qt - QTreeView very slow sorting -

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sorting qtreeview qsortfilterproxymodel extremely slow (compared basic qtreewidget). what's wrong code? how can speed-up?

# coding: utf-8  import sys pyqt5.qtwidgets import (qtreeview, qabstractitemview,                              qmainwindow, qapplication) pyqt5.qtsql import (qsqldatabase, qsqlquery, qsqlquerymodel) pyqt5.qtcore import qsortfilterproxymodel   class database:     def __init__(self):         self.db = qsqldatabase.adddatabase("qodbc")         self.db.setdatabasename(             r'driver={sql server native client 11.0};server={(localdb)\v11.0};')         self.db.open()   class model(qsqlquerymodel):     def __init__(self, parent=none):         super().__init__(parent)          query = qsqlquery()         query.prepare('select * companies name ?')         query.bindvalue(0, '%elektro%')         query.exec_()         self.setquery(query)   class treeview(qtreeview):         def edit(self, index, trigger, event):         if trigger == qabstractitemview.doubleclicked:             return false         return qtreeview.edit(self, index, trigger, event)   class window(qmainwindow):     def __init__(self):         super().__init__()          self.db = database()         self.model = model()         sortfiltermodel = qsortfilterproxymodel()         sortfiltermodel.setsourcemodel(self.model)          treeview = treeview(self)         treeview.setmodel(sortfiltermodel)         treeview.hidecolumn(0)         treeview.hidecolumn(9)         treeview.setindentation(0)         treeview.setselectionmode(qabstractitemview.multiselection)         treeview.setallcolumnsshowfocus(true)         treeview.setsortingenabled(true)         treeview.clicked.connect(self.row_id)          self.setcentralwidget(treeview)      def row_id(self, index):         if index.isvalid():             id_ = index.sibling(index.row(), 0).data()         print(id_)   if __name__ == '__main__':      app = qapplication(sys.argv)     window = window()     window.show()     app.exec_()

some tips (from c++ perspective, missing )

  1. qtreeview known being slower qtableview , consume lot of memory , using plain table model anyways, so, try qtableview.

    also, in real tree hierarchical model hiding column 0 hide child items.

  2. try using qsqltablemodel instead of qsqlquerymodel, has convenience setsort, setfilter methods , fetchs visible rows. faster.


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