Python脚本返回旧的MySQL值（直到重新启动）

Question

我有下面的代码，我运行一次，然后再次插入一个新的值来刷新。

def getStageAdditives(self, stage): 
     stagesAdditivesSelectQuery = """SELECT  a.id, 
                a.name, 
                IFNULL(sa.dose, 0) as dose, 
                IFNULL(sa.last_dose, 0) as last 
             FROM  additives a 
             LEFT JOIN stage_additives sa 
             ON   a.id = sa.additive_id 
             AND   sa.stage_id = (
             SELECT  id 
             FROM  stages 
             WHERE  name = '""" + stage + """') 
             ORDER BY a.name""" 

     self.cursor.execute(stagesAdditivesSelectQuery) 
     data = self.cursor.fetchall() 

     additives = [] 
     for additive in data: 
      id = additive[0] 
      name = additive[1] 
      dose = additive[2] 
      last = additive[3] 
      additives.append({ 'title': name, 'dose': dose, 'last': last }) 
     print stagesAdditivesSelectQuery 
     return additives 

的问题是，当我使用下面的代码中插入一个值“添加剂”表我老值（新值缺失）。

def createAdditive(self, name): 
     additiveInsertQuery = """ INSERT INTO additives 
            SET   name = '""" + name + """'""" 
     try: 
      self.cursor.execute(additiveInsertQuery) 
      self.db.commit() 
      return "True" 
     except: 
      self.db.rollback() 
      return "False" 

我可以通过查看phpMyAdmin来确认数值正在插入到数据库中。如果我重新启动脚本，我会按预期得到新值。如果我用phpMyAdmin运行查询也返回新值。刷新页面并等待10秒以上并没有帮助，我仍旧得到旧值。

如果它很重要，两种方法都在单独的类/文件中。在'createAdditive'方法成功返回后，使用ajax调用getStageAdditives。

DB初始化：

import MySQLdb 
import time 

class Stage: 
    def __init__(self): 
     self.db = MySQLdb.connect('192.168.0.100', 'user', 'pass', 'dbname') 
     self.cursor = self.db.cursor() 

检索类似的值获得新的值如预期（同一类createAdditives）的另一种方法：

def getAdditives(self, additive=None): 
     where = '' 
     if additive is not None: 
      where = "WHERE pa.additive_id = (" 
      where += "SELECT id FROM additives " 
      where += "WHERE name = '" + additive + "') " 
      where += "AND a.name = '" + additive + "'" 

     additiveSelectQuery = """ SELECT  a.name, 
               pa.pump_id 
            FROM  additives a, 
               pump_additives pa """ + where + """ 
            ORDER BY a.name""" 

     self.cursor.execute(additiveSelectQuery) 
     data = self.cursor.fetchall() 

     additives = [] 
     for item in data: 
      additives.append({'additive': item[0], 'pump': item[1]}) 
     return additives 

Answer 1

对于那些谁发现了这个问题：类似的问题是：解决在Why are some mysql connections selecting old data the mysql database after a delete + insert?

诀窍是添加一个connection.commit（）。