Solution of https://stackoverflow.com/questions/46410120/changing-row-color-on-click-pyqt

main.py

import sys
from PyQt5 import QtCore, QtSql, QtWidgets, QtGui

class SqlTableModel(QtSql.QSqlTableModel):
    ExecuteRole = QtCore.Qt.UserRole + 1

    def __init__(self, parent=None, db = QtSql.QSqlDatabase()):
        QtSql.QSqlTableModel.__init__(self, parent, db)
        self.d = {}

    def data(self, index, role):
        if role == self.ExecuteRole:
            _id = self.getId(index)
            if _id in self.d.keys():
                return self.d[_id]
            return False

        if role == QtCore.Qt.BackgroundRole:
            if self.data(index, self.ExecuteRole):
                return QtGui.QBrush(QtCore.Qt.red)
            if 'MILESTONE' in QtSql.QSqlTableModel.data(self, self.index(index.row(), 2), QtCore.Qt.DisplayRole):
                return QtGui.QBrush(QtCore.Qt.yellow)

        return QtSql.QSqlTableModel.data(self, index, role)

    def getId(self, index):
        ix = self.fieldIndex("id")
        return self.data(self.index(index.row(), ix), QtCore.Qt.DisplayRole)

    def setData(self, index, value, role):
        if role == self.ExecuteRole:
            self.d[self.getId(index)] = value
            return True
        return QtSql.QSqlTableModel.setData(self, index, value, role)

    def roleNames(self):
        rn = QtSql.QSqlTableModel.roleNames(self)
        rn[self.SelectRole] = QtCore.QByteArray(b'execute')
        return rn


class TableView(QtWidgets.QTableView):
    def contextMenuEvent(self, event):
        pos = event.pos()
        menu = QtWidgets.QMenu()
        stepx = menu.addAction('Mark Step as Executed')
        stepdx = menu.addAction('Clear Step Execution')

        action = menu.exec_(self.mapToGlobal(pos))
        if action == stepx:
            if self.model():
                index = self.model().index(self.rowAt(pos.y()), 2)
                self.model().setData(index, True, SqlTableModel.ExecuteRole)
                row = index.row()
                self.model().dataChanged.emit(self.model().index(row, 0),
                                              self.model().index(row, self.model().columnCount()-1),
                                              [QtCore.Qt.BackgroundRole])


def createConnection():
    db = QtSql.QSqlDatabase.addDatabase('QSQLITE')
    db.setDatabaseName('memory')
    if not db.open():
        print("Cannot open database")
        return False

    query = QtSql.QSqlQuery()
    query.exec_("create table person(id int primary key, "
                "firstname varchar(20), lastname varchar(20),"
                "archive BOOLEAN NOT NULL CHECK (archive IN (0,1)))")

    query.exec_("insert into person values(101, 'Danny', 'MILESTONE', 1)")
    query.exec_("insert into person values(102, 'Christine', 'Holand', 0)")
    query.exec_("insert into person values(103, 'Lars', 'Gordon', 1)")
    query.exec_("insert into person values(104, 'Roberto', 'MILESTONE', 0)")
    query.exec_("insert into person values(105, 'Maria', 'MILESTONE', 1)")
    query.exec_("insert into person values(106, 'Luisa', 'Papadopoulos', 1)")
    query.exec_("insert into person values(107, 'Luis', 'Papadopoulos', 1)")

    return True


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)

    if not createConnection():
        sys.exit(1)
    w = TableView()
    model = SqlTableModel()
    model.setTable("person")
    model.select()
    w.setModel(model)
    w.show()
    sys.exit(app.exec_())