindValue() is, by far, the better and safer option.

[unix7777]

At first thank you to both of you!

I've changed the code to:

QSqlQuery query;
        query.prepare("UPDATE clients SET ClientName=:name, ClientCity=:city, ClientAddress=:address, ClientMol=:mol, ClientEik=:eik, ClientVat=:vat, ClientTel=:tel, ClientMail=:mail WHERE ROWID=:rowid");
        query.bindValue(":name", ui->lineEdit_name->text());
        query.bindValue(":city", ui->lineEdit_city->text());
        query.bindValue(":address", ui->lineEdit_address->text());
        query.bindValue(":mol", ui->lineEdit_mol->text());
        query.bindValue(":eik", ui->lineEdit_eik->text());
        query.bindValue(":vat", ui->lineEdit_vat->text());
        query.bindValue(":tel", ui->lineEdit_tel->text());
        query.bindValue(":mail", ui->lineEdit_mail->text());
        query.bindValue(":rowid", QString::number(rowid));
        query.exec();

QSqlQuery query;
        query.prepare("UPDATE clients SET ClientName=:name, ClientCity=:city, ClientAddress=:address, ClientMol=:mol, ClientEik=:eik, ClientVat=:vat, ClientTel=:tel, ClientMail=:mail WHERE ROWID=:rowid");
        query.bindValue(":name", ui->lineEdit_name->text());
        query.bindValue(":city", ui->lineEdit_city->text());
        query.bindValue(":address", ui->lineEdit_address->text());
        query.bindValue(":mol", ui->lineEdit_mol->text());
        query.bindValue(":eik", ui->lineEdit_eik->text());
        query.bindValue(":vat", ui->lineEdit_vat->text());
        query.bindValue(":tel", ui->lineEdit_tel->text());
        query.bindValue(":mail", ui->lineEdit_mail->text());
        query.bindValue(":rowid", QString::number(rowid));
        query.exec();

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But still nothing happens.The db is declared in main function and this is not the problem, because INSERT function works on same way!
Another suggestions?

[Lesiok]

Because the glass ball is now free :
1. Why are binding to :rowid text value not number ? What is a type of rowid column in database ?
2. What is a result of query.exec() (true or false).
3. If false what is a result of query.lastError().

[unix7777]

With this code i got "Success!" but nothing happens again!
In accordance with sqlite documentation ROWID should be a int.

QSqlQuery query;
        query.prepare("UPDATE clients SET ClientName=:name, ClientCity=:city, ClientAddress=:address, ClientMol=:mol, ClientEik=:eik, ClientVat=:vat, ClientTel=:tel, ClientMail=:mail WHERE ROWID=:rowid");
        query.bindValue(":name", ui->lineEdit_name->text());
        query.bindValue(":city", ui->lineEdit_city->text());
        query.bindValue(":address", ui->lineEdit_address->text());
        query.bindValue(":mol", ui->lineEdit_mol->text());
        query.bindValue(":eik", ui->lineEdit_eik->text());
        query.bindValue(":vat", ui->lineEdit_vat->text());
        query.bindValue(":tel", ui->lineEdit_tel->text());
        query.bindValue(":mail", ui->lineEdit_mail->text());
        query.bindValue(":rowid", rowid);
        if (query.exec())
        {
    emit updateTable();
    QMessageBox::information(this,"", "Success!");
        }
        else
        {
    QMessageBox::information(this,"", query.lastError().text());
 
        }
    this->close();

QSqlQuery query;
        query.prepare("UPDATE clients SET ClientName=:name, ClientCity=:city, ClientAddress=:address, ClientMol=:mol, ClientEik=:eik, ClientVat=:vat, ClientTel=:tel, ClientMail=:mail WHERE ROWID=:rowid");
        query.bindValue(":name", ui->lineEdit_name->text());
        query.bindValue(":city", ui->lineEdit_city->text());
        query.bindValue(":address", ui->lineEdit_address->text());
        query.bindValue(":mol", ui->lineEdit_mol->text());
        query.bindValue(":eik", ui->lineEdit_eik->text());
        query.bindValue(":vat", ui->lineEdit_vat->text());
        query.bindValue(":tel", ui->lineEdit_tel->text());
        query.bindValue(":mail", ui->lineEdit_mail->text());
        query.bindValue(":rowid", rowid);
        if (query.exec())
        {
    emit updateTable();
    QMessageBox::information(this,"", "Success!");
        }
        else
        {
    QMessageBox::information(this,"", query.lastError().text());

        }
    this->close();

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[Lesiok]

It just means that the SQL statement is correct formally. What is the value of the variable rowid ? There has to be a record in the table with the corresponding rowid ?

[unix7777]

The SQLite editor i use SQLiteStudio doesn't show ROWID. In the program row id is an int.But in another parts i use QString to insert it in the query.

[Lesiok]

Where did you get the value of rowid?

[unix7777]

there is a member function that set it.And i pass it after creating the object.The rowid int works i test it with QMessage, it display exactly what i select.

[ChrisW67]

If "nothing is happening" then either;

• the rowid is does not correspond to any row in the table, or
• the row already contained the data you were updating it to and therefore has no net change.

ROWID is an internal row identifier provided by Sqlite. It is a 64-bit integer allocated by Sqlite (not you). The only reasonable source for a rowid is from an existing row in the same Sqlite table.

[unix7777]

I have changed everything.In accordance with documentation here http://stackoverflow.com/questions/5...em-with-python
i add id int and i give NULL for every record.On this way it auto-increment every next record.What happens - everything work except the UPDATE statement.
It gives me: " Parameter count mismatch"!

QString row=QString::number(rowid);
    QSqlQuery query;
    query.prepare("UPDATE clients SET (ClientName, ClientCity, ClientAddress, ClientMol, ClientEik, ClientVat, ClientTel, ClientMail) WHERE id="+row+
            "VALUES (?, ?, ?, ?, ?, ?, ?, ?)");
    query.addBindValue(ui->lineEdit_name->text());
    query.addBindValue(ui->lineEdit_city->text());
    query.addBindValue(ui->lineEdit_address->text());
    query.addBindValue(ui->lineEdit_mol->text());
    query.addBindValue(ui->lineEdit_eik->text());
    query.addBindValue(ui->lineEdit_vat->text());
    query.addBindValue(ui->lineEdit_tel->text());
    query.addBindValue(ui->lineEdit_mail->text());
 
    this->close();
    if (query.exec())
    {
        emit updateTable();
    }
    else
    {
        QMessageBox::information(this,"", query.lastError().text());
    }
 
    this->close();

QString row=QString::number(rowid);
    QSqlQuery query;
    query.prepare("UPDATE clients SET (ClientName, ClientCity, ClientAddress, ClientMol, ClientEik, ClientVat, ClientTel, ClientMail) WHERE id="+row+
            "VALUES (?, ?, ?, ?, ?, ?, ?, ?)");
    query.addBindValue(ui->lineEdit_name->text());
    query.addBindValue(ui->lineEdit_city->text());
    query.addBindValue(ui->lineEdit_address->text());
    query.addBindValue(ui->lineEdit_mol->text());
    query.addBindValue(ui->lineEdit_eik->text());
    query.addBindValue(ui->lineEdit_vat->text());
    query.addBindValue(ui->lineEdit_tel->text());
    query.addBindValue(ui->lineEdit_mail->text());

    this->close();
    if (query.exec())
    {
        emit updateTable();
    }
    else
    {
        QMessageBox::information(this,"", query.lastError().text());
    }

    this->close();

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I would like to test it with some exact number of row, for example i want to update row 1 only to see whether it works.Unfortunately i don't know the syntax to do it.