Disconnecting from database after using QSqlTableModel

[RobbieClarken]

Hi,

I'm trying to create a GUI which has three buttons:

• connectButton: Connects to a SQLite3 database file on my computer.
• showTableButton: Shows a table from the database file in a QTableView.
• disconnectButton: Disconnects from the database file so I can edit it externally without closing the QT GUI.

The code for each button is:

on_connectButton_clicked():

QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", "metadataDB");
db.setDatabaseName("metadata.db");

QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", "metadataDB");
db.setDatabaseName("metadata.db");

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on_showTableButton_clicked():

QSqlDatabase db = QSqlDatabase::database("metadataDB");
QSqlTableModel *model = new QSqlTableModel(this,db);
model->setEditStrategy(QSqlTableModel::OnManualSubmit);
model->setTable("TableName");
model->select();
QTableView *view = new QTableView;
view->setModel(model);
view->show();

QSqlDatabase db = QSqlDatabase::database("metadataDB");
QSqlTableModel *model = new QSqlTableModel(this,db);
model->setEditStrategy(QSqlTableModel::OnManualSubmit);
model->setTable("TableName");
model->select();
QTableView *view = new QTableView;
view->setModel(model);
view->show();

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on_disconnectButton_clicked()

QSqlDatabase db = QSqlDatabase::database("metadataDB");
db.close();
QSqlDatabase::removeDatabase("metadataDB");

QSqlDatabase db = QSqlDatabase::database("metadataDB");
db.close();
QSqlDatabase::removeDatabase("metadataDB");

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The program connects to the database and displays the table correctly. However disconnectButton() doesn't release the metadata.db file. So if I try and delete or rename the file I get "the process cannot access the file because it is being used by another process". If I close the QT GUI then metadata.db is accessible again. Similarly if I never call showTableButton then metadata.db is always accessible.

If anyone could point out what I'm doing wrong I would greatly appreciate it. I suspect I need to delete the QTableModel but I'm not sure how to get a handle for it from inside disconnectButton().

Regards,

Robbie

[spirit]

did you try to do something like this?

QSqlDatabase db = QSqlDatabase::database("metadataDB");
db.close();
QSqlDatabase::removeDatabase("metadataDB");
db = QSqlDatabase();

QSqlDatabase db = QSqlDatabase::database("metadataDB");
db.close();
QSqlDatabase::removeDatabase("metadataDB");
db = QSqlDatabase();

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[RobbieClarken]

did you try to do something like this?

QSqlDatabase db = QSqlDatabase::database("metadataDB");
db.close();
QSqlDatabase::removeDatabase("metadataDB");
db = QSqlDatabase();

QSqlDatabase db = QSqlDatabase::database("metadataDB");
db.close();
QSqlDatabase::removeDatabase("metadataDB");
db = QSqlDatabase();

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Hi spirit,

Thanks for the suggestion. Alas that doesn't work. Neither does redefining db.setDatabaseName(). I do suspect it will be something simple like that!

[mazurekwrc]

I don't look to your file only to this code on page, have you use somewhere

db.open()

db.open()

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[RobbieClarken]

I don't look to your file only to this code on page, have you use somewhere

db.open()

db.open()

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You're right that I did forget that line. Unfortunately inserting it doesn't resolve my problem.

[spirit]

You're right that I did forget that line. Unfortunately inserting it doesn't resolve my problem.

that's not an error, because you use QSqlDatabase::database and this method automatically opens database, from docs.

QSqlDatabase QSqlDatabase::database ( const QString & connectionName = QLatin1String( defaultConnection ), bool open = true ) [static]

[mazurekwrc]

maybe try in on_disconnectButton_clicked first delete model and after that close and remove database