Python：dbcur.execute AttributeError：'NoneType'對象沒有屬性'execute'

Question

我正在嘗試執行以下代碼：

def getServerSetting(self, setting):
    self.dbcur.execute('select value from settings where setting = ?', [str(setting)])
    rrf = self.dbr.fetchone()
    if rrf is None:
        return False
    else:
        return rrf[0]

但是，運行python腳本時出現此錯誤：

dbcur.execute('select value from settings where setting = ?', [str(setting)])
AttributeError: 'NoneType' object has no attribute 'execute'

Answer 1

嘗試這樣編寫函數。 如果仍然有錯誤，請告訴我。

def getServerSetting(self, setting):

    if not self.dbcon:
        self.dbcon = MySQLdb.connect(host='localhost', user='removed', passwd='removed', db='removed', port=21)
    self.dbcur = self.dbcon.cursor()

    self.dbcur.execute('select value from settings where setting = ?', [str(setting)])
    rrf = self.dbr.fetchone()
    if rrf is None:
            return False
    else:
            return rrf[0]