Question

经过多次尝试python3（在此语言中仍然是新的）， cursor.execute 这一行将阻止for循环在条件满足时继续。但是当我评论 cursor.execute 行时，循环能够继续直到结束。我怎样才能继续直到循环的最后结果？

目标实现： - 我正在尝试从CFC_xxxx表中过滤掉一堆数据，处理并将其放回SENSOR_TREEHUGGERS表中。

显示停止发生的行： -

cursor.execute（的SQLInsert，（xxGatewayId，qqqGatewayId，treeDiameter，温度，recordTime，DATETIME treeHuggerID））

Python3代码： -

import base64
import struct
import pymysql.cursors
import sys 
import datetime
from contextlib import closing

connection = pymysql.connect(host='localhost',
                user='xxx',
                password='xxx',
                db='xxx',
                charset='utf8mb4',
                cursorclass=pymysql.cursors.DictCursor)

with closing(connection.cursor()) as cursor:
 sql = "SELECT * FROM CFC_xxxx"
 cursor.execute(sql)
 for row in cursor:
  check = struct.unpack('>15x2f4B1L1x', base64.b64decode(row['Value']))

  if check[6] > 20000 or check[6] < 10000:
   continue
  else:
   xxGatewayId = int(row['Node_ID'])
   qqqGatewayId = int(row['Gateway_ID'])
   treeDiameter = int(check[0])
   temperature = int(check[1])
   recordTime = str(row['Timestamp'])
   year = datetime.datetime.fromtimestamp(row['Timestamp']).strftime('%Y')
   if check[2] == 0:
    hours = '00'
   else:
    hours = str(check[2])

   if check[3] == 0:
    minute = '00'
   else:
    minute = str(check[3])

   if check[4] < 10: 
    day = '0'+str(check[4])
   else:
    day = str(check[4])

   if check[5] < 10: 
    month = '0'+str(check[5])
   else:
    month = str(check[5])

   dateTime = str(year + '-' + month + '-' + day + ' ' + hours + ':' + minute + ':00')
   treeHuggerID = int(check[6])

   sqlInsert = "INSERT INTO SENSOR_TREEHUGGERS(`xx_Gateway_Id`,`qqq_Gateway_Id`,`treeDiameter`,`temperature`,`recordTime`,`dateTime`,`TreeHuggerId`) VALUES (%s,%s,%s,%s,%s,%s,%s)"
   cursor.execute(sqlInsert, (xxGatewayId,qqqGatewayId,treeDiameter,temperature,recordTime,dateTime,treeHuggerID))
   connection.commit()

Answer 1

以下是我如何解决问题。使用数组附加所有已处理的数据，并使用 executemany 立即保存。在事先，必须修改mysql配置 max_allowed_packet = 500M

痛苦但有价值的教训。

答案： -

import base64
import struct
import pymysql.cursors
import sys 
import datetime
from contextlib import closing

collectData = []
connection = pymysql.connect(host='localhost',
                user='xxx',
                password='xxx',
                db='xxx',
                charset='utf8mb4',
                cursorclass=pymysql.cursors.DictCursor)

with closing(connection.cursor()) as cursor:
 sql = "SELECT * FROM CFC_xxxx"
 cursor.execute(sql)
 for row in cursor:
  check = struct.unpack('>15x2f4B1L1x', base64.b64decode(row['Value']))

  if check[6] > 20000 or check[6] < 10000:
   continue
  else:
   xxGatewayId = int(row['Node_ID'])
   qqqGatewayId = int(row['Gateway_ID'])
   treeDiameter = int(check[0])
   temperature = int(check[1])
   recordTime = str(row['Timestamp'])
   year = datetime.datetime.fromtimestamp(row['Timestamp']).strftime('%Y')
   if check[2] == 0:
    hours = '00'
   else:
    hours = str(check[2])

   if check[3] == 0:
    minute = '00'
   else:
    minute = str(check[3])

   if check[4] < 10: 
    day = '0'+str(check[4])
   else:
    day = str(check[4])

   if check[5] < 10: 
    month = '0'+str(check[5])
   else:
    month = str(check[5])

   dateTime = str(year + '-' + month + '-' + day + ' ' + hours + ':' + minute + ':00')
   treeHuggerID = int(check[6])
   collectData.append(xxGatewayId,qqqGatewayId,treeDiameter,temperature,recordTime,dateTime,treeHuggerID)

  c1 = connection.cursor()
  sqlInsert = "INSERT INTO  SENSOR_TREEHUGGERS(`xx_Gateway_Id`,`qqq_Gateway_Id`,`treeDiameter`,`temperature`,`recordTime`,`dateTime`,`TreeHuggerId`) VALUES (%s,%s,%s,%s,%s,%s,%s)"
  c1.executemany(sqlInsert, collectData)
  connection.commit()

cursor.exe之后的Python3停了吗？

1 个答案: