Filtering QSqlTableView data
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Hi all,
I am working on a project which include data presentation from the database. I have created an QSqlRelationalTableModel model and I have added that model to QSqlTableView. This part works OK. I have loaded data into model using some constraints, for example I am showing only students that are enrolled in specific course.
I have created an QLineEdit which accepts in this example student names and filters this view in this way:
localStudentModel->setFilter(QString("fName LIKE '%1%'").arg(ui.lineEditFName->text()));I have connected this QLineEdit via signal and slot mechanism and each time I type a letter into line edit model is filtered using above statement. Problem occurs when I delete all the letters that I have entered into this lineedit.
In order to remove a filter I use this statement:
localGradesModel->setFilter("");When this statement executes I not only get students from specific course, but all the students that are stored in the students table, which of course is not something that I want.
Is there a better way to filter already presented data in QTableView?
Tnx,
Zgembo -
Hi,
For this use case, you could add a QSortFilterProxyModel.
So you can filter the loaded data without touching the SQL filters.
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@SGaist said in Filtering QSqlTableView data:
Hi,
For this use case, you could add a QSortFilterProxyModel.
So you can filter the loaded data without touching the SQL filters.
Thank you for your suggestion. It works like a charm :-)
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I have managed to present students data using QSortFilterProxyModel, but I am having some problems with it.
When I open a page that lists all the students I call part of the code:localStudentModel = hStudents->getStudents(); proxyModelStudents->setSourceModel(localStudentModel); proxyModelStudents->setDynamicSortFilter(true); ui.tableViewStudents->setModel(proxyModelStudents);
localStudentModel is QSqlRelationalTableModel pointer. Everything works the first time that I open this screen. It is stacked widget type of the screen so I need to move between screen for other purposes.
If I click on the students button again I need to reload students table because there is a possibility that I have inserted new rows into students table so I call the same part of the code again.
This time application crashes with debug assertion failure.ASSERT: "source_to_proxy.size() > end" in file itemmodels\qsortfilterproxymodel.cpp, line 1282
Debug Error!I am not sure what might be a problem.
Tnx
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What is that localStudentModel ?
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You are creating a completely new model each time ?
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Ok, so what exactly happens when you click on that "students button" ?
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Well I open specific stack widget page, query "student" table and return all data to localStudentModel. Then I setup proxymodelStudents whit that model and assign that proxyModelStudent to QTableView that is located on that stackwidget page.
After that I just hide some columns and organize that qtableview. This all works first time I open the page.
Second time I click on students button program crashes with this message:And one more thing. Before I added proxyModel this all worked.
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But why not just refresh the model query ? From your description it looks like you are re-creating the whole stuff each time you click on that button.
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Just update the query of your model.