pyqt5-没有查询无法获取行

Question

我使用QSQLQUERY加入两个SQLITE表的问题。运行程序时，我会收到错误“无查询无法获取行”。我找不到哪个问题是 在sqlitestudio中执行相同的查询，它可以正常工作。 在下面，我将代码，表结构和.UI文件放置。 感谢您的任何帮助

import sys
from PyQt5 import QtWidgets, QtCore, QtGui
from PyQt5.QtCore import QSize, Qt, QModelIndex
from PyQt5.QtSql import QSqlDatabase, QSqlTableModel, QSqlRelation, QSqlQuery, QSqlQueryModel
from PyQt5.QtWidgets import QApplication, QTableView,QWidget
from quadro_costiUi import Ui_f_riepilogoCosti

class QuadroCosti(QWidget, Ui_f_riepilogoCosti):
    def __init__(self):
        super().__init__()
        
        con=QSqlDatabase.addDatabase('QSQLITE')
        con.setConnectOptions("detect_types=sqlite3.PARSE_DECLTYPES | sqlite3.PARSE_COLNAMES")
        con.setDatabaseName("/Users/User/Documents/Micro/db/Micro.db")
        con.open()

        query=QSqlQuery()
        query.prepare("SELECT * FROM tb_PreventivoDatiGenerali \
                           INNER JOIN tb_PreventivoDettaglioFasi \
                           ON tb_PreventivoDettaglioFasi = tb_PreventivoDatiGenerali.codicePreventivo \
                           AND tb_PreventivoDettaglioFasi.revisionePreventivo = tb_PreventivoDatiGenerali.revisione")
        query.exec()
        print(query.lastError().text())                   

app = QApplication(sys.argv)
window = QuadroCosti()
window.show()
sys.exit(app.exec_())

- sqlite表格 -

CREATE TABLE tb_PreventivoDatiGenerali (
codicePreventivo INTEGER NOT NULL,
revisione VARCHAR NOT NULL,
nomePreventivo CHAR NOT NULL,
dataPreventivo DATETIME NOT NULL,
flagFasi BOOLEAN NOT NULL,
flagMateriale BOOLEAN NOT NULL,
dataInserimento VARCHAR,
dataModifica VARCHAR,
PRIMARY KEY (
codicePreventivo,
revisione
)
);

CREATE TABLE tb_PreventivoDettaglioFasi (
codicePreventivo INTEGER NOT NULL,
revisionePreventivo VARCHAR,
nomeFase CHAR (255),
internaEsterna CHAR (1),
quantità INTEGER,
PzPerCarico INTEGER,
Campioni INTEGER,
Risorsa STRING (5),
nrCarichi INTEGER,
barraUtile INTEGER,
setupOre REAL,
setupMinuti REAL,
cicloSecondi REAL,
cicloMinuti REAL,
[%scarto] REAL,
[%efficienza] REAL,
[€/h] REAL,
costoPerCarico REAL,
costoCadauno REAL,
costoAggiuntivo REAL,
[%ricarico] REAL,
[€/cadauno] REAL,
[T (h)] REAL,
[LT (gg)] REAL,
desMat CHAR,
quantitàMat INTEGER,
diametroMat REAL,
psMat REAL,
lungPezzoGrezzoMat INTEGER,
[€/KgMat] REAL,
[€/cadaunoMat] REAL,
[LTMat(gg)] REAL,
dataIns VARCHAR,
dataMod VARCHAR,
PRIMARY KEY (
codicePreventivo ASC,
revisionePreventivo,
nomeFase
)
);